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News Article | May 18, 2017
Site: www.enr.com

For ENR’s Top 400 Contractors, the construction market is going strong and predictions of a leveling off or even a decline have been premature. While many in the industry now believe the market will remain healthy for the foreseeable future, large contractors in the big-ticket international oil-and-gas and mining markets did take another hit in 2016—although most are weathering that storm. Last year was a strong one for the Top 400, which  generated a record $366.41 billion in contracting revenue, an increase of 6.5% from 2015’s $344.14 billion. However, the real story is on the domestic side. Contracting revenue from U.S. projects rose a healthy 9.7%, to $322.83 billion, on top of a 9.5% rise in domestic revenue last year. On the other hand, non-U.S. contracting revenue plunged 12.5%, to $43.58 billion, in 2016, with the major declines noted in projects in the minerals-and-mining, petroleum and power sectors. Bechtel continued its Top 400 dominance, ranking No. 1 for the 19th consecutive year. However, the oil price slump and the soft minerals-and-mining sector had a significant impact on its markets. Despite this, Bechtel’s contracting revenue was up in 2016. “When the collapse in oil prices happened, people in the petroleum industry expected them to bounce back in a year. It didn’t happen. Now people are wondering if they will ever bounce back to where they were,” says Jack Futcher, named Bechtel chief operating officer last year. It is a different story in the U.S., Futcher says. Cheap feedstock from domestic gas and oil extraction has spurred development of petrochemical facilities and gas-fired power plants. He notes, for example, that Bechtel has designed and will soon break ground on Shell Chemical Appalachia petrochemicals complex, including an ethylene cracker and a polyethylene derivatives unit, near Pittsburgh. The complex will use low-cost ethane from shale gas producers in the Marcellus and Utica basins to produce 1.6 million annual tons of polyethylene. Many contractors in the oil-and-gas sector agree that oil prices will remain depressed as new extraction technologies have allowed more oil and gas reserves to be accessed. “We see oil prices lower for longer, with a slight uptick … to around $55-$60 per barrel,” says Graham Hill, executive vice president of KBR. He also says the center of production has shifted. “The U.S. is becoming the advantage feedstock nation of the world—the ‘new Saudi Arabia’ in downstream and the ‘new Qatar’ in midstream liquefied natural gas.” In the international market, Futcher also notes that low oil prices have propelled oil-producing nations in the Middle East to move away from reliance on oil revenue to maintain their economic strength. Cheap energy prices have spurred some countries in the region to move into aluminum smelting, in which Bechtel has significant construction expertise. Unlike design firms, there is less consolidation among contractors. The few contractor acquisitions of note in the past year include Burns & McDonnell’s buy of Appleton, Wis.-based industrial contractor AZCO Inc. in December. AZCO ranked No. 82 on last year’s ENR Top 600. “We did not have experience in direct-hire contracting that AZCO now provides us with,” says Ray Kowalik, Burns & McDonnell CEO. The biggest move on the Top 400 was the acquisition of U.S.-based MWH Global by Stantec, enabling the Canadian parent’s first appearance on the Top 400. Stantec CEO Bob Gomes says the move was spurred by customer demands for a more integrated approach to construction. It also gives Stantec a greater geographic range in the international market, he says. “AECOM has committed $250 million to help provide project financing through AECOM Capital.” —Dan McQuade, President for construction, AECOM AECOM, another firm known principally for design that broke into the contracting ranks a few years ago with its acquisitions of Tishman Construction, Hunt Construction and URS, now ranks No. 5 on the Top 400. “We are now fully integrated and are able to provide the full package of design-build and design-build-finance delivery,” says Dan McQuade, AECOM construction president. “Last year was one of tremendous growth on the contracting side,” McQuade says. He notes that the AECOM Tishman group is working on or has just completed seven buildings of at least $1 billion in size, and that the Hunt group is working on football stadiums for the Atlanta Falcons and Los Angeles Rams. The firm also won the job to decommission the San Onofre Nuclear Generating Station in Pendleton, Calif. A significant development has been the growth of many international firms in the U.S. market to take advantage of growing infrastructure investment. These include Spanish contractors Dragados, OHL and Ferrovial, France’s Colas, Italy’s Salini-Impregilo with its recent acquisition of Connecticut-based Lane Industries and China’s China Construction America, all of which are becoming major U.S. market players. “The competition from these companies is fierce, as they are showing up with big balance sheets,” says Richard Cavallaro, CEO of Skanska USA. “Ten years ago, we were one of the few foreign-owned contractors, but we had been here for decades.” There is a considerable concern among contractors about the ability of clients to obtain financing for projects. The U.S. Federal Reserve has begun raising interest rates at a modest pace, having an impact on the cost of borrowing. Further, banks are becoming a little edgy about how much of their lending portfolios is devoted to real estate. “One of the big reasons for that is that the banks don’t want to start lending when the policy that will dictate the market is still unknown, so it’s tough to get construction loans,” says Jeff Hoopes, CEO of Swinerton. He says banks are looking at other markets and different products to invest in, and that’s impacted business across the board. The reluctance of banks to commit to more real estate lending, particularly in the residential market, has caused developers to seek other means of financing. “Developers across the board tell us they are seeking out second- and third-tier lenders for financing arrangements. The exception appears to be the healthcare sector, which traditionally finances projects internally,” says Scott Thompson, senior vice president of Batson-Cook Co. “While some projects have been