Denna dimensioneringshandbok är ett resultat av forskningsprojektet RFS-PR-04120 INTAB “Economic and Durable Design of Composite Bridges with Integreral Abutments” (Feldmann, et al., 2010) och det efterföljande disseminationsprojektet RFS – P2 - 08065 INTAB+ “Economic and Durable Design of Composite Bridges with Integreral Abutments” (Feldmann, et al., 2012), som varit delfinansierat av EU:s forskningsfond ”Research Fund for Coal and Steel” (RFCS) samt Svenska Byggbranschens Utvecklingsfond (SBUF). Inom forskningsprojektet har väsentlig kunskap inhämtats för att skapa möjlighet att öka konkurrenskraften hos samverkansbroar med integrerade landfästen. Denna kunskap har inarbetats i denna dimensioneringshandbok, vars engelska version har presenterats vid ett antal internationella seminarier och workshops.

One of the most commonly discussed problems regarding bridges with integral abutments is the influence of longitudinal elongation of the superstructure as a result of seasonal temperature variations. A bridge built with integral abutments is often supported by a row of piles made of steel or concrete. The longitudinal elongation of the superstructure induces a displacement and a rotation at the top of the pile, which in turn may cause strains that exceeds the yield strain. Such seasonal variations may lead to low-cyclic fatigue failure in the pile. Therefore, it is of great interest to investigate the amplitude of these strains, as well as the general behaviour of the bridge. In 2005, the European R&D project, INTAB (RFSR-CT-2005-00041, "Economic and Durable Design of Bridges with Integral Abutments, 2005-2008") was started. Within the INTAB project a composite bridge was built and monitored in Northern Sweden.

In the international project "Sustainable Bridges", one of the deliverables is a design guide for strengthening of bridges. This paper gives the reader a first look into this guidelinewhich can be found at the projects website: www.sustainablebridges.net

The scope of this project is to perform Life Cycle Cost Analysis (LCCA) on different types of bridges, in order to learn which is most cost-efficient in a particular situation. A second scope is to study the impact of different cost items on the whole Life Cycle Cost. The work is performed to enable optimal strategic decisions regarding future investments.Beam and Slab Bridges, Slab Bridges and Slab Frame Bridges are analyzed. The bridges are located in the north of Sweden, in the regions of Norrbotten and Västerbotten. All bridges have a total length of around 20 m, which is the most common length in Sweden and in Europe. Furthermore, the analysis includes Timber and Soil-Steel bridges in order to understand the prospects for this types of bridges in Sweden. The analysis does not focus on a particular bridge but, based on information from some Swedish producers, it studies different scenarios.The data collection covers initial investments, maintenance, repair and rehabilitation (MR&R) costs, user and demolition costs.

Preliminary results obtained from short term test-loading are used to illustrate possibilities of FEM used to calibrate complex interaction characteristics between a pile and soil in a bridge with integral abutments. The measurements are obtained during the winter season on the bridge over Leduån, in Northern Sweden. The bridge is built in 2006 and used for long term monitoring within the international project INTAB supported by RFCS. The main objective of the on-going research project is to propose recommendations for rational analysis and design of bridges with integral abutments.

Emneord: Bridges, Design

Bridge engineers very often face economic restrictions on their designs in addition to technical requirements. Those requirements are related not only to initial construction costs but also the cost to maintain the bridge condition at the level required by the bridge administration. In standard bridge structures, expansion joints are one of the most expensive components to maintain. In this regard, jointless bridges have major advantages. Integral bridges are built without joints, they span from one abutment to the other abutment, possibly over intermediate piers, without any joints in the deck. The absence of joints and bearings results in savings in initial costs and reduce maintenance efforts. Apart from economical benefits, the reduction of maintenance leads to less disturbance of the traffic over the bridge and thus to smaller environmental and social impacts. In this paper a case study is presented with the purpose of making a comparative life cycle analysis between an integral composite bridge and a concrete bridge with expansion joints. The result of this life cycle analysis will enhance the advantages of the former solution in regard of economical and environmental aspects.