Long-term analysis of timber-concrete composite bridges

The design of timber-concrete composite bridges is complicated due to time-dependent phenomenon like creep, shrinkage of concrete and effects of the varying temperature and moisture content. Unfortunately, at the moment, Eurocodes include very limited guidelines for designing such bridges. Existing guidelines and methods, time-dependent material models and effects of the environmental variations were studied for the long-term analysis. Based on the findings, a simulation tool for timber-concrete composite beam accounting the time-dependent phenomena was developed. Temperature and moisture content histories of the bridge components based on the existing weather data. The tool was used to simulate the effects over the service life in two cases; a bridge built using un-shored or shored construction method. In overall, wide agreement between the simulation and the approximate model was found.