上覆荷载和厚度对原状膨胀土膨胀量的影响分析

The Effect of Upper Load and Thickness on the Expansion of Undisturbed Expansive Soil

以兰新高铁一处典型原状膨胀土为对象,通过对膨胀土进行初始含水率为6%,厚度分别为2、4、6 cm及0、10、20、30、40、50 kPa不同上覆荷载下膨胀量试验,以研究厚度和上覆荷载对原状膨胀土膨胀量的影响。试验结果表明:随着上覆荷载的增大,膨胀量逐渐减小,因而膨胀土地基的膨胀变形主要发生在浅层膨胀土;原状土膨胀量随着厚度的增加而增加,且为非线性关系;对试验结果进行拟合,得到膨胀量随上覆荷载及厚度变化关系拟合关系式,为今后膨胀土地区工程建设提供理论支撑。

This paper studies the effect of upper load and thickness on the expansion of undisturbed expansive soil of Lanzhou to Urumqi High Speed Railway.The swelling quantity tests on initial water content of 6%and thickness of 2 cm,4 cm,6 cm under different upper loads(0,10,20,30,40 kPa and 50 kPa)conclude that as the inhibition of expansion declines with the increasing of upper load,the swelling deformation of expansive soil foundation mainly occurs in shallow soil.The inhibition of expansion increases with the increasing of thickness,indicating a non-linear relation.The relationship between the upper load and the thickness is obtained,which provides some theoretical support for future project construction in expansive soil area.