Development of a reliability model for performance analysis of bridges. A case study in Costa Rica

Abstract

In 2013, as part of the e-bridge research project developed by the Institute of Technology of Costa Rica (TEC), a series of non-destructive loading tests were performed in a bridge located over the Purires River, San Isidro de El Guarco, Cartago using a Wireless Sensor Network (RIDS) to collect strain data. The research project intends, among other objectives, to develop a reliability model to assess the structural performance of bridges and providing key output variables to estimate reliability parameters such as failure probability, survival probability and reliability index. The latter information would be important to support a decision making system in terms of a bridge maintenance program.

In this paper, the results obtained using three static non-destructive loads over the Purires Bridge are discussed. Statistical techniques such as goodness of fit tests and Monte Carlo simulation were used to calculate critical structural and reliability indicators. Two of the static tests passed the international references in terms of reliability index; however, one of the statics loads (Case I) failed the analysis reporting a failure probability of 0.047 with a low reliability index of 1.667. It is worthwhile to mention that the same bridge suffered a moderate failure in a critical beam which would help to validate the methodologies and tools used in this project.