“The size of this project is remarkable — the viaduct is one of the largest in the world,” says Olivier Tricoire, Nouvelle Route du Littoral deputy director of operations. The ‘Nouvelle Route du Littoral’ is currently under construction in Réunion Island’s — a French department — Indian Ocean and is set to be one of the biggest projects ever undertaken by the French government. The 12.5km highway, parallel to the coast, will connect Saint Dennis with La Grande Chaloupe and replace the existing coastal road between Saint Dennis and La Possession. The existing road is exposed to sea spray when there’s heavy swell — frequently occurring due to the absence of a continental plateau — and to the falling of rocks. The 80,000 people who frequently use the road are often stuck in traffic jams, as the authorities have to close one or two lanes for a period of two months to a year. The new coastal highway will eliminate these issues, as it will be 20-30m above sea level — expected to be above the highest waves of the biggest storms. The €1.7bn development has been awarded to two joint ventures. The construction of the 5.4km viaduct section — €715M of works — is under the responsibility of the viaduct joint venture, which comprises Vinci Construction Grands Projects, Dodin Campenon Bernard, Bouygues Travaux Publics and Demathieu Bard. The second contract, worth €530M, has been awarded to a joint venture of Vinci Construction Terrassement and local companies SBTPC and Grands Travaux de l’Océan Indien, which will be responsible for the 6.7km of embankments and La Possession interchange. The dual carriageway will have two lanes in each direction, and has been designed to accommodate a rail line later on. Tricoire says: “The Regional council chose to not increase the personal vehicle capacity and instead to promote collective transport. The project includes lanes only for bus — and later tramway — and also pedestrian and bicycle ways.”
Recycling has never been more popular, with people encouraged to set aside paper, food, glass, plastic and more. But what about recycling our roads? Roads deteriorate over time, and rehabilitating works have to be carried out regularly — road signs warning about roadworks are a common sight. To make this rehabilitation more efficient, a time-saving and new environmentally-friendly technology has been introduced into the UK this year — having already been widely established in North America, Europe and China. The cold recycling technology involves the milling and granulation of damaged asphalt layers, which are then rebound, placed again and compacted. The cold recyclers — the machinery used in the process — recycle the underlying layers of the road. The old surface material is churned up with new binder in the machine’s mixing-chamber, before laying down the new, recycled mix immediately on the road behind. Mike Reay, managing director at Lane Rental Services which owns and operates the first UK cold recycler, says: “The recycling layer is the layer beneath the surface. Following the recycling a brand new surface course is installed — first a new structural re-strengthen layer is provided by the recycler and then a brand new layer, running surface, is provided straight after that’s been completed.”The cold recycler when operating in the project’s site needs the assistance of a second machine in order to complete the resurfacing work. “A final surfacing, after the recycling process, is always done with an asphalt paver,” says Martin Diekmann, Wirtgen’s recycling product manager. “This means that an average 4cm hot mix asphalt layer as a wearing course is paved on top of the recycled layer.”Wirtgen — the market leader in cold recycling technology — has sold 1,000 cold recycler machines worldwide so far, according to Diekmann, and this number is expected to grow.The cold recyclers can be used for thin asphalt layers or minor roads, as well as for thick asphalt or heavily-trafficked motorways. A UK firstThe first UK cold recycler made its way into the country three months ago. “I was aware of the machinery used in the States and also in Europe. I visited a site near Toulouse in France in 2015 and was impressed with the equipment,” says Reay.He adds: “This equipment has been tried and tested in the USA and Europe, therefore we had the confidence to introduce it to the UK.” The cold recycling technology was first used in the UK on a Highways England project to resurface 1.6km of the A1 at Brownieside in Northumberland. “I discussed it with AOne+ [the project’s contractor] and, obviously mindful of Highways England delivery programme requirements, we jointly decided the time was appropriate for this introduction to the UK. We ordered the machine and some trials schemes were authorised and have now been carried out,” says Reay.The Wirtgen 3200 CR cold recycler is owned and operated by Lane Rental Services and was especially custom-made for the project. Reay adds: “It has been custom-made for the UK market, not only for the 2016 works. It will be the UK machine.” The 3200 CR differs from the standard Wirtgen 2200 CR and 3800 CR on its operating width. While the 3200 CR cuts on a 3.2m width, the other two machines cut at 2.2 and 3.8m widths, respectively.
Several projects are now in execution around the world and WCN, as part of its roads week, has listed 13 worth knowing about.1) National Highway Development Program, IndiaThe $71bn National Highway Development Program was implemented in 1998 and aims at improving the road network in India.The project — being delivered in seven phases — includes the construction, rehabilitation, expansion and upgrade of nearly 56km of highway.The Golden Quadrilateral phase, completed in 2015, connects the cities of Delhi, Mumbai, Chennai and Kolkata, through a 5,846km road. The scope of the project also includes the construction of around 50,000km of roads, under Phases I-VII, Port Connectivity, and the Special Accelerated Road Development Programme for North East (SARDP-NE).Even though the development only accounts for 2% of the total length of roads in the country, it carries about 40% of the total traffic. The programme, owned by National Highways Authority of India and planned by the Ministry of Road Transport & Highways of India, started in 2001 and is expected to be complete in 2021. 2) Central to Sukhumvit Bypass Upgrade, ThailandThe $26bn project involves the construction of an underground tunnel from Central Road to Soi Pornprapanimit in Chonburi, Thailand.The four-lane tunnel will be 1,900m long and 20m wide.The project also includes the construction of four subterranean lanes, road separators, footpaths, as well as the installation of air ventilators, signalling, security and lightening systems. Additionally, a U-turn on top of the tunnel — featuring an island with dolphin sculptures — is set to be constructed.The upgrade will reduce traffic congestion, as well as provide a freeway road to the region.Construction on the project, carried out by the Ministry of Transport of Thailand, commenced in February 2015 and is expected to be complete in 2018.3) Trans-Sumatra High Grade Highway, IndonesiaThe $25bn Trans-Sumatra High Grade Highway project is set to connect the Lampung and Aceh provinces in Sumatra Island.The project, also known as Trans Sumatra toll road, involves the construction of a 2,600km toll road to be developed in 24 sections.The scope of the work also includes the construction of pavements, supporting walls, toll stations, pedestrian walkways, as well as the installation of safety systems.The development — aiming at improving connectivity and economic development in the region — has suffered many setbacks. In 2012, the land acquisition process started, but faced long delays due to disputes along the route.Construction work commenced in 2014, and the first eight sections are expected to be complete by 2019. Construction companies selected for the highway include PT Adhi Karya (Persero), PT Wijaya Karya Beton, PT Hutama Karya (Persero) and PT Pembangunan Perumahan (Persero).4) Westconnex Motorway, AustraliaThe Westconnex Motorway will provide a link between Westerm Sydney, Sydney Airport and the Port Botany in New South Wales. The US$13bn project includes the construction of a 33km road — connecting the country’s M4 and M5 motorways — to be delivered in three stages. Stage I involves the construction of 13km of road, including the construction of the M4 east link between Homebush and Haberfield. Additionally, it includes the upgrade of the Concord Road interchange and the realignment of surface roads at City West Link and Parramatta Road.Stage II includes the widening of the existing M5 East to eight lanes from the Kings Georges Road interchange, and 9km of twin tunnels. Construction in this stage is expected to be complete by 2019.Stage III involves the construction of an 8.5km, three-lane road tunnel between Stage I at Haberfield and Stage II at St Peters. Construction work is expected to commence in late 2018 and be completed by 2023.Construction on the motorway has started in 2015 and is expected to be complete by the end of 2023.The project’s contractors include Samsung C&T Corporation, CPB Contractors Pty Limited, Fulton Hogan Australia Pty Ltd, John Holland Pty Ltd, Rizzani de Eccher S.p.A., CPB Contractors Pty Limited, Dragados S.A. and sub-contractor Samsung C&T Corporation.5) Lahore-Karachi Motorway, PakistanThe National Highway Authority of Pakistan is undertaking the construction of the Lahore-Karachi Motorway project with the aim of reducing journey times and congestion. The $7bn project includes the construction of a 1,152km dual six-lane motorway to be executed in four sections. The first section involves the construction of a 136km, six-lane motorway from Hyderabad to Karachi, while the second includes the construction of a 296km motorway from Hyderabad to Sukkur.The third stage includes the construction of a 387km motorway from Sukkur to Multan and the fourth section the construction of a 333km motorway from Multan to Lahore.Furthermore, bridges, underpasses, footpaths, cycleways and service roads are being constructed.Construction work commenced in 2015 and is expected to be complete by the end of 2018.The chosen contractors for the project include Frontier Works Organization, China Railway Zoth Bureau Group and Zahir Khan & Brothers. 