delayed because of tightening financing markets, other financial players—including real estate funds established by developers—have stepped up to pick up the slack,” adds Ken Colao, president of CNY Group. Cavallaro says the ability to arrange, or even participate, in project financing is a key to get many jobs off the ground. “Skanska has a major financing group that can help make things happen.” McQuade says that AECOM now is a major player in the move toward contractors assisting, or even contributing to, project financing. “AECOM has committed $250 million to help provide project financing through AECOM Capital.” McQuade says that about $1 billion in current AECOM projects are the result of AECOM Capital either helping to find financing, or actually contributing to the financial package. Donald Trump’s election as president last year has been a key market development, with many industry participants expecting a more pro-business climate, leading to greater opportunities. “In 2016, I thought we were in the late innings of the construction boom, but since November, a lot of people in the industry are more bullish that the market will continue to be strong,” says McQuade. He believes some market energy may be resulting from a lull in the run-up to the election, but he says peers now are more optimistic. However, many contractors are taking a wait-and-see attitude about the new administration, saying it will take from six to 18 months for the full impact of new policies to affect the industry. “I think the Trump effect will manifest itself more clearly in 2018. We have some concerns about immigration and foreign trade policies, as they relate to construction labor and materials pricing,” says Paul D. Little, CEO of Alston Construction. There are signs that pro-growth policies may benefit the industry. Bechtel’s Futcher says cutting corporate taxes may result in repatriating foreign profits of U.S. corporations in the form of capital investments here. And, “if the right policies are enacted, we hope to see an increase in foreign direct investment in the U.S.,” says Stephen Gray, CEO of Gray Construction. Shaun Yancey, president of U.S. operations at PCL Construction Enterprises, sums up the general attitude among contractors: “There is quite a bit of rhetoric around the construction industry, but we are still waiting on the administration. Although there is optimism about the future of our industry, there is quite a bit of uncertainty at this moment.” Many contractors in specific markets see potential headwinds as a result of the election. On the power side, firms in the renewables market want to know what will happen with investment tax credits. “We don’t know if Trump is going to basically eliminate those, and we’re still not sure if they’re going to get phased out in 2023 like they’re set up to, or get shut off next year,” says Hoopes of Swinerton. With some customer reluctance in the market, he is seeing a little bit of a slowdown in the solar market as people wait to see what’s going happen with Trump and his policies. The healthcare market also has suffered over the past few years as construction clients in the sector had to adjust to the impact of the 2010 Affordable Care Act. But several firms see a market pickup. “Right now, we are seeing lots of healthcare projects on the horizon … [mostly] medium-sized renovation and upgrade projects,” says Dan Starr, president of GE Johnson Construction Co. He says this upsurge is a carryover from the last recession when many hospitals held back on improving systems to better understand the Affordable Care Act and its impact on their business. Structure Tone also is benefitting from this uptick. “Our LF Driscoll team has been building healthcare facilities in the Philadelphia area and in New Jersey for decades, and we’ve now extended that expertise into the New York City metropolitan area,” says Bob Mullen, Structure Tone CEO. The markets in the technology and related sectors continue to go full-bore. “We are seeing an even stronger demand than last year from our advanced technology customers, who are building data-center and mission-critical projects to support the insatiable demand for new content,” says Mike Ford, a member of DPR’s management committee. Further, e-commerce is having a major impact on the retail market. Many firms bemoan that the market for retail stores and shopping malls is suffering as more people turn to online buying. On the other hand, “we see the industrial warehouse and distribution market remaining very strong for the near term. Vacancy rates are lower, and rents are slightly higher in most markets,” says Little of Alston Construction. “Similarly we see very healthy conditions in our food and beverage and healthcare segments.” Despite a strong market, many contractors complain that competition continues to be fierce. Some firms say that many contractors fear a decline in the market and are bidding on anything to build backlog to get them through future lean times. This fierce competition has caused margins to stagnate, despite the amount of work available. “It would be assumed that general contractor fees would have risen as firms have become busier, but that’s not necessarily what we’re seeing,” says Dave Bangasser, CEO of Opus Design Build. “Subcontractor margins have rebounded better than those of general contractors.” William H. Goodrich, CEO of LeChase Construction Services, adds that “a number of jobs are being awarded as if construction is purely a commodity—on price alone. But it may be a disservice to all contractors to accept that low bids—to the point of a deficit—are a strategy for being competitive. We have more to offer.” Part of the problem about depressed margins stems from owner expectations in the wake of the industry downturn in 2008. Many general contractors chased work at reduced margins to maintain market share. As a result, many clients became accustomed to lower construction costs. “This effect, coupled with high demand for new construction and the current labor shortage, has led some clients to believe that GCs are simply charging more for their services, when in many cases margins remain compressed,” says Mark Yanik, vice president of Leopardo Cos. Inc. Another recession hangover is the expectation by owners that contractors will accept more burden in contract terms. “A precedent was set in the recession for owners to include [contract clauses such as] no waiver of consequential