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The edge beams of reinforced concrete bridges with de-icing salts sprayed experience extensive corrosion damage. The average service life of edge beams needing replacement in Sweden has been reported as only 45 years, causing great economic loss to both owners and users. Hence, finding a durable solution for edge beams would benefit society. Hybrid reinforced concrete structures, produced by adding a low-to-moderate fibre content into traditional reinforced concrete, can effectively limit the service crack width and improve resistance to chloride-induced corrosion damage. In this paper, different alternatives of hybrid and traditional reinforced edge beams were designed for a case study. The service life of the alternatives was compared by conducting chloride diffusion calculations and by applying a corrosion-induced cracking model. The economic and environmental (indicated by greenhouse gas emissions) benefits of using hybrid reinforced edge beams were assessed by life-cycle cost analysis and life-cycle assessment. The results showed that the service life of edge beams made of hybrid reinforced concrete can be prolonged by over 58%, thereby enabling a significant reduction in the total life-cycle costs and annual total greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

This study assesses glulam and reinforced concrete (RC) beams in a multi-storey building in Gävle in Sweden. StruSoft FEM-Design software is used to conduct the current study. First, the building having the RC beams is modelled, analysed, and designed. Utilisation ratio, stress, weight, reaction force, stability, and deflection of the building are examined. It is concluded that the building can function well with RC beams. Then, the RC beams are replaced with glulam beams and the building is again analysed. It is revealed that larger cross-sections are needed for the replaced glulam beams in most of the spans compared with the RC beams in order for them to have acceptable results from the utilisation ratio viewpoint. However, for large spans of 8 m, a timber column is used in the mid-span for all the storeys as a strengthening alternative so that a shorter span for these glulam beams can be adopted which leads to acceptable results. Stresses of the RC and glulam beams are also evaluated. The building having the glulam beams is 23.79 % lighter than the building having the RC beams. The maximum reaction force of the building having the glulam beams is obtained 24.27 % lower than the building having the RC beams. Stability and deflection of the building in both cases are discussed as well. [ABSTRACT FROM AUTHOR]

The results obtained when performing a load test to failure of an existing structure are valuable when assessing calculation models, updating finite element models, and investigating the true structural behavior. In this paper a destructive testing and monitoring of a railway bridge in Örnsköldsvik, Sweden is presented. In this particular test the shear capacity of the concrete girders was of primary interest. However, for any reasonable placement of the load (a line load placed transverse to the track direction) a bending failure would occur. This problem was solved by strengthening for flexure using carbon fiber reinforced polymer (CFRP) rectangular rods epoxy bonded in sawed up slots, e.g., near surface mounted reinforcement. The strengthening was very successful and resulted in a desired shear failure when the bridge was loaded to failure. The load-carrying capacity in bending for the unstrengthened and strengthened bridge as well as the shear capacity was predicted with Monte Carlo simulations. The particular calculation presented showed that there was a 25% probability of a bending failure instead of a shear failure. Monitoring showed that the strengthening reduced the strain in the tensile steel reinforcement by approximately 10%, and increased the height of the compressed zone by 100 mm. When the shear failure occurred, the utilization of the compression concrete and CFRP rods were 100 and 87.5%, respectively. This indicates that a bending failure indeed was about to occur, even though the final failure was in shear. [ABSTRACT FROM AUTHOR]

The new Svinesund Bridge is an arch motorway bridge on the border separating Norway and Sweden. The arch is a single, centrally located concrete structure with a span of 247.3 m, which is believed to be the longest span for a single free-standing concrete arch in the world. The bridge decks consist of two steel orthotropic boxes, one on each side of the arch and connected by cross beams. The total length of the bridge is 704 m between abutments. The design is the winning concept of an international competition. The bridge was opened to traffic in 2005, and received the fib Award for Outstanding Structures, Special Mention, in 2006. [ABSTRACT FROM AUTHOR]

Since reinforced concrete (RC) buildings have long service life, cutout openings are generally needed in their load-bearing walls as a sustainable solution in order to meet new requirements of their users. However, the cutout openings decrease the load-bearing capacity of the walls, which may result in the failure of the buildings. In this paper, we investigate the possibility of making a door opening in a load-bearing RC wall of an existing building in Gävle in Sweden. The wall studied in the current paper rests on two individual supports at its two ends; thus, it is considered as a deep beam. However, it is called an examined wall (EW) here. The StruSoft FEM-Design software is used in this study to model, analyze, and design the building based on the Eurocodes and Swedish national annex. The potential need for the EW to be strengthened when the cutout opening is made is also evaluated. It is concluded that strengthening the EW with cutout opening is needed. Different strengthening solutions are proposed for the EW. Moreover, the situation of the EW with the solutions is assessed with regard to the utilization ratio, deflection, and weight. Consequently, it is demonstrated that the proposed strengthening solutions function well for the EW. [ABSTRACT FROM AUTHOR]