6) Longchuan to Huaiji Highway, ChinaThe on-going Longchuan to Huaiji Highway project has been announced in 2013 and is expected to increase mobility and provide a smooth flow of traffic.For this effect, a 368km-long and 26m-wide highway is being constructed in Guangdong, China. The $6.6bn project also includes the construction of walkways, flyovers, a 26m-wide roadbed, and a toll plaza, along with the installation of signalling and lighting systems. Construction work — by Guangdong Hualu Transportation Technology Co Ltd — is expected to be complete in 2018.7) G75 Lanhai Expressway: Weiyuan-Wudu section, ChinaThe G75 Lanhai Expressway will connect the region of Weiyuan to Wudu in Gansu, China. The $5.8bn project involves the construction of a 244km highway, including bridges, tunnels, interchanges, walkways and tollbooths. It will also include the installation of signalling and lighting systems. The expressway is being delivered in 23 sections and construction work in section 4 and 6 is now underway. Construction work started this year and is expected to be complete in 2019.8) Tolo Highway/Fanling Highway widening, Hong KongThe Tolo Highway/Fanling Highway is set to provide a good transport link between Island House Interchange and Fanling in Hong Kong.To help to achieve that aim, Hong Kong Special Administrative Region Highways Department is widening roads and constructing new bridges.The $5.6bn development also includes the construction of a carriageway, noise barriers, retaining walls, water-mains, drainage and sewerage, geotechnical and landscaping works, as well as the installation of fire hydrants and sign boards.Construction work started in 2009 and is being delivered in two phases. The engineering, procurement and construction (EPC) contract for Phase I was awarded to Gammon Construction Limited and China State Construction Engineering Limited, while a Hyder Consulting, Arup and Black & Veatch joint venture secured the design-build for phase II.Phase I has been completed and phase II is now under construction. The highway is expected to be complete by 2018.9) Altanbulag-Ulaanbaatar-Zamyn Uud Highway, MongoliaThe highway, almost 1,000km long, will connect the regions of Altanbulag and Zamyn Uud in Mongolia.The scope of the project includes the construction of a 367km highway from Altanbulag to Ulaanbaatar and 630km of highway from Ulaanbaatar to Zamyn Uud.The $5bn project — aimed at reducing traffic congestion — also involves the construction of ramps, lane dividers, pedestrian ways, as well as the installation of lighting systems. The highway is being built by the Chinggis Land Development Group (CLDG) — in a design, build, finance, operate and transfer basis. Construction work started in 2015 and is expected to be complete by the end of 2018. 10) Wenchuan-Maerkang Highway – ChinaThe $4.7bn Wenchuan-Maerkang Highway project was announced by the Sichuan Transport Investment Group Co in 2012.The project involves the construction of a two-way, four-lane 173km-long highway in Sichuan, China. It also includes the construction of tunnels, bridges, concrete pavements, service area and related infrastructure.Construction work started in 2014 and is expected to be complete in 2017.The EPC contractor for the project is CCCC Fourth Highway Engineering Co., Ltd.11) State Highways Improvement II – IndiaState Highways Improvement II project is set to improve the road network in Karnataka, India.The $4.5bn project involves the construction of 830km of two-lane highway in the first phase and 633km in the second phase.The highway is being delivered on a design, build, finance, operate, maintain and transfer basis.Construction work started in 2011 and is expected to be complete by the end of 2018.12) Woolgoolga to Ballina Pacific Highway Upgrade, AustraliaThe Roads and Maritime Services (RMS) is undertaking the Pacific Highway upgrade with the aim of reducing travel times and cost for the people.The US$4.3bn project involves the upgrade of four-lane, 155km dual carriageway between Woolgoolga and Ballina on the North Coast of New South Wales. The development — being developed in 11 sections — includes the construction of 10 grade-separated interchanges, access bridges, overpasses, viaducts, cross-drainage bridges, service roads and a 1.5km new four-lane Harwood bridge over the Clarence River.The scope of the work also includes the installation of signalling and safety systems. The latest contract for the project was awarded to Ferrovial and Acciona consortium in July 2016 for the design-build of Harwood Bridge.Works on the first and second sections are underway. The entire project — expected to reduce travel times by up to 25 minutes — is scheduled for completion in 2020.13) Pan Borneo Highway Upgrade, MalaysiaThe Pan Borneo Highway Upgrade project consists in the upgrading of 1,663km of carriageway from Borneo States of Sarawak and Sabah in Malaysia.The highway is being upgraded from a single-carriageway into a dual-carriageway.The scope of the work also includes the construction of bridges, pedestrian ways, and other related infrastructural facilities as well as the installation of signalling and safety systems.Lebuhaya Borneo Utara Sdn Bhd is the main contractor for the $4.2bn project — being developed in different stages. Construction work started in 2015 and is scheduled for completion in 2023.* For more information on road projects, visit Timetric's Construction Intelligence Center.
If you believe the old song, the M25 motorway that circles London is ‘The Road to Hell’. But while many motorists may be inclined to agree with that sentiment — particularly during the coming bank holiday weekend — there are plenty of roads around the globe that offer much more than traffic jams and suspect hotdogs from service stations. From those that take in remarkable natural scenery, through to those constructed using innovative technologies — we look at some of the world’s most interesting roads.1) The Atlantic Ocean Road, Norway
“We did it. We – the Vogel family from Boise, Idaho – did it. We did the impossible, and I couldn’t be happier that we did,” wrote Nancy Sathre-Vogel, in her family blog, when she and her family reached Ushuaia, in Argentina.Eight years ago, John and Nancy Vogel left their teaching jobs, took their twin boys out of school, bought two single bikes and a tandem and embarked on a journey to cycle the Pan-American Highway.The Pan-American Highway is a network of roads, extending from Prudhoe Bay, Alaska to Ushuaia, Argentina. According to the Guinness World Records, the 48,000km highway, which runs through the North and South American continents, is the world’s longest ‘motorable road’.The highway comprises official and unofficial sections. The official section runs from Nuevo Laredo, Mexico to Buenos Aires, Argentina, while the unofficial sections can be found to both the north and south of the official route.The route — including the official and unofficial sections — spreads across 14 countries: the USA, Canada, Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, Chile and Argentina.However, if you are thinking in cycling or driving all the way down until Ushuaia without stopping — except to rest, sleep or eat — take that out of your mind.The route is interrupted by a 160km-wide break, named the Darién Gap, between Central and South America.The Pan-American Highway is for many the ultimate road trip and here — as part of the WCN’s Roads Week — we provide you with everything you need to know, so you can start, if you fancy the challenge, your ‘little’ adventure.
As technologies for road construction advance, so too do the highways that connect cities, countries, and even continents. We look at the seven longest roads in the world today.1) Pan-American Highway, American continent
As the seventh-largest state in the US by area, Nevada needs its roads. And the largest freeway construction project in the state’s history is currently underway.Called Project Neon and commissioned by the Nevada Department of Transportation (NDOT), the undertaking covers a 3.7-mile corridor through the heart of Las Vegas and will cost almost $1bn in total. It includes the approach spiral Interstate 15/US Highway 95 interchange — otherwise known as the Spaghetti Bowl — where around 300,000 vehicles pass through daily, conducting 25,000 lane changes every hour.Design lead on the project team is Atkins, who are managing all design and engineering services, including the project’s Active Traffic Management System (ATM). This is key to realising the NDOT’s overall construction plan, which prioritises safety and driver awareness.It involves keeping motorists informed with real-time information and updates — before, during and after the construction of the freeway project. Atkins has previous experience with this type of technology, having designed freeway management systems for more than 80 miles of roads in Southern Nevada in the past.The dynamic message signs positioned over the freeways provide information on alternative routes, any traffic incidents and restrictions, and instructions regarding lane control and variable speed limits.The project is indicative of more than one current trend in the road construction sector, says Atkins.“As a design, engineering and project management consultancy, we have seen an increase in the use of public-private partnerships (P3) to fund and operate projects, as well as an increase in design-build as the method for project delivery,” says Barry Schulz, chief operating officer for Atkins, North America.
