Seismic Behavior of RC Structures considering the Interaction between Soil and Foundation

考虑土与地基相互作用的RC结构抗震性能

基本信息

批准号：
10650447
负责人：
MUTSUYOSHI Hiroshi
金额：
$ 2.56万
依托单位：
Saitama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650447/
关键词：
seismic behavior ground foundation pile 基礎-地盤-杭相互作用地震応答

项目摘要

The objective of this research are, 1) to develop the response analysis method of the RC structural system considering the interaction between the foundation and the surrounding ground, 2) to verify the method by the result of the model loading test of RC pile in soil, and 3) to consider the seismic behavior of RC structure affected by the response of the piles and soil. Finally, the fruits from these considerations will be made good use for improving the seismic design method of RC structures.In this year, the static and dynamic loading tests of RC model piles in soil are performed. The specimens are fixed on the bottom of the steel soil box, to model the condition at the base in real case. The soil box with pile specimen is filled by the dry sand of which the material properties are clear. The reversed cyclic load or the dynamic sine wave load is acted at the pile top, modeling the seismic load transmitted from footing to pile. In addition, the response analyses of RC structural system, consists of surrounding ground, piles, footing, pier and superstructure, are performed using 3-dimensional elasto-plastic finite element method. From these results, the following points are clarified ; (1) The plastic area of RC pile, i.e. plastic hinge, spreads to lower due to reversed cyclic loading. Additionally, the behavior of the pile is affected by the stiffness of surrounding ground, but not by the shape of the cross section of the pile. (2) The settlement of the ground is observed at the surface around the pile top due to the reversed cyclic loading. This phenomenon causes the compaction of the ground around the pile and the damage of the pile proceeds with the increment of stiffness of surrounding ground. (3) The analytical method used in this research can evaluate the behavior of RC pile in ground to some extent.

这项研究的目的是：1）考虑基础与周围地面之间相互作用的RC结构系统的响应分析方法，2）通过在土壤中RC桩的模型加载测试验证该方法，以及3）考虑受桩和土壤反应影响的RC结构的地震行为。最后，这些考虑因素的果实将充分利用改善RC结构的地震设计方法。在今年，进行了土壤中RC模型桩的静态和动态载荷测试。样品固定在钢质土壤盒的底部，以实现实际情况下的状态。带有桩标本的土壤盒充满了材料特性清晰的干砂。反向的循环载荷或动态正弦波载荷作用在桩顶，对地震载荷从地下传输到桩进行建模。此外，RC结构系统的响应分析由周围的地面，桩，基础，码头和上层建筑组成，使用三维弹性塑料有限元方法进行。从这些结果中，阐明了以下几点；（1）RC桩的塑料面积，即塑料铰链，由于循环载荷反向而扩散到较低。另外，桩的行为受周围地面的刚度的影响，但不受桩的横截面的形状。（2）由于循环载荷相反，在桩顶的表面上观察到地面的沉降。这种现象导致地面的压实在桩周围，桩的损坏以周围地面刚度的增加而进行。（3）本研究中使用的分析方法可以在某种程度上评估RC桩的行为。