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Both performance- and method-based specifications were applied on the Øresund Link Project. For example, a performance specification was used for the amount of contamination from dredged materials being placed back into the sea. A 5 percent requirement was specified; that is, no more than 5 percent returned to the sea. Performance-based specifications were introduced by the management team on this project, but use was somewhat limited in favor of well-established method specifications. By law, warranties are required in the specifications, including 1 year on pavements, and 10 years on overall performance and on electrical/mechanical works. Again, warranty performance is expected to be established through a partnering effort and by resolution and agreement between the contractor and management team. The management team intends to provide performance quality primarily through construction quality control rather than longterm performance measures and risk assignment to the contractor. A very small performance bond was required, approximately DKr1 million (~US$150,000), for the tender and 15 percent for the contract execution. Implementation Regarding pre-engineering requirements provided to the contractor, in Denmark, the owner normally provides a detailed geotechnical report for the project and 90 percent of the design. For example, the locations of foundations are indicated. With regard to geotechnical design requirements, foundations must currently be designed in accordance with the Danish Foundation Code. Eurocode 7, however, was required for foundation design on the Øresund Link Project. Functional criteria are primarily provided in the contract to define the desired quality for what is being built. For example, a structure must be able to tolerate a certain amount of settlement, and the foundation soil must not settle more than that value. As the owner performs a thorough geotechnical bid-basis subsurface exploration, the contractor only performs a post-bid exploration for verification purposes, if required. In case of disputes over unanticipated conditions on the Øresund Link Project, a dispute review board would be used. For quality control on design-build projects, the contractor develops and submits a quality-control plan for the owner’s approval, after the award. The qualifications for the laboratory (-ies) performing the tests (including verification testing of geotechnical materials) are specified by the contractor in the quality-control plan, and the contractor must demonstrate that a quality lab is being used. Once the quality-control plan is in place and approved by the owner, the contractor must show evidence that the completed design or constructed element meets the quality requirements or functional criteria indicated in the contract. Quality-assurance reviews are performed at intervals outlined in the contract, and the contractor does not get paid until the quality control records are submitted and approved. In fact, the quality-control reports must be attached to the invoice, and the owner must accept quality provided by the contractor before the contractor is paid. Performance CHAPTER 3 The most significant obstacle that the Danes have encountered in trying to implement designbuild contracting has been environmental concern. Permits are especially difficult to obtain and require a certain amount of design ahead of time. For example, on the Øresund Link Project, the number of piers on the Swedish side had to be known before permits could be 23
24 CHAPTER 3 obtained. For this reason, an illustrative design was completed by the owner, prior to obtaining bids. Overall, the Danes feel that design-build has worked well. It fosters a partnership between industry and the owner and helps them operate more efficiently. From a contractor’s perspective, it works best on a large and unique project with significant engineering content. A standard project does not allow enough innovation for design-build to be practical. Both time and cost savings have been realized on projects involving innovation, but standard projects, such as a two-lane bridge, do not present opportunities for innovation and, therefore, no opportunities for cost or time savings. GEOTECHNICAL PRACTICE There have been numerous recent geotechnical developments in Scandinavia, several of which have arisen from the Storebælt and the Øresund Link Projects. Advances in groundimprovement technologies include: • The Danes developed a new method, known as “MOSES,” Method of Obtaining Safety by Emptying Storebælt. MOSES is a dewatering technique used to construct tunnels under the sea bottom using deep wells into the sea bottom for temporary reduction of high-pore pressures. • A new method for ground freezing, also developed by the Danes, was used on the Storebælt Link Project in an innovative way to stabilize the water-bearing strata for tunneling purposes. • A good QA/QC procedure for controlling the construction of lime columns and shallow soil mixing has been developed by the Norwegians. • In Sweden, some improvements have been made in monitoring methods for making deep excavations to keep track of deformations that occur as a result of the excavation process. This method is currently in use on a big project in Stockholm. • A coastal stabilization method has been developed in Denmark that uses nature’s own forces in a positive way to counteract the destructive forces that usually result in beach erosion and damage. The awesome power of the sea waves is used to arrive at ecofriendly and invisible coastal stabilization. The patented technique, called “Beach Management System,” is used to control the development of a sandy beach or where erosion is threatening agricultural or infrastructure assets. The system consists of buried drain pipes that are connected to collector wells and pumping stations. By lowering the ground water level below the coastline level, downwards percolation of water from the wave runup is introduced, whereby the soil is stabilized in the same way as by a standard dewatering operation for an excavation. This reduces the backwash on the beach face and limits the erosion process while deposing more sand on the beach. The concept has also been applied successfully at four sites in the United States by Moretrench American Cooperation. With regard to in situ testing of geotechnical materials, recent developments have included the following:
Page 1 and 2: GEOTECHNICAL ENGINEERING PRACTICES
Page 3 and 4: 1. Report No. FHWA-PL-99-013 4. Tit
Page 5 and 6: iv FHWA INTERNATIONAL TECHNOLOGY EX
Page 7 and 8: vi 4. COUNTRY SUMMARY: GERMANY ....
Page 9 and 10: viii ABBREVIATIONS AASHTO American
Page 11 and 12: x the derivation because of differe
Page 13 and 14: xii 4. Institute reliability-based
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Page 17 and 18: 2 CHAPTER 1 PURPOSE The primary obj
Page 19 and 20: 4 CHAPTER 1 PREVIEW OF REPORT The p
Page 21 and 22: 6 CHAPTER 2 • The designers did n
Page 23 and 24: 8 CHAPTER 2 INNOVATIVE CONTRACTING
Page 25 and 26: 10 CHAPTER 2 The MTO does not curre
Page 27 and 28: 12 CHAPTER 2 innovation and have no
Page 30 and 31: CHAPTER 3 COUNTRY SUMMARY: DENMARK
Page 32 and 33: Part 1 of Eurocode 7, which deals w
Page 34 and 35: Case A is related mainly to the sta
Page 36 and 37: Soil friction 1.2 Soil cohesion (fo
Page 40: • Development by the Danes of a c
Page 43 and 44: 28 CHAPTER 4 • Sliding and overal
Page 45 and 46: 30 CHAPTER 4 Existing DIN standards
Page 47 and 48: 32 CHAPTER 4 INNOVATIVE CONTRACTING
Page 49 and 50: 34 CHAPTER 4 design. Quality contro
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Page 54 and 55: factors for safety in load, resista
Page 56 and 57: Implementation Most structural desi
Page 58 and 59: GEOTECHNICAL PRACTICE Several innov
Page 60 and 61: LESSONS LEARNED: LRFD CHAPTER 6 MAJ
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Page 64 and 65: CHAPTER 6 geotechnical subsurface a
Page 66 and 67: In all of the countries visited, th
Page 68 and 69: CHAPTER 7 CONCLUSIONS AND RECOMMEND
Page 70: • Prepare a list of do’s and do
Page 73 and 74: 58 1.7 What process do you use to m
Page 75 and 76: 60 2.13 What problems have been enc
Page 77 and 78: 62 Gerabek, Peter, Chief, Geotechni
Page 79 and 80: 64 GERMANY Bauer, K., Head of the D
Page 82 and 83: BIBLIOGRAPHY (Reference Materials D
Page 84 and 85: —— . Terms of Engagement for Co
Page 86 and 87: GERMAN REFERENCES Berghaus, K., “
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Routes and Roads, “Routes de Fran
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Office Of International Programs FH
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