You might think that tunnels are always built by professionals, with an obvious and practical purpose — to transport people, to reach a deposit of coal or diamonds, to transport water, and so on. For some, however, digging a tunnel is a hobby, a distraction, an escape, a way of expanding their houses underground or even a way to exercise — we look at some of the tunnels built by ordinary people around the world. 1. Elton Macdonald
Adding capacity to the over-tasked wastewater system in Mexico City, an alignment through changing ground conditions is a likely candidate for Robbins’ Crossover TBM, Nicole Robinson reports.In the mountains northwest of Mexico City, the soft rock is self-supporting and very consolidated, a dream to mine. "Even the face is self-supporting," says Roberto Gonzalez, Robbins' general manager in Mexico. "You could use a normal backhoe and excavate like that. It's a beautiful ground to bore."But the alignment crosses valleys of tuff, faults and finishes with a stretch of soft ground with low cover. This is the scenario for Túnel Emisor Poniente II (TEP II), or the English translation of West Drainage Tunnel II.Conagua, Mexico's national water commission, is building the 5.9km-long tunnel with a 7m i.d. to reduce flooding in the area, and increase wastewater capacity. Across three municipalities, some 2.1 million people will benefit from the tunnel project.The contractor joint venture of Aldesa, Proacon and Recsa chose an 8.7m diameter, dual-mode type machine capable of "crossing over" between rock and EPB. With the August 2015 tunnel boring machine (TBM) launch on TEP II, manufacturer Robbins has supplied its first Crossover machine in Mexico.End gameRobbins draws comparisons to the Kargi Kizilirmak hydroelectric project in Central Turkey. The design of the TEP II machine was based largely on experience from past projects, and that TBM in particular. While initial reports on the Turkey project showed fractured hard rock, Robbins explains, within 80m of launch the geology became substantially more difficult than expected, consisting of blocky rock, sand, clays and water-bearing zones. The machine required multiple bypass tunnels and major modifications before it could resume excavation.Robbins says these modifications proved instrumental to the design of its Crossover TBMs, including the TEP II machine.In Mexico, the contractor JV expects to convert the machine from hard rock to EPB mode due to changing ground conditions in the last kilometre of the alignment. "Initially the proposal was a hard rock machine but they found they have 800m of water-more EPM conditions-that's the reason we proposed a Crossover," explains Javier Alcala, job site engineer for Robbins on TEP II.The ground conditions at TEP II are complex, from competent to weathered volcanic rock to clay, and sand. The final 800m is also the portion of the alignment with the lowest cover, some 12m, and the most populated. This is one of the reasons for using a Crossover machine. The rest of the drive has between 50-60m of cover on average with some stretches up to 150m."We try not to convert unless it's completely necessary because you stop, you have to drain the screw conveyor inside the machine, and you have to make a lot of changes, for example on the cutterhead," Robbins' Gonzalez explains.As an open mode machine boring in rock, the TBM is equipped in the event of entering running ground, he says. "These closure doors are able to maintain the material in the cutting chamber. They're just a safety." In smaller valleys of tuff there is potentially some water, but it's unknown for now, he explains."For these cases we believe that these closure doors will be held to see what we have to do with the material, if we have to consolidate in the front."Tight fitAldesa's Castillo says one of the biggest accomplishments on the project so far has been organising the logistics in such a small work space-fewer than 10,000 sq m. The JV excavated a 30m deep launch shaft supported by 800mm-thick Milan walls (slurry walls), and used on-site first time assembly, he says, to start excavation as soon as possible.Once assembled by gantry crane, the machine bored 100m before adding back gantries. When completely assembled the machine has nine gantries for a total length of 1,030m.At the time Tunnels & Tunnelling visited the project, the crews were still adjusting to having the full machine in operation, and had only recently started using the continuous conveyors for muck.The TBM was mining through a transition zone between tuffs and dacites, and had excavated 435m by mid November 2015. At the time of publication the TBM has bored 1,417.5m, which equates to 945 rings. The best day has seen an advancement of 42.8m and the best week is 185.1m. Robbins' Mexico office reports the TBM has reached softer geology and is boring very well.Tunnelling is expected to finish within this year and a second lining of reinforced concrete will be installed following excavation to extend the life of the tunnel. "Once we arrive to the final bit, it's a very close curve of 400m radius," Alcala explains.The tunnel alignment ends along the rivers of San Javier and Xochimanga in Atizapan de Zaragoza.
With a burgeoning market for hydropower development, tunnelling work is seeing an uptick in South America’s third largest country. Nicole Robinson looks at two recent projects.The World Bank released a report in 2010 to help the Peruvian government in assessing the potential role of hydropower in the energy sector and the measures that could be taken to encourage its continued development as appropriate. Hydropower has been the major source of electricity in Peru, traditionally supplying more than 80% of requirements, and serving as a source of independent generation for major mines and industries.However, as the report explains, in the early 1990s efforts turned to natural gas and the government began providing incentives for its use in power generation: "This resulted in a virtual moratorium on hydropower development as a result of the very low price of natural gas (below economic cost)."Over the next decade, with the development of export markets for gas and increased attention to the impacts of climate change, the Government returned its attention to hydropower. The Peruvian government completed its National Energy Plan 2014-2025, which calls for electricity to comprise 60% renewable sources by 2025, with 54% coming from hydropower.The International Hydropower Association called Peru a regional leader in small hydropower projects. In its 2015 Hydropower Status report it estimates Peru has hydropower potential of at least 70GW, "of which only 3.8GW have been tapped so far."In 2014 Peru added 199MW, ranking it among the top 20 countries installing capacity at number 17 —Canada comes in at number three and the US at number 16.The market potential for hydro construction in Peru has captivated the likes of Odebrecht, whose subsidiary Empresa de Generación Huallaga (EGH) is developing the 462MW Chaglla power plant, which will be country's third biggest hydropower project upon opening, scheduled for this year.Norwegian company Statkraft opened its ninth hydropower plant in Peru, the Cheves Hydropower Project, this autumn. "The opening of Cheves consolidates Statkraft's position among the largest power producers in Peru," says Statkraft's executive vice president of International Hydropower, Asbjørn Grundt. "It also underlines our ambition to further strengthen our position as a leading international provider of pure energy. Our efforts in South-America play a very important role in this strategy,"Chaglla’s bypassLocated between the districts of Chaglla and Chinchao, some 420m from Lima, the Chaglla Hydroelectric Power Plant has 406MW of installed capacity. The plant is the result of an investment made by Odebrecht Energia of $1.bn, with support from the Brazilian Development Bank, and the Inter-American Development Bank, among others.The project will also feature a small power house, including a power transformer with an output of 6MW. "Chaglla will be one of the largest hydroelectrical power plants in Peru and it will represent almost 8% of the current consumption of energy of this country," says Erlon Arfelli, manager of Odebrecht Energia in Peru.Construction started in May 2011, with Sandvik supplying six DT820-SC tunnelling jumbos for the excavation at Chaglla. Underground construction includes a spillway composed of three tunnels for a total length of 2,838m, 14.5m x 12.6m-high. The 14.7.km-long intake tunnel is horseshoe-shaped with a 7.6m diameter.One of the most important works in the project is bypassing the Huallaga River, which contractors performed through a trunk tunnel of 12.5m diameter, 1,125m long. Odebrecht says the work concluded nine months prior to the scheduled date. The bypass tunnel, a significant step for the project, allowing the dam to be constructed in the former riverbed.Odebrecht says EGH began filling the reservoir on September 1, 2015, and expects the process to last between 45 and 60 days. The project's lenders appointed Mott MacDonald in 2013 as independent engineer to monitor construction.
Metro projects and hydropower schemes continue to drive India’s tunnelling market, and more opportunities are yet to come but challenges remain in the competitive market, Bernadette Ballantyne reports.Until the turn of the new millennium, India's tunnelling market was dominated by hydropower and irrigation tunnels, many of which meant drilling into the challenging geology of the Himalayas. "These are the toughest ground conditions in the world, closely followed by the Andes and then the Alps," says Manoj Verman, president of the Indian National Group of the International Society for Rock Mechanics (ISRM) and an independent consultant on tunnelling and rock mechanics. "The geology is very varied.It is not uncommon to encounter weak zones, shear zones, fault zones and water in the same path," he says noting that the high overburden stresses from the mountain can also cause problems. Combined with the inaccessible nature of some of the locations and the climatic extremes that include snow and flash flooding, working conditions are inhospitable at best and impossible at worst. It is clear to see why projects here are so challenging.Early TBM hurdlesDealing with the hard and changeable Himalayan rock has traditionally been a drill and blast affair, but the use of tunnel boring machine (TBM) appears to be gaining momentum despite an inauspicious start. "In mountainous regions TBMs have been used and the first three projects were a disaster," says Verman. "There is frequently changing geology and if a TBM goes fast it can get stuck and that is a nightmare. If the height of the mountain is very high it stresses too much and if the rock is soft then it squeezes, under the same height of overburden if the rock is strong then it will burst so these two are extreme cases and they both happen under high stress."An early example of a stranded TBM was on the Dul Hasti hydropower project in the Kishtwar district of Jammu and Kashmir, which began preliminary construction in 1985 and became operational in 2007. Shear zones regularly crossed the 9.64km head race tunnel alignment and water seepage was high leading to tunnel roof collapses that eventually buried the TBM, leaving it beyond salvation.Better progressHowever there have been some more positive breakthroughs. In June 2014 contractor and TBM manufacturer Seli announced that it had completed 14.7km of tunnelling on the Kishanganga hydropower project in Kashmir, mainly for construction of the 12km headrace tunnel. Revealing average rates of over 400m per month and a maximum of 816m in a single month, the scheme has been widely recognised as a huge breakthrough for mechanised tunnelling in the Himalayas. "This tunnel was a tremendous success," says Verman pointing to other forthcoming schemes that are planning to use TBMs. Client THDC India has appointed Hindustan Construction Company (HCC) to use a TBM for delivery of a 10m diameter, 12km long head race tunnel for the 444MW Vishnugad-Pilpakoti hydropower scheme in Chamoli in the state of Uttarakhand. The TBM is scheduled for delivery and assembly on site in February 2016.Long awaited success in the mountains combined with a huge demand for TBMs to build a growing number of city wide metro schemes, means that TBM manufacturers are upbeat about the prospects. TBM manufacturer Robbins established its Indian subsidiary in New Delhi in 2005."We started by supplying 10m double shield TBMs to contractors for an irrigation water supply tunnel which is 