不同温度的干湿循环对膨胀土裂隙面积率的影响分析

摘要

对引江济淮试验工程场地的原状膨胀土进行不同温度的干湿循环作用下裂隙发展的室内试验研究.试验中采用不同温度下的烘干过程模拟不同脱湿速率下的脱湿过程,浸水吸湿是采用抽气饱和法.烘干过程中对土样进行拍摄,以记录该过程下的裂隙发展情况.对图像进行二值化处理以处理得到其裂隙面积率.结果表明,膨胀土裂隙面积率随着温度升高及干湿循环次数的增加呈现增大趋势,其中,低温情况下,膨胀土裂隙面积率随着干湿循环次数的增加,增大率较小,近似线性增大;高温时膨胀土裂隙面积率增大率略大,并在第3次干湿循环过程有显著增大的现象.%Laboratorial test is conducted to study the evolution of the fissures of Huaihe River Engineering Project' s expansive clay under wetting and drying cycles of different temperatures.Oven drying method under different temperatures are employed to simulate the drying process of different drying rates.Vacuum saturating method are employed to simulate wetting process.The specimen is photographed regularly in order to record the development of fissures.Binarization method is employed to process fissure image in order to get the fissures area ratio.It is shown that the fissures area ratio increases as the rise of temperature and the number of wetting and drying cycles.The increasement of the fissures area ratio of expansive clay under wetting and drying cycles of low temperature is linear increasing.The increasement of the fissures area ratio of expansive clay under wetting and drying cycles of high temperature has a remarkable growth during the third weting and drying cycle.