damages, broad indemnity and other onerous contract terms, and this aggressive stance on contracting has not changed as the market rebounded,” says Tim Steigerwald, Messer Construction Co. senior vice president. Risk-shifting also is a major bone of contention among contractors. “A trend we are seeing more often is owners pushing more risk onto the contractor without the ability to manage those risks as we see fit, and contract terms that are less favorable,” says PCL’s Yancey. This trend has resulted in a rise in insurance premiums and deductibles, an increase in alternate procurement methods and a hike in regulations related to public works, adds Charles J. Montalbano, president of China Construction America-Civil. “The last few years it was a buyer’s market, where owners were able to push a lot of risk down on us, and we are beginning to pay for that,” says Cavallaro of Skanska USA. But he says that contractors in the current market are more willing and able to push back. “We push, they pull, but it won’t be as easy for owners to get everything they want now.” General contractors’ relationship with subcontractors has improved over the years, as the advancement of alternate delivery models for projects has forced both groups to work more as a team. “The days of contractors telling subs ‘Do what I say’ are over,” says McQuade of AECOM. However, in a strong market, contractors have begun to pay more attention both to the stability and the availability of subcontractors. McQuade says subs are getting stretched, and contractors must be clear on the scope of responsibilities of subs to make sure each under­stands what is expected and whether it has the resources and staff to complete the job. “We are in a day and age where information flow is by the second, but decision-making has not kept up. We are just developing technology to provide visual modeling to help customers make their decisions faster.” —Pat A. Di Filippo, Executive Vice President, Turner Construction Pat A. Di Filippo, executive vice president of Turner Construction, says the financial health of subcontractors is paramount to a successful project. “That is why we have instituted a program to pay invoices from subs within a few days of approval, rather than the normal 30-45 days,” he says, adding that this helps subcontractor cash flow and maintains good relations with firms. Subcontractors are the first ones to run into workforce shortages, particularly in the trades. So some contractors are employing new methods of packaging work to make sure subcontractors are able to perform. “We have seen shortages of labor and staff and we simply augment these trades by carving specific areas of work out of their contracts and awarding this work to additional contractors. On occasion, we may have as many as three contractors working on one trade,” says Colao of CNY Group. Shortages also have led to GCs taking a more active role in the construction process. For example, Turner Construction has begun self-performing concrete work in Boston, Seattle and selected markets in Florida, and occasionally drywall as well. “We are not looking to displace subcontractors, but on some jobs there is a need for special expertise that we can supply internally, rather than subbing it out,” says Di Filippo. Some major self-perform contractors have already addressed the problem of staffing. “Each market we are in has a different trajectory, so we have diversified,” says Futcher of Bechtel. He says that all staff use the same tools and processes, regardless of what market they are working in, making it easy for the company to move people from one type of work to another without worrying about retraining staffers in new procedures. “We have a global resource base of engineers, project managers and other professionals to draw on.” The construction industry has always been slow to adopt new methods and technology, but new advancements in design and communications technology have become a must for most large contractors. Building information modeling and communications technology have become the ante for major firms just to get in the game. Many contractors are venturing into new advanced technologies to improve productivity. For example, sensor technology is a relatively new method that is helping advance the speed of construction. “We are using concrete sensors that get tied to the rebar and buried when the concrete is poured, which in turn provides live drying and curing data directly to our superintendents’ phones, enabling us to make more informed decisions on flooring, roofing, schedules and protection from adverse weather conditions,” Mullen of Structure Tone points out. Site logistics modeling also enables contractors to engage owners on safety discussions, showing the swing radius of a tower crane and locations of laydown areas, traffic relocations and entrance protection. “These are the details owners care about beyond construction, and the 3D printed model builds upon what they can see in the virtual model,” says Steigerwald. Steigerwald also notes that subcontractors and craft workers appreciate site logistics modeling because it showcases complicated geometry, uncovers slab and beam details and depicts tie-in complexities that may otherwise be hard to see virtually. According to Steigerwald, “it’s a great tool for conceptualization and spurring strategic conversations and we’re using it in our owner, coordination and subcontractor meetings with great success.” As the Internet of Things makes its way into every industry, it also is gaining a place in design-build. “The idea of tracking each jobsite’s equipment, workers, milestones and more in one place will improve safety and efficiency, as well as potentially impact the bottom line,” says Gray of Gray Construction. While for some contractors, the information flow is a godsend, others worry that data flow isn’t the problem. “We are in a day and age where information flow is by the second, but decision-making has not kept up. We are just developing technology to provide visual modeling to help customers make their decisions faster,” says Di Filippo. Many contractors agree that virtual reality will speed decision-making. “Virtual reality on a couple of our biggest projects has proven to be very helpful for clients, enabling them to make quicker decisions and increasing their revenue potential before construction is completed,” says Leonard W. Martling, CEO of The Weitz Co.

