Friday, September 20, 2019
The Oresund Fixed Link Project Construction Essay
The Oresund Fixed Link Project Construction Essay The Oresund Fixed Link was a project initiated in 1991 by the Swedish and Danish governments and completed and opened in July 2000. The bridge, island and tunnel combination connects the two metropolitan areas of the Oresund region, Copenhagen, Denmark and Malmo, Sweden. The Link consists of the Oresund Bridge, a two-level (one for traffic, one for rail) pylon-supported structure, the Oresund Tunnel, a 4km-long tunnel, and the Peberholm Artificial Island which would transfer the traffic from the submerged tunnel to the bridge. It was undertaken in a cooperative effort between the Swedish and Danish governments whereby they would each form half of the owner company (ÃËresundsbro Konsortiet) in 1992, which in turn was responsible for financing, planning, designing, building and eventually operating the link (Oresundsbro Konsortiet, 2009). We will attempt to demonstrate that the Oresund Fixed Link is one of the more successful mega-projects. à ¢Ã¢â ¬Ã ¦ has argued that mega-projects such as the analogous Channel Tunnel, Sydney Opera house or Millennium Dome are subject to cost and time overruns and quality shortfalls. The factors behind those deficiencies include a politicization of the tendering and project proposal process, the legacy complex which can besiege governmental spending and the inefficient management of projects on a public level. The experience of the Oresund Fixed Link, whilst not without short-comings, is recognized as being a project that in terms of the QCD paradigm was satisfactorily managed and far removed from the problematic projects of its time. To this end, in May 2003, the Oresund Bridge won the International Association for Bridge and Structural Engineering (IABSE) Outstanding Structure Award, recognizing not only its design and construction but more importantly in our context, its adhere nce to the proposed deliverables. Project Phases: Concept Identifying the need and opportunity: The need for a link between Denmark and Sweden which crossed the Oresund sound was not a novel one in 1991. In fact, the region had been the subject of territorial disputes between the nations dating back to the 1600s and had fallen under ownership of both nations at various times (Oresundsbro Konsortiet, 2009). Lack of political will and unstable economic conditions had prevented the Link from being properly canvassed before the late 1980s. There were a range of economic, infrastructural and political factors which created a need for a bridge between the two nations in the early 1990s. Firstly, although Sweden was not member of the European Union (then EEC) at that time, its attention had been directed to accession during the European recession of the late 1980s (Oresundsbro Konsortiet, 2009). Denmark had already acceded to the EEC in 1986. The increased focus on European integration meant that links, allowing the movement of goods and labour in particular would be required. Furthermore, Denmark as part of continental Europe, could act as a gateway to Sweden and Finland in the north. European integration was thus a driving factor behind the Link and the potential benefits it could have in bringing the two nations and indeed Europe and Scandinavia closer together. A more practical consideration in determining the demand for the Link was that of offering an alternative to the ferry-based transport service that was in place at the time. The ferry service, with irregular timetabling and being subject to good weather conditions, could be allowed to operate more efficiently if there were an alternative link which allowed both trade, leisure and commuter traffic(Oresundsbro Konsortiet, 2009). The need for the link between Denmark and Sweden to increase efficiency and integration provided an opportunity to create a single Oresund metropolitan area. The conglomeration of the two separate Copenhagen and Malmo markets would allow for a common housing and labour market and increased commercial and educational opportunities. As Denmark and Sweden became more involved in the European process, and Europe became more integrated and markets more competitive, it was apparent that the Oresund region could become a leading metropolis and hub if connected. The opportunity was also present for both nations as the Scandinavian banking crisis brought both nations into recessions and paved the way for stimulatory spending on infrastructure and other projects. Initial Risk Assessment: An immediate risk at the time of conception was posed by the economic conditions brought about by the Scandinavian banking crisis (IMF, 2002). Although this presented an opportunity, the economic climate at that time was far from certain and that uncertainty could have strong implications on financing interest rates and resource and supply costs from overseas in the light of exchange rate fluctuations. The division of the stake in the consortium overseeing company between Swedish and Danish governments allowed the mitigation of risk by reducing cost of borrowing (Oresundsbro Konsortiet, 2009). Another obvious risk faced by the project initiators was that being a mega-project, handing over responsibility for design and construction to just one company places strong burden on that firm. In order to mitigate this risk, the initiators separated the project into three parts the Tunnel, the Bridge and the artificial island linking the two so as to hopefully improve delay, cost and quality. Whilst this reduces the risk of