权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study on Expansion and Reconsolidation Properties of Soft Ground by Preload

预压软土地基膨胀与固结性能研究

基本信息

批准号：
11650513
负责人：
TONOSAKI Akira
金额：
$ 1.47万
依托单位：
Kanazawa Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

The preloading method is often utilized as promotion of the consolidation settlement and reduction in the long term settlement. It is necessary fact of the anisotropy consolidation clay in which the deformation behavior in loading and unloading is clarified in order to accurately predict the behavior of soft ground after preloading and unloading in the highway embankment.This study in order to consider preloading period which is a basis of this method, anisotropy consolidation test on the assumption of highway embankment was carried out, and the comparison between anisotropy consolidation characteristic and K0 consolidation test result by the preloading was examined. Main conclusion got in this study as be shown in the following.1) The expansion index κ for the calculation of the elastic modulus estimates the excessive expansion from the inaccurate setting which originates from the nonlinearity of e - log p relation of water absorption dilatation process.2) The volumetric strain quantity decreases in comparison with the K0 consolidation, as stress ratio K(σ3/σ1) in the anisotropy consolidation decreases, and the axial strain increases. That is to say, the danger removed, before it reaches degree of the consolidation which the preloading load scheduled, was indicated in case of the highway embankment which receives the anisotropy consolidation.3) The expansion in the unloading decreases the as thing which stress ratio K in the anisotropy consolidation is small.4) From the average principal stress fixed unloading test, the dilatancy coefficient in the unloading was about 1/3〜1/4 in the loading.

堆载预压法常用于促进固结沉降和减少长期沉降。为了准确预测公路路堤软土地基在预压和卸载后的变形特性，必须明确各向异性固结粘土在加卸载过程中的变形特性，本研究以考虑预压时间为基础，在假定公路路堤的情况下进行了各向异性固结试验，并将各向异性固结特性与预压固结试验结果进行了对比。主要结论如下：1）计算弹性模量的膨胀指数κ估计的膨胀量过大，是由于吸水膨胀过程中e-log p关系的非线性引起的; 2）体积应变量相对于K 0固结有所减小，随着各向异性固结应力比K（σ3/σ1）的减小，轴向应变增大。3）各向异性固结中的应力比K越小，卸荷中的膨胀量越小; 4）从平均主应力固定卸荷试验来看，卸荷中的膨胀量越大，卸荷中的膨胀量越小，卸荷中的膨胀量越大。卸载时的粘性系数约为加载时的1/3 ~ 1/4。