Skorpa L.,Norwegian Public Roads Administration
Procedia Engineering | Year: 2010
The Norwegian coastline is rugged with long fjords, and exposed to wind and waves from the North Sea. The fjords represent barriers to crossing traffic, and thus also to industrial growth in the coastal regions. Because of the many ferry connections in coastal regions, the Norwegian Public Roads Administration has always been searching for new ways to cross the fjords by fixed connections. During the last years limits have been stretched with regard to the use of slender suspension bridges as well as long and deep sub sea rock tunnels. However, there are still many ferry connections left. These are the most extreme fjord crossings, where existing bridge building technology has to be developed further, and in addition, new knowledge and experience from offshore technology turns out to be of great importance. To develop new alternative fjord crossing methods, the Norwegian Public Roads Administration, Western Region, has organized a conceptual feasibility study of how to cross the wide and extremely deep Sognefjord. The experience from this study will be of great value to other fjord crossing projects as well. In addition, the study may be of interest to projects in scenic inland lake areas and urban waterfront areas. The feasibility study focuses on crossing alternatives based on the use of water as a bearing element of the bridge structures. It includes different crossing methods such as suspension bridges, floating bridges, submerged floating tunnels (SFT), and combinations of these. The results from these studies, with focus on the use of submerged floating tunnels, as seen from the owners point of view are discussed in the paper. The use of new technology raises questions with regard to safety of the structures as well as to the traffic. The study also gives important knowledge about where the different alternative crossing methods can meet local conditions on different crossing sites with regard to width and depth of the fjord, exposure to wind, sea waves, and ships traffic. © 2010 Elsevier Ltd. All rights reserved.
Ostlid H.,Norwegian Public Roads Administration
Procedia Engineering | Year: 2010
When is a Submerged Floating Tunnel competitive?The various elements in transport systems are most often selected on the basis of the lowest price for the alternatives being viaducts, bridges or tunnels or some combinations of these. The submerged floating tunnel will therefore have to compete with well known structures and therefore have a disadvantage since no submerged floating tunnel has yet to be built. A future owner is then faced with a risk not easily estimated on one hand, on the other hand this new alternative may have certain attractive features especially when environmental considerations become important. This paper presents these various advantages and also points out some obvious disadvantages with this new and challenging structure. A great step forward would be if a submerged floating tunnel were built somewhere. The proposed structure here in China would certainly generate a lot of interest and I suggest the involved parties should prepare for a large number of visitors. © 2010 Published by Elsevier Ltd.
Odeck J.,Norwegian University of Science and Technology |
Odeck J.,Molde University College |
Johansen K.,Norwegian Public Roads Administration
Transportation Research Part A: Policy and Practice | Year: 2016
We estimate the elasticities of fuel and travel demand with respect to fuel prices and income in the case of Norway. Furthermore, we derive the direct rebound effects that explain the degree to which a fuel price increase is "offset" in the form of greater fuel use and/or travel due to improvements in vehicle fuel efficiency. For this purpose, we use and compare two alternative econometric approaches: the error correction model (ECM) and the dynamic model. Our initial assumption is that one should not be indifferent with respect to the approach used to derive elasticities. The data used are for the period 1980-2011. Our results indicate the following: (1) the dynamic model fits the data better than the ECM model does; (2) the estimated elasticities of fuel demand with respect to price and income are -0.26 and 0.06 in the short run and -0.36 and 0.09 in the long run. For travel demand, the respective elasticities are -0.11 and 0.06 in the short run and -0.24 and 0.13 in the long run, implying inelastic demands for fuel and travel demand; and (3) rebound effects indicate that 0.26% and 0.06% of fuel savings as a result of fuel price increase will be offset in the form of more fuel use in the short run and in the long run, respectively, if fuel efficiency increases by 1%. Our policy recommendations are that policies should not be indifferent to the methods used to derive elasticities. We contend that it is crucial to seriously consider rebound effects in policy making because basic elasticity estimates exaggerate the impact of fuel price increases. © 2015 Elsevier Ltd.
Hoien A.H.,Norwegian Public Roads Administration |
Nilsen B.,Norwegian University of Science and Technology
Rock Mechanics and Rock Engineering | Year: 2014
The Løren road tunnel is a part of a major project at Ring road 3 in Oslo, Norway. The rock part of the tunnel is 915 m long and has two tubes with three lanes and breakdown lanes. Strict water ingress restriction was specified and continuous rock mass grouting was, therefore, carried out for the entire tunnel, which was excavated in folded Cambro-Silurian shales intruded by numerous dykes. This paper describes the rock mass grouting that was carried out for the Løren tunnel. Particular emphasis is placed on discussing grout consumption and the challenges that were encountered when passing under a distinct rock depression. Measurement while drilling (MWD) technology was used for this project, and, in this paper, the relationships between the drill parameter interpretation (DPI) factors water and fracturing are examined in relation to grout volumes. A lowering of the groundwater table was experienced during excavation under the rock depression, but the groundwater was nearly re-established after completion of the main construction work. A planned 80-m watertight concrete lining was not required to be built due to the excellent results from grouting in the rock depression area. A relationship was found between leakages mapped in the tunnel and the DPI water factor, indicating that water is actually present where the DPI water factor shows water in the rock. It is concluded that, for the Løren tunnel, careful planning and high-quality execution of the rock mass grouting made the measured water ingress meet the restrictions. For future projects, the DPI water factor may be used to give a better understanding of the material in which the rock mass grouting is performed and may also be used to reduce the time spent and volumes used when grouting. © 2013 The Author(s).
Lindgard J.,Sintef |
Thomas M.D.A.,University of New Brunswick |
Sellevold E.J.,Norwegian University of Science and Technology |
Pedersen B.,Norwegian Public Roads Administration |
And 4 more authors.
Cement and Concrete Research | Year: 2013
Whether or not concrete prism tests developed for assessment of alkali-silica reactivity of aggregates might be suitable for general ASR performance testing of concrete has been evaluated. This paper discusses how variations in specimen pre-treatment, ASR exposure conditions and prism size influence the rate and amount of alkali leaching and prism expansion, together with a discussion of consequences for ASR test procedures. Furthermore, results from some complementary tests are included. Generally, a remarkably high proportion of the in-mixed alkalis were leached out of the concrete prisms during the ASR exposure. For prisms exposed to 60 C, the rate and amount of alkali leaching is the main controlling factor for the prism expansion. For less permeable concretes exposed to 38 C, lack of internal moisture and lower rate of diffusion contributes to reduce the rate and extent of ASR expansion (reported in a separate paper). © 2013 Elsevier Ltd.