News Article | May 8, 2017
Site: www.enr.com

Noting their contributions to "the power of the purse" for their employers, women in construction are pushing for parity in compensation, which continues to lag behind that of male peers. Despite numerous studies that show the business value of diverse management and professional teams, a gender-based wage gap still dogs women in the business world, said Carey Smith, president of the federal business unit of Parsons Corp. She made those comments to nearly 400 attendees at ENR's Groundbreaking Women in Construction conference, held May 2-3 in San Francisco. According to Smith, the gender pay gap in construction—with women earning 93¢ for every male dollar—is narrower  than the business average of 82¢ per dollar, "but it's not where we need to be." Smith noted the "amazing statistic" that companies diversified by gender and ethnicity outperform peers by 15% and 35%, respectively, citing research by consultant McKinsey.  "According to the study, womens' equality could add $12 trillion to global economic growth," she told attendees at the event, which is co-sponsored by law firm Peckar & Abramson. A panel of mixed-gender professionals outlined examples of how the "diversity dividend" works in their companies. Lisa Mingoia, corporate counsel at Skanska, said the diversity of its presentation team was a factor in its win of a key construction role on the multibillion-dollar renovation of LaGuardia Airport in New York City, set for completion in 2021. "Having a female executive is the single most important way to drive organizational change," said Laura Abrahamson, AECOM senior vice president and associate general counsel, adding that 45% of the giant AE's staff is female and that women make up 43% of its leadership. Jon Michael Pardo, chief human resource officer at Spain-based contractor Dragados, echoed that contention, noting the diversity strength in its team that successfully competed for construction of a new Chesapeake Bay tunnel. "Europeans have a better model for women in executive roles," he claimed. "In the U.S., we're getting there." Even so, presenters noted evidence of pay gaps in industry sectors. A 2015 study of 2,200 male and female structural engineers revealed a $52,000 gap at the principal level, despite faster advancement of women at lower levels, said Angie Sommer, an associate at ZFA Structural Engineers who co-chaired the survey project, which also looked at practitioner engagement. She said a more detailed study of the compensation gap results will be conducted this year but noted the difficulty of finding competitive compensation data. "It's always been a taboo subject," she told attendees. Priya Kapila, compensation practice leader at industry management consultant FMI, noted the need for "objective measures" such as a company-wide pay equity analysis, and a look at issues related to "comparable worth" of job roles. She also pointed to trends that show disparities resulting from different gender-based negotiating approaches and management aspirations, emphasizing that "recognizing high performers" is critical. Pointing to the Obama administration push to level the compensation playing field through order and regulation, Kellie McElhaney, a consultant and professor in the University of California, Berkeley business school who has studied gender workplace trends, noted changes to come in the Trump government. The president, in late March, revoked a 2014 Obama order that required wage transparency for workers of federal contractors and barred forced arbitration clauses in sexual-harassment settlements. "I have lost faith in the government taking this on," she said, although noting that activist investors and even municipal governments are stepping up to help "de-bias" corporate processes. Parsons Corp. executive Smith said the administration promise of a huge infrastructure program would boost oportunities for women project leaders and business owners in construction. But Smith noted the funding battles that will delay it well into 2018 and other market growth impacts from "trade crises" and labor shortages. For now, Smith called on industry CEOs to "take personal responsibility to drive diversity" in recruiting and retention through efforts such as targeted project assignments, mandated leadership training for diverse candidates and creation of affinity groups "as long as they don't become social organizations."

