干湿循环条件下碾压膨胀土的裂隙发展规律  

The development of cracks of compacted expansive soil under dry-wet cycling

作　　者：杨和平[1] 刘艳强[1] 李晗峰[1] 

机构地区：[1]长沙理工大学特殊土工程研究所,湖南长沙410004

出　　处：《交通科学与工程》2012年第1期1-5,共5页Journal of Transport Science and Engineering

基　　金：国家自然科学基金资助项目(50978035);交通部科技项目(2009353311060);广西交通科技项目(2011-20)

摘　　要：为探讨公路工程中膨胀土路基裂隙的开展过程和演化规律,设计并开展了室内模拟试验,初步获得压实膨胀土中裂隙的发育过程及随干湿循环作用次数的变化规律.运用MATLAB的图像处理功能,对开裂试样进行了定性描述和定量统计分析.分析结果表明:初始状态下,试样中产生的裂隙细微短小,裂隙率较低;首次干湿循环作用后,试样裂隙率大幅提高,且开裂宽度和深度急剧加大;但经随后几次干湿循环的作用,裂隙的增长率逐步减小并趋于稳定.研究结论对指导膨胀土路基施工有一定意义.In order to study the development process and evolution of cracks of expansive soil embankment in actual highway engineering, a laboratory simulation tests are de- signed, the development and the change of cracks of compacted expansive soil with the numbers of dry-wet cycling are obtained, and the crack rates of the samples are de- scribed and quantitative analyzed with the graph and image processing of MATLAB. The tests and the analysis results show that the cracks of the expansive soil under the compact condition are fine, and the crack rate is small, the first dry-wet cycling can greatly increase the crack rate of the expansive soil, the width and depth are also in- creased. However, the effect of the following dry-wet cycles on the crack rates are grad- dally decreased. This study can provide certain significant guidance for the construction of expansive soil embankment.

关 键 词：干湿循环 压实膨胀土 室内模拟试验 图形图像处理 裂隙率 

分 类 号：U416.167[交通运输工程—道路与铁道工程]