default and delay on the contract, it does pose an additional risk of non-communication or worse still non-compliance between the separate components of the design. The risk that the Link would damage the environment was very much in the consciousness of the project initiators from the outset (Oresundsbro Konsortiet, 2009). This may be because Denmark and Sweden are traditionally active in the conservation sphere, place emphasis on sustainable development and have the worlds tightest controls on offshore construction. Or it could be as a result of strong lobby-group pressure which raised concerns regarding the potential environmental impacts of the Link (American University, 2005). Whichever it may be, the initiators committed, with some spurring on, to the creation of a project which was as much environmentally friendly as possible. The potential bad publicity and financial losses from environmental damage was something which the initiators wanted to avoid. Alternative Approaches: There were few alternative approaches to the Oresund Link project, given the set parameters of joining Sweden and Denmark and creating value (Oresundsbro Konsortiet, 2009). The opportunity to link Malmo and Copenhagen metropolitan areas implied long-term, quantifiable value creation. One alternative may have been the Danish city Elsinore and Swedish Helsingborg, which are closer than Copenhagen and Malmo across the Sound, however the initiators believed that more benefit would be derived by joining two large cities and offering a connection near Copenhagen Airport to benefit air travelers (Oresundsbro Konsortiet, 2009). Alternatives to the 3-part project were also few. This is because the land under the Sound was not even. As such, it would not be possible to build a bridge which spanned the whole sound nor a tunnel without incurring extra cost. Scope Management Project Definition: The project offered the following opportunities for the project initiators: Create stronger trade and investment links between Denmark and Sweden as two nations Create further integration between continental Europe and Scandinavia Provide an alternative transport mechanism crossing the Sound so as to increase the efficiency of trade and business and leisure travel Develop the Malmo-Copenhagen metropolitan area into one of the leading hubs in Europe Offer a symbolic and impressive structure to the two nations The overall objective, by which the success of the project might be gauged, was, as stipulated in the treaty, to construct a Link which was ecologically motivate, technically possible and financially reasonable to prevent any detrimental effects to the environment. The scope of the project would include: Tender for the design of the Link Construction of the Link Construction and development of the surrounding areas Time Management: Unlike other mega-projects such as sites for the Olympic Games, the time was not especially short for the Oresund link. The initiators evidently wanted to keep it as short as possible, to capitalize on the growing links in Europe and to provide the service to consumers as quickly as possible. Additionally, by minimizing time, the two states could attempt to reduce cost overrun. The initial time span was set at 10 years from the signing of the treaty in 1991 (Oresundsbro Konsortiet, 2009). Quality Management: Quality was seen as perhaps the most important parameter to be satisfied in the project, above cost and time. The consortium was charged with ensuring that the quality of the Link met all European safety and structural standards (Eurocodes) (Kjaer, 2001). In addition it was stipulated that in terms of safety, The Link should be no more dangerous than using the national roads or railroads (Kjaer, 2001). The Link also had to improve transport time across the Sound. A very important parameter set for the designers and constructors was to limit the environmental impact of the Link. Cost Management: The budget for the construction cost was set at 13.9billon DKK or 2.4billion USD in 1990 prices (Kjaer, 2001). The consortium was charged with the financing, budgeting and planning. Since the Consortium was owned by the Swedish and Danish governments the financial resources, within reason, were not as constraining a factor as the quality objective. Furthermore, the fact that project was financed outside of state budgets by the consortium meant it was not subject to restrictions on resource allocation by the respective governments. Project Phases: Development Design Selection of the Link As we mentioned in the precedent chapter, after the Swedish and Danish government set up a 50:50 joint venture ÃËresundsbro Konsortiet in 1992, the company then organized a design competition for the bridge in early 1993. The competition took over for 2 months; the result came out in July that year with two entirely different bridge concepts chosen by the owner for further discussion before the final decision taken: -Group ASOs two-level, mainly steel, structure, with the motorway placed above the railway, ASO Group was initiated by Arup(specialized in structural engineering and who has carried out the Sydney Opera House and the Pompidou Center in Paris) and formed as well with SETEC (France), Gimsing Madsen and ISC (both Denmark), Tyrà ©ns (Sweden), and with Georg Rotne (Denmark) as architect to the Group; A single-level, mainly concrete, bridge, with the motorway between the two railway tracks, developed by the ÃËLC consortium. They both had a cable-stayed main span. Following the awards, as to make an easier and wiser decision for the