De La Paz Cobos E.,Ayuntamiento de Madrid | Alcaniz P.J.R.,MBA | Mazo C.S.O.,Catedratico de Ingenieria del Terreno | Gracian F.T.,Dragados
Revista de Obras Publicas | Year: 2013

The article describes the design and construction of the Arroyofresno Stormwater Deposit (the largest of its kind in Europe) and the associated pipework, a 7.40 m diameter tunnel built by EPB TBM. A description is given of the design criteria as well as the soil treatment required for the passing of the pipeline through a river, alongside various installations (in quaternary soils) and below motorways, as well as those necessary to connect the tunnel to the service wells.

Moreno-Navarro F.,University of Granada | Sol-Sanchez M.,University of Granada | Rubio-Gamez M.C.,University of Granada | Segarra-Martinez M.,Dragados
Construction and Building Materials | Year: 2014

The high stiffness provided by high modulus asphalt mixes significantly decreases the loads transmitted by the traffic to the road foundation whilst at the same time increases their resistance against plastic deformations. Thus, the use of these types of mixtures can be an effective solution in road construction, due to the fact that they can reduce the thickness of the pavement, saving economic and material resources. Nevertheless, in some cases this high stiffness constitutes a drawback because it could reduce the fatigue resistance offered by these materials, leading to a premature appearance of cracks in the pavement, which decreases its service life. Due to this fact, the use of high modulus asphalt mixes is limited, especially in cold climates. In order to solve this problem, this research has been focused on the improvement of the mechanical performance of high modulus asphalt mixtures through the use of additives (crumb rubber and acrylic fibers), which could increase their fatigue resistance by maintaining the stiffness required. Different tests have been carried out under different temperatures for the mixtures assessment. The results obtained have shown that the incorporation of these additives could lead to a better mechanical behavior of high modulus asphalt mixes, and thus it could improve their performance. © 2014 Elsevier Ltd. All rights reserved.

Fernandez E.,Dragados | Sauer G.,Dr Sauer Corporation
Proceedings - Rapid Excavation and Tunneling Conference | Year: 2013

Tunneling is one of the industry's solutions to improve our environment and consequently Quality of Life. Putting infrastructures and services underground definitely contributes to a more pleasant urban surface. But how to minimize its long-term construction impact and the "high risk/cost" myth? The authors are trying to identify preconceptions in this particular industry and offering more reliable approaches in terms of cost and schedule based on an overall control mechanism.

Vazquez M.,DRAGADOS | Negro V.,Technical University of Madrid | Lopez J.S.,Technical University of Madrid | Monso J.L.,Institute Hidrodinamica Aplicada INHA
Coasts, Marine Structures and Breakwaters 2013: From Sea to Shore - Meeting the Challenges of the Sea | Year: 2014

This paper presents a novel type of caisson as an integrating element in a new concept of vertical breakwater. The solution combines the advantages of cylindrical geometry with stepped wave energy dissipation, which results in a reduction of maximum wave forces, loads transmitted to foundations and a reduction in crest level in comparison with a conventional vertical breakwater. Also, substantially less materials are used. Whilst the system is complex and depends on multiple geometric, hydraulic, construction and economic variables, this article centres on its hydrodynamic aspects and summarises the most important results of a reduced model testing programme with regular wave action in the first instance, as undertaken to validate the solution in a general fashion.

