NONLINEAR FINITE-ELEMENT ANALYSIS OF DETERIORATED RC SLAB BRIDGE

Applications of nonlinear finite element analysis (NLFEA) to complete structures have been Limited, The study reported in this paper examine d the reliability of NLFEA to assess strength and stiffness of a three -span reinforced concrete slab bridge that was loaded to failure in th e field. The researchers at the University of Cincinnati and Delft Uni versity of Technology, in The Netherlands, conducted preliminary analy ses that were then compared to the measured responses. These analyses indicate a significant influence of tensile behavior of concrete in th e postcracking range, and the level of slab membrane force that is dir ectly affected by the assumed horizontal support conditions at the sla b-abutment connections. Reasonable correlation of the measured respons es was possible by removing the horizontal restraints at the slab-abut ment connections. However, such models do not simulate the observed be havior at the abutments. The shear keys at the slab-abutment connectio ns would not permit free horizontal movements, yet the slab can rotate about the shear keys. The resulting rotation would reduce the membran e force that can be developed. An improved model incorporating this be havior produced better results than the original model assuming full h orizontal restraints at the abutments.