| Summary: | 碩士 === 國立臺灣大學 === 土木工程學研究所 === 101 === Seismic assessments of current existing reinforced concrete bridge piers require adequate analytical models that could predict the behavior of the RC (Reinforced Concrete) member on the elastic range, inelastic range, and up to post-failure range. Current available analytical models such as the plastic hinge model for pushover analysis could not capture the cyclic loading history, cumulative damage, and pinching effect on the reinforced concrete member. The analytical models using hysteretic rules could overcome the weakness of pushover analysis. Although most of the available hysteretic rules models could approximate the nonlinear pier column behavior, they require nonphysical damage parameters to be defined.
To improve the analytical model, general analytical models that only require material and geometric properties were proposed. The models were developed with the intention to represent the common hysteresis behavior of RC bridge pier subjected to static cyclic loading including pinching effect and strength degradation after the onset of failure. Three common failures observed in existing RC bridge piers were chosen for modeling study: flexure failure with buckling on longitudinal reinforcement, flexure shear failure, and pure shear failure. Each failure mode was proposed with different spring model. The hysteretic loop comparison shows that the constructed analytical models could predict the nonlinear degrading behavior with sufficient accuracy.
In addition to static analyses, dynamic analyses were also carried out and compared with pseudodynamic test result of RC bridge piers. The analytical model results closely follow the test results in term of displacement time history. Using the proposed analytical model, parametric study using far field, near fault and long duration ground motion was also conducted.
The constructed analytical models provide a base for modeling the RC bridge piers behavior for the engineering community. The models serve as a stepping stone for further research in the future.
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