Fernandez E.,Dragados SA | Magro J.L.,Dragados | Sanz A.,Dragados
Proceedings - Rapid Excavation and Tunneling Conference | Year: 2011

The WSDOT has decided to replace the old Alaskan Way Viaduct on the SR99 for a single bore tunnel able to allocate two lanes on each direction. In accordance with the ground conditions existing on Seattle a pressurized TBM is the right choice. But, the required 57.4′ on excavation diameter goes by far, beyond the existing TBM's and will require the application of the newest technologies on its development. To succeed on this bid a careful and documented technical approach was made, evaluating first the two options between slurry and EPB to excavate the tunnel, followed by the selection of the most effective and proved systems and devices, sometimes duplicated, in order to build the perfect machine for the biggest TBM tunnel ever built, till now. Not only the TBM, but also the impact of the new urban tunnel on the surroundings must be deeply considered during the bid stage in order to estimate the cost and schedule of the ground treatments required to minimize the volume loss and consequently to progress with the excavation in the safest way for all the parties (see Figure 1).

Acerete A.,Acciona | Ayala J.,Acciona | Pidal G.M.,Dragados | Peset L.,Dragados
Structural Engineering International: Journal of the International Association for Bridge and Structural Engineering (IABSE) | Year: 2014

The bridge over the Beauharnois Canal (BHC) is the main structure of the Nouvelle Autoroute 30 project, with a total length of 2551 m. It crosses the BHC and the Saint Laurent Seaway (SLS). This paper describes the development of the design and construction process of the Beauharnois Bridge carried out by a leading construction company in Montreal. It describes the construction procedures carried out to achieve the works in a schedule severely limited by the technical clauses of the contract and winter conditions. This paper emphasizes the different prefabrication systems employed in the construction of the bridge and the incremental launching technique used to erect the steel box-girders of the east part over the BHC and the SLS. The bridge superstructure is divided into two parts: the east part, formed by a closed composite structure with a steel box-girder spanning over 82 m, and the west part, designed with a concrete deck composed of five concrete prefabricated beams spanning a typical length of 45 m. The east part, with a length of 1456 m, was designed with no expansion joints. This side of the deck includes the main span of 150 m and was entirely assembled at the east abutment and erected in place using the incremental launching technique.

Segarra Martinez M.J.,Dragados
Revista de Obras Publicas | Year: 2014

The article describes the particular characteristics of the construction industry with regards to the development of R&D&l activities and the introduction of innovation in the market, when taken from the perspective of the Dragados construction company and, by extension, that of possibly most other large building contractors. A description is given of the context in which these activities are earned in the construction industry and the means by which large contractors approach the problems entailed in the management of R&D&l activities. The article provides a brief summary of certain initiatives that ensure or help ensure that innovation in construction reaches the market to the widest extent possible and concludes with a number of examples of R&D&l activities earned out at Dragados.

Fernandez E.,DRAGADOS | Sanz A.,DRAGADOS
Underground - The Way to the Future: Proceedings of the World Tunnel Congress, WTC 2013 | Year: 2013

The replacement of the old Alaskan Way Viaduct on the SR99 for a single bore tunnel able to allocate two lanes on each direction is the right way to improve the quality of life of Seattle's citizens. For that purpose, an EPB 17.5 m diameter has been selected to excavate the tunnel which is expected to start on spring 2013. The Japanese manufacturer Hitachi Zosen is building the machine which is fitted with proven technologies able to deal with the most varied geologies expected along the alignment. A free air intervention to revise and repair the cutting tools is the most innovative solution on western tunnels despite it has being applied in Japan for more than 12 years. Also robotized segment erector is the logical approach on these large size TBM's. But the Seattle solution can be exported to other cities to solve similar problems and must go together with new TBM developments. The paper describes the latest technologies applied in Seattle and revises alternatives for road and multipurpose tunnels. © 2013 Taylor & Francis Group.

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