Nonlinear and Time Dependent Analysis of a Concrete Bridge Suffering from Alkali-Silica Reaction: A Case Study of the Elgeseter Bridge in Trondheim.

Abstract

This thesis reports a case study of the Elgeseter Bridge in Trondheim, which is known to suffer from Alkali-Silica reaction. The main aim is to provide more accurate predictions of the response and capacity of the bridge deck, beams and columns under loading according to håndbok 238 'Bruklassifisering', Norwegian Standards NS 3473 and due to ASR reaction which occurs in this construction. The objective is to form a basis for how ASR mechanisms determined through linear and nonlinear analysis can be used when assessing existing bridges. Concrete expansion due this reaction, the consequences and structural effects are presented. Changes due, to concrete cracking and reinforcement yielding are studied through finite element analyses of this bridge. Recommendations for nonlinear analysis of reinforced concrete slabs with shell and beam elements are established and verified with TNO Diana and SOFiSTiC software. Results from linear and non-linear analysis are verified by comparison with reports. Calculations showed lack of sufficient capacity to shear force and strengthen of the structure is necessary. What is more, this study describes how to use available nowadays methods to prevent the development of ASR reaction in this bridge. Finding relatively accurate solution requires selecting the appropriate methods, the best fitting methods have been considered and have been recommended.