43km long. It would be the world's longest tunnel without intermediate access once completed," says Kapil Bhati, general manager for Robbins India, noting that the company's 10m-diameter machines are the largest in operation in India today. "The tunnel will take the water from a river and then over to a drought affected areas irrigating 500,000 hectares of land and further providing drinking water. We have completed around 25km as of now with two TBMs. We are still continuing and expected to complete 2.5 years from now," he says.Of course such a huge job has not been without its challenges and although boring of the outlet began in 2007 access to the inlet end was not available until 2011 due to land acquisition issues."After that advancements were pretty good even with geology being more difficult than anticipated. We are still doing around 300m/month average on each side of the tunnel so the production average is good in spite of the hard rock and tough geology," says Bhati.Another water tunnel transferring flows from the same river, is also underway using a third Robbins 10m-diameter machine. The tunnel is half way through with three years to go, says Bhati. A fourth 10m-diameter machine is also building a 12km water transfer tunnel.Metro growthAs these schemes roll on, Robbins has also been busy supplying and supporting machines for metros in India's bustling cities. "Soon after the irrigation tunnels the metro projects started," says Bhati and the company began by supplying machines to Delhi and then Chennai. "Delhi Metro was totally soft ground so we supplied a spoke type of earth pressure balance (EPB) machine. Those machines performed very well and had very good advance rates."The geology of Chennai is mainly soft but there are a couple of areas where there is rock or mixed ground and then we have supplied a mixed face EPB machine for that geology," he says."The result has been a more challenging bore in Chennai with rock at the bottom and soft ground at the top combined with ingress of water. Cutter changes and interventions were challenging but we have still been successful. There are around 200m left to bore."In Jaipur which is currently building the first phase of its metro starting with a 12km east-west connection, 2.8km of which are underground, the company met with soft ground. "The contractor had two old Robbins machines in stock so we refurbished those machines for the contractor and those are being used. The main challenge here is the heritage structures over the top. It is an old city," he says noting that in the areas where the metro transitions from elevated to underground there is just 5m of cover and yet the marginal tolerance is just 1mm.Tip of the icebergThese are just the tip of the metro iceberg. "Right now there are metros being built in New Delhi, Chennai, Calcutta and Bangalore. Elevated and underground both," says Sanjib Bhattacharya, chief of TBM tunnelling at ITD Cementation India, which is comprised of Italian Thai Development Public Company Limited with the Indian branch of the UK's Cementation. In his 22 years with the company Bhattacharya has delivered 50km of traditional tunnelling with NATM and 21km of TBM routes. "We just completed 7km of TBM tunnelling in Delhi. I was the project manager and out of 7km there were four EPB TBMs, two mixed shield and two soil all from Herrenknecht. In Delhi out of 36 machines, some 19 were Herrenknecht," he says. The Delhi metro is now undertaking its third phase of construction which will result in a further 160km of new lines 54km of which are underground. At its peak in mid-2014 there were 26 TBMs working simultaneously. The tunnelling is over 80% complete as Tunnels and Tunnelling goes to press and has not been without its challenges. Bhattacharya says that one particularly tough section was a 1.25km drive that ran beneath Delhi airport's runway for a distance of 400m meaning that the contractor was not able to carry out geotechnical investigations."This was very unpredictable because the geological data was not there. We designed our machine cutterheads and cutting tools on the basis of available geological parameters. It was around rock, we encountered quartzitic rock of around 200-210Mpa. Very, very hard. So in accordance with that we designed our machine to 250MPa. But unfortunately when we entered the airport area where the survey was not possible we encountered 350MPA," says Bhattacharya. As a result the construction costs ballooned from USD 14 to USD 15 per metre to around USD 35 as the hard rock quickly ate up the cutters. "It was a huge cost and meant that we were only getting four or five metres per day."As a result progress on this section was two to three months behind schedule, says Bhattacharya, however he points out that better progress on another drive where they avoided the rock and used the soil EPB machine made back the time.Despite having taken cores every 50m the nature of the airport site prevented investigation in this area and Bhattacharya says that the client accepted this when the contractor made a claim for the additional costs. "In India contracts are very rigid. 400m survey was not possible so we put a claim in and this was (logically) accepted by DMRC as the data couldn't be got in advance."Critical geological dataAs this experience shows, obtaining geological data is critical for any tunnelling project and is an area where Verman says that clients themselves need to put in more effort in the planning stages if they want to see their projects succeed. "The biggest lesson I would offer clients is 'please investigate more'. What is absolutely lacking in the country is proper site investigation or geotechnical investigation before the project," he says pointing to a World Bank study which he led five years ago which reached the same conclusion. "In state of the art projects 3–5% of cost is spent on investigations but in India it is not even 0.5%. People always say they have had geological surprises. They are surprises because they are not investigating. That is the biggest lesson that should be learned.""I fully agree," says Bhati. "There is hardly any sufficient data available before the tendering process commences. We understand regarding areas which have the limitations like Himalayas wherein the cover above the TBM is as high as 1 to 2km. On the other hand, water transfer tunnel projects or metro projects have the accessibility of lands which clients want to cut short by not providing the proper information or doing proper geographical mapping which results in the award of the tender to the contractor as it is," he says."The contractor in turn has to gather that information by himself which takes time therefore delaying the project and losing more time. Better and earlier information on geological details allows the manufacturers to design the machines and give them provisions to equip the machine to encounter all the problems in front."One of the side effects of this is that projects are less attractive to international contractors who are not prepared to take the risks pushed onto the contractors under the design and build arrangements. "For the time being, due to aggressive local competition and actual contract versions comprising unacceptable risks for the contractor, we refrain from tendering for tunnel projects in India," a spokesperson for contractor Strabag says.Yet ironically clients are demanding that international firms participate in main contracts. "Indian clients are putting a condition [in place] that the tunnelling manager must be an expert from outside of India," says Bhattacharya who says that the international financing provided to the metros also pushes for European consultants to be involved."It is true that they have more experience than us but the fact is that we are building experience. I have a team now running four TBMs simultaneously and now I am looking at Mumbai and Kolkata. We have the resources. Only problem is that the Indian companies don't have the technical credentials so they can't pass the technical bids so that is why we are making JVs."However he says that this is changing and that for smaller bores of 1-2km Indian contractors are wining projects without international partners. Another advantage that local firms have is their proximity to clients and their long term market positions which mean that local companies are more willing to accept delayed payments through claims. International firms however see this as too risky.One way of reducing risk, says Bhati is to have the TBM manufacturer support the project through its life, not just at the beginning. "Most of the time delays are because manufacturers are not supporting the project and the contractor is not capable of coping with the difficult geology. On most of the jobs what we are doing we are supporting them on execution on a per metre basis," he says.This strategy has been particularly important to the Bangalore metro for which delays have been widely reported in the local media. Mumbai Metro Line three"On Mumbai Metro there are seven packages and we got package four," says Bhattacharya whose firm ITD Cementation are in joint venture with Continental Engineering Corporation of Taiwan and Tata Projects. Financial bids were opened in October and Tunnels and Tunnelling International understands that the client Mumbai Metro Railway Corporation is currently scrutinising the project budget which is lower than the forecast costs. One of the major issues which will be faced in the execution of metro tunnels in Mumbai city will certainly be the rock strata which will push up the tunnelling costs. The entire 32.5km line is underground."Geological survey suggests 90% rock which will vary from 50 to 150MPa," says Bhati who has first-hand knowledge.Contracts for this line are yet to be signed . Other MetrosMumbai may be the next major project set for award but there are many more on the horizon. "Phase four of Delhi is coming with 90km of tunnelling. Bangalore phase one is about to complete and phase two is coming next year. Chennai phase three coming next year. Kolkata has another two underground packages coming," says Bhattacharya also pointing to forthcoming schemes in Lucknow in Uttar Pradesh, Hyderabad and Puna."The market is very promising perhaps one of the best in the world at this time, says Verman. "Now is the time that the country has to start moving into delivering infrastructure in difficult areas. Many projects are already sanctioned but procedures are such that they are not tumbling out in the way that we expected. However remain very optimistic. I am expecting 2016 to be a crowded year."Data from the Timetric Construction Intelligence Center places the value of work underway with a tunnelling element at USD 31bn however given the scale of projects planned — Verman says there are 3,000km of tunnels in the pipeline, the figure seems likely to rise substantially over the next five years."I was involved in planning a railway through the Himalayas from Rishikesh to Karnaprayag, 125km long alignment of which 105km is in tunnels so that is the kind of project you are looking at and for this kind of distance you have to use TBMs, especially for the longer tunnels," he says.Bhati of Robbins points to four main growth areas for the TBM tunnelling market. "We have hydropower projects in the pipeline which we see being awarded in 2016 and a couple of them will be using heavy provision of TBM. Then the metros like Mumbai which will be awarded in the next few months.Bangalore and Chennai are planning phase two. Seeing the success of Delhi, Bangalore and Chennai everyone sees that it is the best solution possible. For the next 10-15 years one city after the other will keep having metros come up," he says.Water transfer tunnels to divert much needed resources is also a priority, as are road tunnels. "These are the future. People have realised that there is limited space available above ground so we have to go under. There is a 22km underground tunnel in Mumbai which is going to come from the southernmost part of the city through the coast to the airport. It is entirely underground and will be about 12m diameter, and has now been approved.”Learning from the pastExpectations are therefore high for India's growing and maturing tunnelling industry, but challenges remain and Verman urges government to learn from the past in terms of better planning and reducing bureaucracy so that contractors are able to get on and deliver. "There are huge projects coming forward and government should support this industry and nurture it because it is in the government's interest that these projects are built.”
