Study on the substantial increase in the seismic stability of reinforced soil structures by preloading and prestressing

预压和预应力大幅提高加筋土结构抗震稳定性的研究

基本信息

批准号：
09555149
负责人：
TATSUOKA Fumio
金额：
$ 7.04万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555149/
关键词：
Reinforced soil structures Seismic stability preloading and prestressing Model loading tests Shaking table tests Granular material Geotextile High seismic load ジオテキスタイル補強土交通荷重地震荷重原位置測定

项目摘要

The basic mechanism of substantial increasing the seismic stability of reinforced soil structures by preloading and prestressing was studied by performing static cyclic loading tests and shaking table tests on small-scaled models of pier structures. Based on the proposal of the researchers, a prototype bridge pier for a railway bridge of geotextile-reinforced gravel has already been constructed near the Hakata station in Kyushu three years ago. The gravel backfill of the structure that was reinforced with a number of horizontal geotextile layers was preloaded in the vertical direction before having been fixed to prestressed conditions. The model test results showed that reinforced structures become very strong under seismic loading conditions as far as a sufficiently large prestress was maintained. When the input seismic load was a long period of uniform sinusoidal waves with an amplitude of 700 gals at a frequency that was nearly the same with the natural frequency of the structure, the nearly-resonance response at the top of the structure was as high as 2,000 gals. Even in that case, the structure exhibited only a limited amount of cyclic lateral displacement with some residual vertical compression. A method for maintaining prestress when the structure is exhibiting settlement was examined and found effective and practical. Geotechnical analysis of the test results was made for developing the design method.

通过对小型码头结构的小型模型进行静态循环载荷测试和摇晃表测试，研究了通过预加载和预应力来实现增强土壤结构的地震稳定性的基本机制。根据研究人员的提议，三年前的Hakata车站附近已经建造了一座原型的桥梁桥梁，用于土工布增强砾石的铁路桥。在固定到预应力条件之前，先预加载了用多个水平土工布层加固的结构的砾石回填。模型测试结果表明，在保持足够大的预应力的情况下，在地震载荷条件下，增强结构变得非常强大。当输入地震载荷是长时间的均匀正弦波，幅度为700 GAL的频率与结构的固有频率几乎相同时，结构顶部的几乎谐振响应高达2,000 gal。即使在那种情况下，该结构也仅显示出有限的循环横向位移，并具有一些残留的垂直压缩。检查结构的结构定居点时维持预应力的一种方法，并发现有效且实用。为开发设计方法进行了测试结果的岩土技术分析。