Modeling and analysis of a prestressed girder bridgeprior to diagnostic load testing

Progressive deterioration is a problem that affects road infrastructure, especially bridges. This requires the development of methods to determine its influence on structural behavior, one of them being load testing. Within load testing, finite element analysis (FEA) models are used as part of the preparation process. This study focused on the modeling and analysis of the static response of the bridge over the Lili River in Cali, Colombia, a prestressed girder bridge programmed to undergo a diagnostic load test. A linear FEA model was created, and variations were applied to the stiffness of diaphragms and elastomeric bearings. The analysis included obtaining the critical position for the design vehicles, the transversal distribution of stresses, and the influence of the variation parameters in the structural response. Results showed that the critical responses were with loads close to the exterior girders and that the variation of parameters did not significantly influence the structural response of the bridge. Girder Distribution Factors (GDF) were contrasted with previous research, finding similarities in shape and value. Finally, an instrumentation plan was proposed. The findings show how linear FEA models provide relevant information regarding the critical position, the distribution of stresses and the expected response under design loads.