Repairs are finished for giant TBM ‘Bertha’. Patrick Reynolds reports on the two-year-long process.Bertha, better known as Big Bertha, is a 57.5ft (17.53m) diameter tunnel boring machine (TBM) built in 2013 for the Washington State Department of Transportation’s (WSDOT) Alaskan Way Viaduct Replacement tunnel in Seattle, a JV between STP and local firms Frank Coluccio Construction and Mowat Construction, and also HNTB Corp and Intecsa-Inarsa.The machine, built in Japan by Hitachi Zosen Sakai, broke down after an alleged encounter with a steel pipe, damaging several cutting blades, taking two years to fully repair it.By the beginning of 2016, the giant TBM Bertha in Seattle is expected to restart boring on the delayed, central waterfront section of the USD 3.1bn Alaskan Way Viaduct Replacement project, following repairs to the machine.To prepare, Bertha has been undergoing an unusual, if not unique, experience for any TBM, not least the world's largest: she is being buried to commence boring.A 120ft- (36.5m-) deep shaft was constructed to reach the TBM, allowing its vital front section to be brought to the surface for repairs. Following the work, the TBM was reassembled, the cutterhead was turned and other no-load tests were completed. The last task is load testing to relaunch the TBM for its drive below the viaduct.To that end, the shaft has been backfilled with sand and controlled density fill, allowing Bertha to bore once more. Slowly. For a few hundred feet only, at first.Even though the TBM was first launched two-and-a-half years ago, it still has most of its relatively short, 1.7mile- (2.7km-) long tunnel drive yet to finish.The TBM was stopped in a ‘safe haven’, which is a pre-planned, jet-grouted zone designed to allow last checks and adjustments before Bertha bored below the elevated highway again.Fortunately, perhaps, the troubles that brought Bertha to a halt in late 2013 occurred shortly before the machine moved under the seismically-weakened viaduct. Performing a TBM recovery under the viaduct could have been much more difficult. Even outside that zone, the investigation and repairs undertaken presented “a significant challenge”, says Chris Dixon, project manager with Seattle Tunnel Partners (STP), the designbuild JV contractor comprising Dragados and Tutor Perini.Coincidentally, Bertha is preparing to resume boring around the time when, as per the contractor's original schedule target, tunnelling was to have been finished. Bertha is expected to emerge around the beginning of 2017, according to the latest construction schedule issued in November 2015 by STP. The entire Alaskan Way Viaduct Replacement project is to be finished by April 2018.But while the focus shifts from repairing the Hitachi Zosen TBM, and with the tunnelling industry, the coastal city and the state hoping for untroubled progress ahead, the beginnings of legal fights and insurance liability debates over blame have started.The complex arguments over fault, liability and financial consequences are contested between the project owner —Washington State's Department of Transportation (WSDOT), the JV contractor and TBM manufacturer, and various insurers. Lawsuits have been submitted over recent months.Over the two-year standstill, STP and Hitachi Zosen received no payments from the client related to the TBM recovery costs. STP has only received payments for progress achieved on the many other continuing works, such as around the tunnel portals and concreting of the decks within the tunnel bore so far.But, finally, the project looks set to change gear as Bertha prepares to build the rest of the 52ft (15.85m) i.d. tunnel below the waterfront during 2016.Rise of the TBM optionThe aim of the redevelopment project at the waterfront is to improve Seattle's overall transport and economy. Debate over how to do so ran for years, and a host of studies were performed on realizing a fresh infrastructure vision and removing the seismically vulnerable viaduct on state highway SR99.Back in 2008, the leading alternatives did not include the TBM option, especially to construct a large single tunnel, although all possibilities had had reviews.The long-term vision was to create an 'incredible' waterfront for the city — ideally one with minimal traffic on the surface. Putting as much as possible underground was elected to be the way forward, and the deep bore option became a late stage winner in early 2009.The JV contractor proposed building the tunnel with an earth pressure balance TBM, and aimed to have the tunnel open to traffic before the end of 2015. The owner's contract performance deadline was late 2016 for substantial completion of the SR99 tunnel, with performance bonus and penalties either side of the target.STP hired Japan's Hitachi Zosen to manufacture and supply the EPB TBM. Washington state set up an Expert Review Panel (ERP) to look over key assumptions in cost estimates, identify risk during the construction phase, comment on development of funding sources, and consider the project's schedule.Launch, then stopIn late 2011, construction staging commenced in Seattle and manufacturing efforts got underway for the TBM in Japan. The TBM was assembled in dry dock in late 2012, before it was shipped across the Pacific Ocean to Seattle.Many activities in both Seattle and Japan were on the critical path of the project schedule, the ERP cautioned in its February 2013 report. It issued an opinion that the target launch date of June 2013 was not expected to be achieved.However, the TBM was assembled in Seattle over April-July at the south end of the tunnel alignment, and then formally launched at the end of July 2013.Bertha's 2-mile- (3.2km-) long drive was expected to take about 14 months. In its following report of February 2014, the ERP noted that early operation of the TBM had delivered better than expected performance.The tunnelling plan was to set off slowly. The TBM would stop early to perform planned maintenance and checks at key ‘safe havens’ along the first 1,500ft (457m) of the northward drive before then diving below the elevated highway.By early December, and despite the late start in mid-year, the shield had advanced more than 1,000ft (305m), reaching where it was expected to be against the schedule, the ERP reported. The panel also said the shield had advance more quickly than expected by the project team, and pulled back time against the schedule. But then trouble struck. The machine overheated and progress slowed as “unanticipated and increasing resistance was experienced”, WSDOT reported. The TBM was stopped on December 6, 2013.At that point, as per the contract between STP and Hitachi Zosen, STP was about to take ownership of Bertha from the TBM manufacturer. Hand-off was planned to follow after the first, proving and settling, stage of tunnelling, constructing the tunnel up to Ring No. 200, as WSDOT had noted in a statement on December 5, and Dixon confirms.Investigation and recovery planWith Bertha stopped under cover of 60ft (18.2m), the contractor lowered the high water table around the TBM. Drilling wells to a depth of approximately 120ft (36.5m), water pressure was reduced to enable the TBM crew to safely start inspecting the machine’s excavation chamber in early January 2014. Probe holes were also bored ahead to check for potential obstructions.The investigation of the top 15ft (4.6m) of the chamber revealed a piece of 8in (200mm) diameter pipe — a section of steel well casing — in a cutterhead opening, WSDOT reported at the time.In late January, a programme of hyperbaric interventions allowed inspections into more of the excavation chamber. Many of the cutterhead openings were found to be clogged, which was then viewed as the more likely cause on the mining difficulty and not major obstructions — none of which were found inside or in front of the TBM, WSDOT said in February 2014.Then, as a trial, STP restarted the TBM to build a ring. More high temperatures were recorded, like before the December stoppage. Investigating further, STP found damage to the main bearing seal.Laura Newborn, spokeswoman for WSDOT, has expanded on the initial information, explaining to Tunnels & Tunnelling North America that the well-casing was found inside the material blocking a cutterhead opening."The cutterhead was clogged," she says. "The piece of metal was not blocking the opening."She adds that the metal detected in front of the cutterhead turned out to be the nose of the cutterhead. "There was no metal found in front of the machine," she adds.WSDOT said at the time that the steel pipe found in the cutterhead was a well casing, installed in 2002 and used by geologists to study groundwater flows following the 2001 Nisqually earthquake. The owner added that location of the pipe was included in reference materials in the contract. However, according to JV contractor member Tutor Perini's third quarter-2015 results, presented in its 10-Q filing to the Securities and Exchange Commission, STP claims the steel pipe to be a "differing site condition that WSDOT failed to properly disclose." Tutor Perini added that the Disputes Review Board had said the pipe was a differing site condition, but noted that WSDOT has not accepted the finding. WSDOT's spokeswoman told Tunnels & Tunnelling North America the "root cause of the damage to the TBM is still under investigation."Reach and repairSignificant repairs would be needed at the TBM. The ERP said the stoppage to TBM tunnelling would throw out the project schedule by some months. It called on the client and contractor to stay away from debates over blame and financial liability, and keep their focus on investigating and resolving the technical problems.In its February 2014 report, the panel advised that the contractor be given appropriate time to develop a recovery plan. "Returning the TBM to operation should be everyone's primary objective," it added.During the halt in work, the contractor undertook wider inspections and also maintenance work, including replacing damaged cutter tools. But the discovery of damage to the bearing seal system also called for replacement of the main bearing. With such major works required, it was decided that the TBM could not be repaired underground. The shield had to be accessed from the surface and opened up to retrieve the cutterhead and cutter drive unit. STP developed a recovery and improvement plan, which it believed would allow the repaired TBM to resume tunnelling in March 2015.STP's plan was to sink a large diameter access shaft a little ahead of the halted TBM. The 80ft- (24.3m-) wide shaft was built through much of 2014 and readied to receive the TBM.The dormant machine was restarted in February 2015. It broke into the shaft and came to a rest on a concrete cradle, cast on the base of the shaft. Hitachi Zosen hired a heavy lift contractor to extract the front sections of the TBM, and this was done in late March. Mammoet designed a modular lift tower capable of sliding over the 120ft-deep shaft and repair area.Soon after, in its April 2015 report, the ERP said that while reasons for the TBM problems were not yet clear, and also were subject to ongoing legal and commercial debates, the contractor had been constructively using the stoppage period, adding that STP planned "to apply some lessons learned" from the tunnelling work done up until then. The ERP, through its discussion with project parties, said in its April 2015 report that the recovery plan for the TBM "appears to be viable," adding it was reasonably confident the machine could be repaired.The panel added that STP and WSDOT had shared information — "without direction from WSDOT" — on how to improve the TBM's function. "It appears that many of WSDOT's comments have been considered in the redesign and repair plan," ERP said.WSDOT had formed its own Restart Team to monitor the contractor's work and risk and mitigation efforts. "Fully disassembling and assessing the machine was always the key to determining how long the repairs would take," said Dixon, in mid-2015.Revise and rescheduleThe ERP commented the stoppage was "unusually long" due to the scale of investigation and repairs needed, and the area was a congested urban environment with geotechnical challenges. Working around the core recovery challenge, the contractor examined and re-programmed a number of other tasks for the tunnel, such as manufacturing all of the precast segments needed for the entire tunnel and storing them, ready for use. Other re-programmed construction activities, helping to offset some of the effects of the TBM stoppage, have included, says Dixon: • Completing the underground structure of the south operations building; • Constructing the interior cast in-place concrete roadway structure within the completed portion of the bored tunnel; • Advancing north and south cut-and-cover sections enough for their handover to other works packages; and, • Redesigning M&E systems, installing and commissioning them faster in sections instead of keeping with the original plan of doing everything in one go after excavation is completed. By the time of ERP's report in April 2015, the panel had learned the contractor then expected a later restart of the TBM — in August.It also noted, and as STP and WSDOT have continued to say, the rescheduled completion target cannot be determined until after the TBM has been restarted, has bored again but also has been re-checked at the last safe haven.In mid-July, installation of the new main bearing commenced. But the schedule was pushed back further with TBM restart then pencilled for late November.Hitachi Zosen completed the above ground repair works in mid-August, allowing the heavy sections to be placed back down the shaft for reassembly at the open front end of the TBM. Finally, in late November, the cutterhead was rotated and system checks performed in a "no load" test.With those successes, the access shaft finally could be backfilled. The next crucial step for Bertha are the pitstop checks. All being well, the big bore will proceed below Seattle's waterfront over the coming months.* This is a version of an article that first appeared in Tunnels & Tunnelling.
