饱和度及干密度对弱膨胀土土水特征曲线影响

采用滤纸法测量不同干密度下试样的总吸力与基质吸力,并绘制相应的土水特征曲线,分析饱和度与干密度对土水特征曲线的影响.实验结果表明:在饱和度一定时,总吸力与基质吸力均随干密度的增大而增大;随饱和度增大,不同干密度的总吸力差值和基质吸力差值逐渐减小;另外,试样的排水速率随饱和度的增大而减小,且干密度越大,排水速率越慢.在较低含水率时,试样的总吸力和基质吸力随干密度的增大而增大,随含水率的增大,干密度对总吸力和基质吸力的影响逐渐弱化.

Analysis of Influence of Saturation and Dry Density on Soil Characteristic Curve of Weak Expansive Soil

The total suction and matric suction of soil samples at different dry densities were measured with the filter paper method, and the corresponding soil-water characteristic curves were drawn. The effects of saturation and dry density on the soil-water characteristic curves were analyzed. The experimental results showed that when the saturation was constant, total suction and matric suction increased with increasing dry density, and with the increase in saturation, the difference between total suction and the matrix suction at different dry density decreased. The drainage rate of the sample decreased as the saturation increased, and the higher the dry density, the slower the drainage rate. At lower water content, the total suction and matrix suction of the sample increased with the increase in dry density, and with the increase in water content, the effect of dry density on total suction and matrix suction became smaller.