| Summary: | 碩士 === 中原大學 === 土木工程研究所 === 104 === In most analyses and designs, bridge columns are assumed to be rigidly connected to the foundation. In reality, bridge columns, however, are buried into the ground with different foundations. Soil confinements provide limited stiffness which could elongate the natural period of the bridge and magnify the lateral displacements. The effect of soil–structure interaction on the seismic assessment of bridges is discussed in this study. Nonlinear static pushover analyses and dynamic time history analyses of single column bent bridges are performed to investigate the accuracy of the pushover analyses. The finite element bridge model incorporates soil-structure interactions through the use of equivalent soil springs and damping. In addition, parametric study is carried out to investigate the effects of soil types and buried depth of piles on the seismic assessments for bridges. Finally, distributed plastic hinges are adopted in piles to study the nonlinear deformation for piles due to the scouring of bridges. Numerical results demonstrate that the results from distributed plastic hinges with modified flexural stiffness coincided well with those from fiber elements in static pushover analyses. In addition, the scouring effects have significant effects on the seismic capacity for scoured bridges in soft soils.
|
|---|
