【摘要】 干湿交替环境下,膨胀土具有反复湿胀干缩变形的特性,容易引起工程建筑物的变形破坏。以南宁地区的击实膨胀土为研究对象,通过室内试验揭示膨胀土在干湿交替环境中的变形规律,探讨了体积变形参数、初始切线模量与循环次数的关系,并对试样绝对残余体变率与初始切线模量的关系进行了分析。研究结果表明:试样的绝对残余体变率随干湿循环次数的增加而递增,但相对残余体变率却逐渐减小,体积变形量稳定时所需循环次数均随含水率变化幅度的增加而递减。更多还原

【Abstract】 Expansive soil presents a repeated swelling-shrinking deformation in the alternation of wet-dry environment,which easily leads to the deformation damages of the engineering constructions.Indoor cyclic wetting-drying tests were conducted on the compacted expansive soil from Nanning area in order to study the deformation of expansive soil in alteration of wet-dry environment.Then,the relationships between the deformation parameters,initialization tangent modulus and cycle numbers were analyzed.In addition,the relationship between the absolute residual volume change rate and initial tangent modulus of soil specimen was discussed.The results showed that the absolute residual volume change rate of soil specimen increased along with the increase of the wetting-drying cycles,but the relative residual volume change rate decreased.The number of the cycles for the variation volume to reach a constant state reduced with the increase of the water content.更多还原