中文摘要：

以广西宁明灰白重塑膨胀土为研究对象，运用自制“膨胀土三向胀缩测试仪”开展了不同初始含水率和三向压力的膨胀试验，研究了初始含水率和三向压力对胀限、三向膨胀率的影响规律。试验表明，三向等压时，竖向的膨胀率始终大于水平向膨胀率，比值为1.21～1.27，该比值与初始含水率、三向压力无关；三向膨胀时程均可以分为快速膨胀、缓慢膨胀和趋于稳定3个阶段；胀限与三向压力的对数线性相关，与初始含水率无关；相等初始含水率和干密度条件下，三向膨胀率均与三向压力的对数线性相关。

英文摘要：

This paper studies the characteristic of remolded grey expansive soil in Ningming of Guangxi province.A series of swelling tests were conducted for cubic expansive soil of different initial moisture contents and three-directional pressures.The test device is a home-made“three-directional swelling and shrinkage of expansive soil tester”.The tests investigate the natural law of the effects of the initial moisture content and the three-directional pressure to the maximum water content ＆amp;the three-directional expansion rate.According to the test results,the vertical expansion rate is always larger than horizontal expansion rate when three-directional pressure is equal.Their ratio is 1.21~1.27.The ratio is unrelated to the initial moisture content and the three-directional pressure.The time-deformation history of the three-directional expansion rate includes three phases the rapid expansion,the slow expansion and the stabilization.The maximum water content has a linear correlation to the logarithm of the three-directional pressure.But it does not associated with the initial moisture.The three-directional expansion rate has a linear correlation to the logarithm of the three-directional pressure,when the expansive soil has the same initial＆amp;nbsp;moisture content and dry density characteristic.