The move towards performance-based seismic design and retrofit of highway bridges has created an urgent need for innovations in analytical modeling and computer simulation of the seismic performance of bridges. Due to the complexity of structural performance of bridges during strong earthquakes and the high degree of nonlinearity in system response, computer simulations have to be verified with experimental data to establish their reliability. The purpose of this study is to investigate nonlinear models of nonlinear bridge response to seismic loads. These models will be based on measured responses of shake table tests of model bridges undertaken at the University of Nevada at Reno. A specific subtask in the numerical simulation part of the study is to be undertaken in collaboration with researchers from the University of Ljublijana (ULJ), Slovenia. The research will be focused on the analytical methodologies appropriate for multi-span viaducts having continuous deck and piers of different heights. Such structures have characteristics that complicate their response and introduce important higher modes. The research will greatly improve the understanding of bridge response to collapse under seismic loads and provide new analytic models for evaluating bridge designs.
Bridge systems are one of the most complex structural systems to model for earthquake performance because of the number of different components (foundations, substructures, abutments, hinges, and superstructure). Verified simulation is necessary in bridge design so that engineers can assess the response of different designs, understand the sensitivity to uncertain parameters, and provide information on the expected performance. The results of the research findings on simulation will be distilled into comprehensive guidelines to be used by bridge designers and researchers. The educational benefits of the proposed international collaboration will be important. Graduate students from both countries will closely interact with researchers from other countries. These students will be trained in earthquake engineering research and design and will be exposed to international views and perspectives. The exchange of ideas and data with Slovenian experts in this field will enable U.S. participants to advance their own work and develop tools that can be integrated in education and practice. The training of skilled individuals with an understanding of international issues will enhance the manpower in the US scientific work force and will improve the labor pool for more advanced design and research work in the global market.