selection of designer, a continuous scheme designs were prepared to confirm the concepts developed during the short competition period, along with the consultants worked with the Owner to develop the project and get ready for the construction phase. Thus the further design process can be defined as: Consultations with authorities to obtain their approval establish a design basis and a contract strategy set up administrative procedures develop the design in some detail prepare tender documents Whereas it turned out that ASOs strong and robust design concept was safely carried through this whole design process with only very few and insignificant modifications. Tender documents were issued for proposals from both semi-final winners- ASO and ÃËLC in December 1994, for two contracts for each: one for the approach spans, and the other for the cable-stayed spans. The tenders were returned in June 1995, and after the evaluation, the single contract was signed with Sundlink Contractors in November 1995 for the whole of ASO Groups two-level design for the bridge. The other two main contracts one for Dredging and Reclamation and one for the Tunnel had been let during the summer, and several coast-to-coast contracts were let during 1997-98 for the railway and for various installations such as SCADA / traffic control, communications, toll system and the terminal area. Design and Construct Contract Strategy The Owner had early decided to let the contracts as design-and-construct contracts, but modified so as to safeguard the conceptual designs that had been prepared. In essence the contracts were for detailed design and construction. As we have emphasized that such a Design Construction contract allowed avoiding any possible incompatibilities caused by different designer and constructor so that Owner were able to minimize the risks in this aspect. According to the contract documents, we can clearly identify the principles behind the Owners contract strategy which included: à ¢Ã¢â ¬Ã ¢ Detailed design-and-build à ¢Ã¢â ¬Ã ¢ A 100 years service life à ¢Ã¢â ¬Ã ¢ Application of well-known technology à ¢Ã¢â ¬Ã ¢ Control and documentation of quality à ¢Ã¢â ¬Ã ¢ Division of risks attributable to ground and weather conditions and obtaining permits. The contract documents were written expressly for the project, and defined the Owners requirements regarding function, aesthetics, safety, and environmental protection. Everything required to fulfill those requirements was included in the Contractors scope of work, with only specified duties on the Owner. The Contractor was responsible for the detailed design as well as for the construction of the work, and was given considerable freedom regarding the means and methods of doing his work which is also a factor key for the success of this mega project. In essence the Owner specified what the Contractor should achieve, and the Contractor determined how to achieve it. The Contractor was responsible for supervising his own work and for providing documentary evidence that he had done so and that the quality of the work he had done was of the standard required by the Contract. The Owner monitored the Contractors performance but this did not relieve the Contractor of his obligations under the contract. This contract strategy led to several special documents being included in the tender documents issued to the bidders, in particular definition drawings, an illustrative design, reference conditions, and quality system requirements. The definition drawings described the design features, geometry, and materials that should be retained in the Contractors design, and at the same time defined the limits within which he had the freedom to choose. The illustrative design showed the bidders, for information only, a comprehensive design that fulfilled the Owners requirements. Risk Assessment So as to minimize the possible risks could ever take place during the construction phase, the Owner assigned ASO as the developer of the Operational Risk Assessment of the entire ÃËresund link. But since ASO itself was involved in it, the process would benefit from the contribution of external reviewers, so Professor Tendrup Pedersen from the Danish Technical University was appointed to review the marine aspects and Arup to review the remainder. As far as we know, it is the first time such a comprehensive risk analysis has been undertaken during the design of a major fixed link. A fully quantified risk assessment of the human safety and traffic delay risks was carried out for a comprehensive list of hazards: à ¢Ã¢â ¬Ã ¢ fire à ¢Ã¢â ¬Ã ¢ explosion à ¢Ã¢â ¬Ã ¢ train collisions and derailments à ¢Ã¢â ¬Ã ¢ road accidents à ¢Ã¢â ¬Ã ¢ ship collisions and groundings à ¢Ã¢â ¬Ã ¢ aircraft collisions à ¢Ã¢â ¬Ã ¢ toxic spillages à ¢Ã¢â ¬Ã ¢ environmental loads beyond design basis. Initially, the assessment attempted solely to identity the risks beyond those of typical stretches of motorway and railway on mainland Denmark or Sweden. However, it soon became obvious that this approach could be improved by considering total risks and being able to compare the Links risks with international risk acceptance criteria. We found out that the risk assessment was carried out along with the design process and influenced several design decisions, the most significant being the size of the bridge pier foundations to withstand ship impact, the realignment of the main shipping channel to reduce groundings, and the provision of passive fire protection on the tunnel walls and ceilings.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment