Fiber-Based Seismic Damage and Collapse Assessment of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Index

The research objective of this project is to propose high-fidelity fiber-based nonlinear finite element models (FEM) to simulate the damage development process of reinforced concrete (RC) bridge piers under earthquake loadings considering various combined damage mechanisms as well as to assess seismic performance of RC bridge piers. In California, earthquakes have repeatedly demonstrated the seismic vulnerability of existing bridges and the urgent need for seismic retrofit and bridge maintenance. The ability to predict damage states for the design of RC bridge piers is fundamental to the performance-based seismic design (PBSD) of bridges. Damage indices and ductility coefficients will be used to quantify damage level of structures caused by an earthquake, which play a vital role in retrofit decision-making and disaster-planning in earthquake regions. To identify RC single-column pier-supported bridges with structural deficiencies for seismic retrofit and maintenance, the innovative damage indices together with ductility-based methodologies will be proposed for seismic damage and collapse assessment of RC single-column pier-supported bridges. A section damage index will be proposed based on the material damage indices definition and bridge performance assessment. A set of tested RC bridge piers tested under different uniaxial quasi-static loading regimes will be adopted to verify the reliability of the proposed finite element and damage models. The significance of the proposed models is to advance and improve the accuracy in the predictions of the nonlinear behaviors of RC single-column pier-supported bridges as well as offer insight into the structural system responses under near-fault and far-fault ground motions.