London’s Crossrail project not only now has an official name — it was revealed the the cross-city rail system will be called the Elizabeth line — it is also less than a year away from the start of the first testing phase.It was a year ago that tunnelling was completed — using two tunnel boring machines (TBMs) called Victoria and Elizabeth, continuing with the regal theme.That followed three years of tunnelling that started in May 2012, and now, four years on, the project is approaching 75% complete, says Crossrail project manager Nisrine Chartouny.The first services will start in May 2017 with trains running from Shenfield to Liverpool Street. The tunnels below the capital and ten new stations in central London will open in December 2018 and the line will open fully in December 2019, when it will connect Reading and Heathrow in the west with Shenfield and Abbey Wood in the east.It’s the largest transport project in Europe, and will add around 10% to the capacity of London’s rail network, serving 40 stations — ten of which are new for the project. An estimated 200M passengers will ride the line each year.
Plans for a Helsinki–Tallinn undersea rail tunnel are a step closer to reality after Finnish and Estonian ministers signed a memorandum of understanding (MOU) earlier this year.The MOU binds the two states to further investigate the viability and economic impact of the tunnel’s construction.The 50-mile undersea rail tunnel has been on the table for almost a decade, with multiple studies considering the potential for socio-economic development between the two cities.According to a study financed by the European Union EUBSR Seed Money Facility, published in February 2015, the project is set to be a success.Predicted to treble travel and boost trade, the tunnel, if built, will be one of the longest underwater railway tunnels in the world, serving four million people living within a 200km radius of both capitals. It will also carry about half of future cargo traffic in the area.25,000 daily commuter trips are to be expected in the first ten years after the opening of the railway, which promises improved accessibility and reduced commuting times from the current two-and-a-half hours by ferry to a 30-minute journey. The revenue generated by passenger traffic would amount to €67bn by 2080.Trains will be able to carry 800 passengers each and cargo with a total capacity of 96/TEU, reaching speeds of 250 km/h.Expected to take eight to ten years to be finished, the total cost of the development can vary between €9bn and €13bn and construction work can start anytime between 2025 and 2030. Further plans include the construction of a €3.6bn Rail Baltica high-speed train line to link Finland, the Baltic States and Poland, improving the connection between central and northern Europe.Socio-Economic ImpactA decisive factor on the tunnel’s construction is its ability to boost economic activity in the Nordic region.The region can become one of the significant centres in Northern Europe, as the two cities house more than 2.5M inhabitants and see over 7.5M passengers travel annually by ferry for business or tourism purposes. By 2080, the total number of passengers between the two cities is expected to reach 41M.Although transport via the new tunnel is slated to bring a 1–3% increase to Finland’s GDP within 20 years in operation, that will not be replicated in Estonia, Latvia and Lithuania, which will see only an increase of 0.5% in GDP.Both countries are expected to collect the benefits of the wider consumer market and shared labour market that the tunnel would open to.The European study concludes: "The figures also show that direct and indirect benefits during the construction and operation period to the economy of both countries are remarkable. “The competitiveness of the twin-city area will be strengthened by improved accessibility, new companies and business, better image and a variety in living options.”Risks and ChallengesThe project poses risks in the construction and execution phases as well as economic, political and technological challenges.In its initial phase, the tunnel’s main problems are related to the geology at the proposed exit location in Estonia, as an important source of water supply for the city is located there.Apart from the uncertainty surrounding its funding, the study also warns that "globally, the political risk for the project progress could be a culmination of the crisis between East and West."At a national level, tensions might arise due to the different process and culture surrounding of the decision-making process."The political success of the tunnel project will depend on the wideness of its impact area and how it is combined with the whole transport system of both countries," the study says.These are still early days for any clear decision, but a potential next step for the project would be the foundation of a Finnish-Estonian project organisation followed by a full feasibility study to make it clear when the tunnel is to be expected.According to Hannes Virkus, an adviser at the Estonian ministry of economic affairs, real decisions shouldn't be expected before 2018.* This is a version of an article that first appeared at www.railway-technology.com.
Waking up at 5.30am, spending two hours travelling to the construction site, starting work around 8am — regardless of the weather conditions — finishing the workday at 4pm and travelling back home for two hours, is the routine of construction worker Ben Grant.Grant lives in Bournemouth, but works in London. The 23-year-old turned down a warehouse career to follow one in the construction industry. “I like working in construction, because you can see the progress you are making. At the end of the day you can look back and see what you’ve accomplished, because it’s just right in front of you,” says Grant.Even though working in construction can be personally rewarding, a high demand for workers has been reported by the UK construction industry in recent months and years. “There is definitely a high demand for more construction workers. I am aware that the company we are subcontracted to is needing at least 100 more workers at the moment and I can only imagine that this is a problem throughout lots of [construction] companies,” says Grant.A survey of construction recruitment firms, recently released by the Recruitment & Employment Confederation (REC) — a membership and professional body for the UK recruitment industry — highlighted that demand.The survey also concluded that 69% of the construction recruitment agencies surveyed believe that the shortage of bricklayers, labourers and other tradesmen constitutes the first or second most significant risk to their businesses.Kate Shoesmith, REC’s head of policy, says: “One of the things that comes up time and time again [in the survey] is that in the construction industry there is a high demand [for workers] and some of the roles are really difficult to fill and to find people with the appropriate skills. “They [recruitment agencies] are saying that it is really difficult to find bricklayers, scaffolders and estimators for the temporary construction jobs. If you look at the engineering side, they are talking about high ways engineers and structural engineers. If you look at the permanent jobs, where it’s difficult to find people in construction, they are saying that it’s very difficult to find architects right now.”Bespoke Recruitment Ltd has been supplying construction workers to the sector since 2001 and has been feeling the pressure. “We have a skill shortage at the moment in construction and we are struggling. We have demand for construction workers,” says Simon Noakes, co-founder and director of Bespoke Recruitment Ltd.Meanwhile, the Chartered Institute of Building this week promoted the concept of former servicemen and women from the Armed Forces joining the construction industry, ahead of the UK Armed Forces Day on June 25.The recessionThe UK construction sector has come a long way since the global recession in late 2007, which saw a reduction in construction projects and consequently a reduction in construction jobs across the sector. In recent years, the sector has been picking up the pace — as can be witnessed in London by looking at the skyline and the number of cranes and construction sites active in the city.The latest employment data released by the Office for National Statistics (ONS) corroborates this scenario. According to the ONS, the construction sector was the second biggest job creator in 2015, accounting for 25% of job growth that year. And, construction output has risen 2.5% in April 2016 — the biggest monthly increase since January 2014 —slowing down now only due to the EU Referendum and the uncertainty it brings with it.The industry has a number of jobs to offer, but simply no people to fill them. “There are lots of opportunities in construction at the moment and we cannot fill these roles,” says Noakes.“We have no pipeline of talent coming through the industry, so we don’t see many 18- or 21-year-olds going to college learning to be a plumber or a bricklayer.” Despite the recession starting almost ten years ago, parts of the construction sector are still paying the price of a shortage of workers.Shoesmith at REC says: “The global recession affected the UK market particularly deeply.“There were a number of people working in the industry who, when the jobs stopped coming, [started] thinking about whether they would continue to work as labourers. There were an awful lot of building projects that just stopped and there was no more commissioning of new building projects in the UK. When the jobs started to dry up they left the industry.”Misperception and lack of informationAdding to this, Clive Turner, research manager of NHBC Foundation — the research arm of NHBC, the UK’s leading home warranty and insurance provider — believes that there is still a misperception and lack of information not only about the industry, but also about the jobs it offers. “There is a perception about house building having a bad reputation in terms of what it offers. People don’t see it offering a career progression,” says Turner.“What we fear is that people don’t see the progression opportunities. They would like it to be a worthwhile job, but they are not sure it is, and I think they don’t always see that what you do can be extremely rewarding. “If you don’t realise [that] there is a career path that you can follow you will be forever thinking this could be a dead end job for anybody. There’s nothing worse than that.”A recent study by NHBC Foundation concluded that nearly 50% of parents are not doing enough to encourage their children to pursue a career in the construction industry, specifically in the house-building sector. “[It is] quiet a serious concern and we need to do more to encourage parents to be aware of what house building can offer,” says Turner.“There is a disparity between what house building can offer and what is actually offered to young people through their parents or career advisers. “The issue is the absence of a suitable level of information and guidance on what are a range of very interesting jobs.”Possible solutionsOne way of addressing this issue is attracting and captivating young people into the industry. “We need to think about recruitment and retention strategies, we need to see more investment in things like apprenticeships, that used to be a really golden route for entering the jobs market in construction,” says Shoesmith. “It was a highly credible route. “We need to see more government support for that. We obviously need to think about how we give career advices to young people before they are even thinking about the job options. “Do young people know that there are really good careers to be having in the construction industry? Are they aware of all the opportunities for them?”Other way of engaging young people into the construction sector is offering them a wide range of work experience opportunities while they are still of school age, because — according to Shoesmith — “it’s only by seeing what is like to work in the industry that you can actually visualise yourself there and see whether is something that is right for you”.The Crossrail project has addressed the shortage of skills in the UK construction industry by setting up an academy, where they have trained 20,000 people to develop tunneling and construction skills. They have already had 550 apprentices go through the system.Initiatives such as this can help to encourage workers to join the construction industry — as may the wage rise that has taken place across the sector.The latest employment data released by the ONS shows a 7.5% year-on-year increase in wages in the construction sector.“There are obviously huge rewards there, because the pay is increasing in this sector as the skills supply gets worse,” says Shoesmith.REC’s survey also concluded that some bricklayers are taking home £1,000 ($1,470) a week. Kevin Green, REC’s chief executive, says: “If you work in construction you can expect to be earning £34 a week more than last year, and our data indicates that some employers are increasing pay faster as the competition for skilled workers intensifies.” Expected to attract a wide range of people into the industry, Bespoke Recruitment Ltd is following this trend: through the agency a bricklayer is paid £180–£200 a day and a labourer £8.50–£9 an hour.
