中文摘要：

湿胀干缩是膨胀土的一个典型特征。膨胀土与水作用时，随着含水量的增加，其体积将明显地增大，显示了强烈的膨胀性。当这种膨胀性受到限制时，必然产生膨胀力。膨胀力的大小与膨胀土的含水量和干密度有很大关系，研究膨胀力对深入了解膨胀土的变形和强度特性很有价值。通过12个三向膨胀力试验，研究了南阳陶岔重塑膨胀土膨胀力随含水量和干密度的变化规律。试验结果表明重塑膨胀土的三向膨胀力不等，水平膨胀力小于竖向膨胀力；给出了膨胀力与初始含水量和干密度的关系式，为工程建筑物的稳定分析提供了依据。

英文摘要：

Expansive soil is a kind of special unsaturated soil. Expansive soil swells when imbibing water. When the swelling strain was restricted, the swelling pressure would be produced. Swelling pressure occurs not only in vertical dimension, but also in lateral. A series of tests were conducted for the unsaturated expansive soil. The three-dimension expansibility of expan- sive soils were received. According the test results, three-dimensional swelling pressure were unequal. The lateral swelling pressure was smaller than vertical swelling pressure. The formula of vertical expansibility with initial water content and dry density Was given.