南宁膨胀土膨胀变形规律的试验与应用研究

通过不同初始干密度、初始含水率在不同垂直压力下的膨胀变形试验,研究南宁膨胀土的膨胀量与初始干密度、初始含水率以及垂直压力的相关关系。研究结果表明,膨胀量随初始干密度的增大而增加,随初始含水率和垂直压力的增加而减小;通过回归分析发现,膨胀率与初始干密度和初始含水率成线性关系,而与垂直压力成半对数线性关系。在此基础上,建立了南宁膨胀土膨胀率的三元回归方程,并通过某大型模型试验验证了该方程的正确性与实用性。本文所建立膨胀率三元回归方程为简便而准确地预测和估算膨胀土地基的膨胀潜势和差异隆起提供了依据。

Experimental and Applied Research on Swelling Laws of Nanning Expansive Soil

On the basis of the swelling strain tests made in Nanning expansive soil with various initial dry densities and initial water contents under different vertical pressure,the relations are studied between the swelling capacities and the above three factors.The results indicate that the expansion ratio increases with the increase in the initial dry density,while decreasing with the increase in the initial water content and vertical pressure.By means of regression analysis,it proves true that the relation between the expansion ratio and the initial dry density or initial water content is linear,and the relation between the expansion ratio and the vertical pressure is semilogarithmic-linear.The ternary regression equation based on the above relations is established.Its correctness and applicability is verified by some huge model test.The equation becomes the bases for forecasting and estimating the potential and differential swelling of expansive soil foundations.