A selection of current construction work and studies shows hydropower’s wide range, says Patrick Reynolds. Numerous hydropower and pumped storage projects are in construction or planning across the globe, and International Water Power & Dam Construction (IWP&DC) briefly notes progress and developments on a selection in Asia, Europe, North America and South America, and also the Middle East.A major hydropower scheme that is well advanced is the Ulu Jelai project, in Malaysia. Being constructed by Salini Impregilo, the project involves significant surface and underground works.Both surface and underground works feature in the Foz Tua pumped storage project, in Portugal, and which is also at an advanced stage. The project involves construction of a 108m-high double-curvature arch dam.Developing hydropower where a new dam is not needed, efforts are pushing ahead in the US to exploit existing lock and dams structures, such as the run-of-river projects being undertaken by power company American Municipal Power (AMP) on the Ohio River. The plants under construction include 72MW Smithland.Statkraft may give the go-ahead this year for two run-of-river projects in Chile, following an acquisition in 2015. However, following a recent review of its investment programme it has yet to decide what action it will take.Many further projects are coming, and a few among those include recent awards for consultants MWH Global and ÅF, respectively, in South America, Europe and the Middle East.Malaysia: Ulu JelaiConstruction of the 383MW Ulu Jelai hydropower project, in Malaysia, has been underway since 2011 and is well advanced, including the recent milestone completion of the Susu roller compacted concrete (RCC) dam.Ulu Jelai is being developed by Tenaga Nasional Berhad (TNB) in Pahang state, approximately 200km north of the capital Kuala Lumpur. It is one of five hydro projects being built at present to help stabilise the power grid.The project is located on Bertam River, and involves major dam and tunnel works. The rated net head of the scheme is approximately 360m.Key features of the project include the Susu reservoir on Bertam River, and to which water is conveyed by transfer tunnels from the Lemoi and Telom rivers, running on opposite sides of the main river. Lemoi and Telom are tributaries of Bertam and naturally join the main river downstream of the project location but are being tapped with offtake weirs at higher elevations. The tunnels have lengths of 7.5km and 8.5km, respectively.Water flows from Susu reservoir down a 9.5m-diameter unlined headrace tunnel to the underground powerhouse complex, holding a pair of 191MW Francis turbines. Ulu Jelai is expected to generate approximately 326GWh of electricity annually.Salini Impregilo is main contractor on the scheme, which is nearing completion.The Susu RCC dam is more than 80m-high with a crest length of 512.5m. Its volume is approximately 750,000m3, the contractor said.The volume of other concrete works on the project is approximately 190,000m3. Surface excavations and earth moving has involved more than 3M m3 of material.Underground construction has been performed by both TBM boring and drill and blast excavation. In total, the project has called for excavation of 26km of tunnels and also the powerhouse cavern complex. The TBMs were used to bore 15km of tunnels, and 11km of excavation of undertaken by drill and blast.Salini Impregilo notes that the total underground rock excavation is approximately 800,000m3.
A deteriorating section of the fluming carrying water to Tarraleah power station has been repaired on time and in budget, improving the safety and condition of this important infrastructure. Generating energy from water over the long term requires significant on-going investment in the safety and performance of more than dams and turbines. Water conveyance infrastructure also needs regular attention to keep the water flowing across the many, often rugged, kilometres from storages to power stations."Across a century of hydropower development, Hydro Tasmania has constructed 55 major dams, 30 power stations, and hundreds of kilometres of waterways," said Hydro Tasmania's civil portfolio manager Neil Smith."Many of these assets were world firsts when they were built and continue to provide outstanding service to this day. But, like any valuable infrastructure, our hydroelectricity and water assets require on-going maintenance to perform well into the future."A timely and successful repair of a rapidly deteriorating section of the flume carrying water to Hydro Tasmania's Tarraleah Power Station has greatly improved the safety and condition of this important piece of water conveyance infrastructure, and ensured its reliable service in Tasmania's power system for at least another 50 years.And if that isn't cause enough for celebration, this repair has also been achieved within schedule and budget, using safe and innovative design and construction methods, and carefully considering the flume's heritage values.
What links novelty personalised figurines, prosthetic body parts, components for cars and fighter jets, jewellery, guitars — and now, houses?They’re all on the list of objects that have been created using 3D printing technology. And while some of those projects will probably prove to be passing fads — feel free to take a moment at this stage to Google the inexplicable Japanese trend of printing models of Hollywood actor Keanu Reeves looking sad, if you really must — the use of 3D printing to produce entire buildings is gathering momentum.A few years ago, 3D printing or additive manufacturing (AM) was used in the construction sector mainly to produce construction components and niche parts, such as interior-decorating features, lighting effects and furniture. In recent years construction companies and national governments raised the bar with ambitious projects to 3D-print bigger and bigger structures. The goal was set: 3D print entire buildings. The challenge was laid down and the industry could only wait for the first buildings to rise. And they did. In several countries 3D-printed projects have been initiated, and in some they have now been finished. That is the case in Dubai, where the world’s first 3D-printed office building has recently opened its doors. The 250sq m single-storey building has been built in just 17 days using a 20ft tall 3D printer and a special mix of concrete — fibre-reinforced plastic and glass fibre-reinforced gypsum. The gigantic printer was 120ft long and 40ft wide and ‘worked’ almost alone, as it only needed one staffer to make sure it was functioning properly. The rest of the 18-person construction crew consisted of installers, electricians and mechanical engineers who completed the project for just a mere $140,000 in construction and labour costs, about half price of a comparable structure built using conventional methods. The building is set to have a practical use as the temporary headquarters for the Dubai Future Foundation, becoming home of Dubai’s Museum of the Future next year. The opening follows the launch of the ‘Dubai 3D Printing Strategy’ and the forecast that a quarter of buildings in Dubai will have 3D-printed elements by 2030.
