粘粒含量对砂土静动力液化影响的试验

摘要

含一定粘土颗粒的砂土在一定条件下易发生静态和动力液化的现象，且粘土对砂土的抗液化影响规律较为复杂。为了研究粘粒含量对砂土液化的影响规律，通过静力三轴仪和动力三轴仪试验系统，对粘粒含量分别为0％、5％、10％和15％的砂土进行试验。静力与动力的试验结果表明：粘粒含量对砂土抗液化性能的影响并不是单调的，存在一个粘粒含量值（5％～10％）使得砂土的抗液化性能最差。当粘粒含量小于5％时，粘粒会促进孔压的发展；当粘粒含量大于10％时，粘粒会抑制孔压的发展。不同含量的粘粒在砂土颗粒间分别起到润滑与粘结砂粒的作用。%Sand with a certain percent of clay is easily liquefied under static and dynamic loading. Clay has a com⁃plicated effect on the liquefaction resistance of sand. In order to study the influence of clay content on the liquefac⁃tion of sand, sand samples with different clay contents, 0%, 5%, 10%and 15%were investigated with static triax⁃ial and dynamic triaxial test systems. Static and dynamic test results show that the clay content has a non⁃monotonic impact on the liquefaction resistance of sand. The liquefaction resistance of the mixture is poorest when the clay content is about 5%~10%. When the clay content is less than 5%, the clay promotes pore pressure development. When the clay content is more than 10%, the clay suppresses pore pressure development. Different contents of clay play roles of lubrication and cementation between sand particles.