Earthquake Response Analysis of Whole Structural System for Reinforced Concrete Structures

钢筋混凝土结构整体结构体系地震反应分析

基本信息

批准号：
16360222
负责人：
MUTSUYOSHI Hiroshi
金额：
$ 7.1万
依托单位：
SAITAMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2005
项目状态：
已结题

项目摘要

Recent earthquakes have stressed the importance of conducting response analysis of a whole structural system including structure, foundation and ground for the performance based design of a structure. For the development of a realistic analytical method, however, it is first imperative to clarify the behavior of pile and soil during earthquakes. The main objectives of this research are to study the seismic behavior of concrete pile and soil using full-scaled lateral loading test and to establish an analysis procedure based on the experiment. Full-scale lateral loading tests were carried out on concrete piles embedded into cohesive soil. Two of the piles were embedded into the ground using inside drilling technique, whereas other two piles were embedded using outside drilling technique with bentonite-cement paste around the pile and soil. The results of the experiments revealed that the lateral load carrying capacity of piles significantly degrades when subjected to cyclic loading compared to the monotonic loading. Three-dimensional non-linear finite element analysis was then carried out to study the behavior of experimental specimens analytically. The analysis implied that interface element should be used between pile and soil surface to simulate the gap formation between the soil and pile. Moreover, the analysis also showed that if the degradation in soil stiffness due to cyclic loading is ignored, the analysis highly overestimates the lateral loading capacity of the pile. It was also found that for the outside-boring pile, bentonite-cement layer has to be considered in the analysis to obtain the actual lateral behavior of pile.

最近的地震强调了对整个结构系统进行响应分析的重要性，包括结构，基础和基础结构的基础。但是，对于一种现实的分析方法，首先必须阐明地震期间桩和土壤的行为。这项研究的主要目的是使用全尺度的侧向加载测试研究混凝土桩和土壤的地震行为，并根据实验建立分析程序。在嵌入凝聚力土壤中的混凝土桩上进行了全尺度的横向载荷测试。使用内部钻孔技术将其中的两个桩嵌入了地面，而另外两个桩则使用外部钻孔技术嵌入，并在桩和土壤周围和膨润土水泥糊嵌入。实验的结果表明，与单调载荷相比，桩的侧载载能力承受循环载荷时会显着降解。然后进行三维非线性有限元分析，以分析实验标本的行为。分析表明，应在桩和土壤表面之间使用界面元件，以模拟土壤和桩之间的间隙形成。此外，该分析还表明，如果忽略了循环载荷引起的土壤刚度的降解，则该分析高度高估了桩的横向负载能力。还发现，对于外部钻孔，必须在分析中考虑膨润土水泥层才能获得桩的实际横向行为。