Hydro projects of all stages continue to make Asia a growth sector, says Patrick Reynolds. Among the many hydropower projects in development in Asia, expansions are underway at the Baglihar scheme in India, the Tarbela dam in Pakistan, and Lamtakong Jolabha Vadhana pumped storage plant in Thailand.Also in Pakistan milestone progress has been achieved recently at Neelum Jhelum, and studies are advancing plans for Thakot and other projects in the Indus basin.A range of further supporting studies for hydro projects are underway in Nepal and Bhutan, respectively, and also Vietnam — including Lai Chai where works are advanced. A refurbishment project is in preparation for a key hydro scheme in Tajikistan.Nepal also has a focus on irrigation needs, including a wider examination of flood hazard risk.Himalayas/Central AsiaIndia: Baglihar-II The 450MW Baglihar-II project in Jammu & Kashmir, India, was inaugurated recently by Prime Minister Narendra Modi. Developed on the Chenab River, the project is the second stage of the Baglihar scheme and doubles the installed capacity at the site to 900MW. The Stage I plant was built over 2000-2008. Their joint output is expected to be approximately 4180GWh of electricity annually.Project developer is the Jammu & Kashmir State Power Development Corporation. Lahmeyer International — part of Tractebel Engineering, a division of ENGIE previously GDF Suez — is the Engineer-in-Charge of the Baglihar site, and since 1999 has had engineering responsibilities on both stages of the development.Contractor on both stages is Jaiprakash Associates. E&M supplier on Stage II are Voith Hydro and Andritz Hydro, and for Stage I were Voith Siemens and VATECH, respectively.Both stages are served by a 144.5m-high concrete gravity dam with an integrated overflow spillway. Each stage also features significant underground infrastructure. The intakes to both are located in the bank, immediately upstream of the dam.The stages have parallel diversion tunnels at the dam. The headrace tunnels also run together for most of their distance, and each has a 77m high surge shaft.The underground powerhouses of the two stages, each with 3 x 150MW Francis units, are close together — Stage II complex is located immediately upstream of the Stage I caverns. The cavern complexes are approximately 180m apart.Each powerhouse cavern is 50m high x 24m wide x 121m long; and, the transformer caverns are 24m high x 15m wide x 112m long. The caverns were excavated over 2011-2013.Downstream of each powerhouse complex are further underground works, located before the tailrace tunnels: the underground structures are ‘Collection Galleries’. For Stage I, the collection gallery is a single cavern; for Stage II, the system includes a lower gallery 20.6m high x 14m wide x 95m long, three 14m-wide riser shafts and a gate operating top gallery 9m high x 16m wide x 57m long.The tailrace tunnels are different, too — Stage I is short (130m), high (29m) and flow is free-flowing; Stage II is a 350m-long, 10m-diameter pressurised tunnel.Other projects on the Chenab that Lahmeyer has worked on include Sawalkote, Ratle and Pakal Dul.Separately, in Himachal Pradesh, Lahmeyer recently provided consultancy services for the Thana Plaun project being developed on the Beas River by Himachal Pradesh Power Corporation. The 187MW scheme involves dam works and an underground powerhouse, and is expected to generate about 530GWh annually.Pakistan: Thakot Investigations are underway to prepare a feasibility study for the Thakot hydro scheme being developed on the Indus River by Pakistan's Water & Power Development Authority (WAPDA).Thakot is being developed as a project of at least 2GW, and is located immediately upstream of the existing Tarbela reservoir. It is part of a cascade of large hydro schemes planned to be built on the river, and upstream projects include 2.4GW Patan and 4.5GW Daimer-Basha.Lahmeyer is working with local partners on studies for the three WAPDA projects — Thakot, Patan and Daimer-Basha, respectively.The next project upstream from Thakot in the Indus cascade is Patan, and others being planned include Dasu and Daimler-Basha, which is 315km upstream of Tarbela dam.For the Thakot project, WAPDA is seeking to exploit a head of approximately 180m between Patan and Tarbela. Planning studies for Thakot are investigating options for either a single project or a few created as a small, intermediate cascade, says Lahmeyer. Thakot dam site is at a narrow section of the river, just downstream of Besham.At Tarbela itself, WAPDA is currently constructing the 4th Extension Project at the site to add 1410MW by June 2017 — an earlier deadline to an accelerated programme, announced in January. The extension will increase the installed capacity at Tarbela to 4888MW.Civils works on the 4th Extension Project are being executed by SinoHydro, and the E&M package is being supplied by Voith Hydro. Consultants working on the project are Mott MacDonald and Coyne et Bellier with subconsultants MM Pakistan and ACE Pakistan. The consulting team has also undertaken studies for the 5th Extension project.Tarbela was completed in the 1970s, and generating units have been added in phases up to the early 1990s.An earlier project for Lahmeyer was a feasibility study review for the high-head, 34MW Harpo scheme, on a tributary on the Indus. Separately from Indus developments, WAPDA noted the milestone progress achieved in underground works in February, with a key tunnel breakthrough on the 969MW Neelum Jhelum scheme. The project is to be commissioned over the second half of 2017. Contractor is Chinese consortium CGGC-CMEC. Consultants are Neelum Jhelum Consultants, which is a joint venture of MWH, Norplan, Nespak, ACE and NDC.Tajikistan: Qairokkum rehab ILF is providing consultancy services to national utility Barqi Tojik for the rehabilitation, uprating and safety improvements at Qairokkum hydro plant, in Tajikistan.The 66-year old plant on the Syr-Darya River is to have its capacity increased from 126MW to 174MW, and various E&M and civil engineering packages of works undertaken for the rehabilitation.The project is also to deliver dam safety improvements, the quality of electricity supply, and climate change resilience.ILF will provide services during procurement and construction phases, and commissioning.Funding support for the scheme has been given by the European Bank for Reconstruction and Development (EBRD).The bank also — along with the World Bank and European Investment Bank (EIB) — has given funding support to the related CASA-1000 transmission line project, which will help Tajikistan export hydropower to the Kyrgyz Republic, Pakistan and Afghanistan. Mott MacDonald has also carried out climate resilience studies on Tajikistan's water sector for the Asian Development Bank (ADB).Nepal Consultants Lahmeyer, Total Management Services (TMS), Entura and Manitoba Hydro International (MHI) are working across a number of water studies and projects in Nepal. The different contracts range from flood hazard studies and providing consultancy services to the Nagmati irrigation scheme and development of Tanahu hydro project, respectively.Lahmeyer is working with local partner TMS on flood hazard studies in 25 key river basins — including a focus of mitigation measures in six catchments — for the Ministry of Irrigation. The studies were due for completion in the first quarter of this year.The client division managing the task is the ministry's Water Resources Project Preparation Facility (WRPPF), which has ADB funding support to focus on urgent projects to mitigate both climate change impacts and ensure sustainability of food supply.Separately, the ministry and ADB have commissioned Entura as lead consultant for the initial services of investigations and updating the feasibility study of the Nagmati dam, near Kathmandu.Following consultancy services will include detailed design of the dam and reservoir operation regime, and assistance with procurement for the construction stage of the project to be built in the Bagmati river basin.In hydropower, development services for the 140MW Tanahu hydro project — the country's first large storage reservoir — are being provided by Lahmeyer with the support of MHI.The consultants were appointed to the project last year by the developer, Tanahu Power Ltd, a special project company established by the Nepal Electricity Authority (NEA) to build and operate the scheme.Tanahu is located on the Upper Seti River, and key infrastructure includes a 140m high gravity dam, chute spillway, underground powerhouse and associated tunnels. The reservoir will have a sediment flushing capability to help maintain the active storage volume.Bhutan The World Bank has appointed ÅF — a Swedish engineering and consulting company — to undertake an environmental and sustainability study of the 720MW Mangdechhu hydro project, currently under construction in Bhutan.ÅF is more than half way through the assignment on the Mangdechhu project being built in Trongsa Dzongkhag district in the centre of Bhutan.The run-of-river scheme is designed to operate under a minimum gross head of 344m, and includes significant dam and underground works: a 101.5m high concrete gravity dam, diversion tunnel, 13.5km long headrace, and powerhouse caverns.The consultant is due to report its findings to the bank and Bhutanese authorities before the middle of this year. The work is being conducted in accordance with the Hydropower Sustainability Assessment Protocol, which covers a wide range of areas, including climate change and human rights.The Mangdechhu scheme is being developed by Mangdechhu Hydroelectric Project Authority — a joint venture of the governments of Bhutan and India, the latter providing most of the finance. The project is due for completion in 2018, generating more than 2900GWh/year, and supplying power domestically and to India.In fiscal year 2006-7, India's NHPC entered into an agreement with the Government of Bhutan to prepare a detailed project report of the proposed scheme, then envisaged with a capacity of 672MW. Feasibilities studies for the scheme were supported by Japan and Norway.SE AsiaThailand: Lamtakong Jolabha Vadhana PS, Phase 2 ÅF is supporting the Electricity Generating Authority of Thailand (EGAT) on the extension project to double the capacity of the 500MW Lamtakong Jolabha Vadhana pumped storage plant.The underground plant has two pump-turbines in operation, and was initially commissioned in 2002. The 500MW expansion project at Lamtakong Jolabha Vadhana is due for completion in late 2018.Lamtakong Jolabha Vadhana is located in Nakhon Ratchasima province, was the first underground plant hydro facility in Thailand and remains the principal plant supplying power in the northeast provinces, says Electricity Generating Authority of Thailand (EGAT). Its upper reservoir is on Yai Tieng Mountain, and the powerhouse in 350m underground.Phase 2 of the project will add two further 250MW units, taking the total capacity of the PS plant to 1GW. Work at the plant is also to include installation of two circuits of 95km-long high-voltage transmission lines to connect with the Tha Lan 3 substation, in Saraburi province.ÅF signed a contract with EGAT to provide a range of services while the extension project is executed under by an engineering, procurement and construction (EPC) contractor.The consultant's services include design review, project management, engineering and field services through all stages of execution, including commissioning.Vietnam: Lai Chau HEP ÅF is also active in neighbouring Vietnam, where the consultant most recent began work on the supporting the implementation of the environmental and social action plan for the Lai Chau hydro project.The 1200MW Lai Chau project is under development on the Da River, in Lai Chau province, in the northwest of the country close to the border with China. Construction of the 131m high roller compacted concrete (RCC) dam at Lai Chau was completed in mid-2015.Lai Chau is being development by Electricity of Viet Nam (EVN). ÅF has already been working on the project as sub-consultant to Power Engineering Consulting JSC No1 (PECC1), a former subsidiary of EVN, and the assignment continues to 2017.ÅF was awarded the environmental and social action plan contract by Son La Hydropower Management Board (SLaMB). The board and ÅF worked together previously on the 2400MW Son La project, on the same river and also featuring a major, 138m high RCC dam. Son La was completed in early 2011.The environmental and social action plan contract for Lai Chau is funded by KfW, and ÅF is already working on another contract in Vietnam funded by the German development bank — gap analysis on environmental aspects of a smart grid transmission project. ÅF says the contract is similar to the objectives at Lai Chau by checking environmental and social due diligence, in this case for 6 x 220kV transmission lines.
As always at Bauma, the skyline was filled with the latest crane models – here are some of the highlights.