为给膨胀土用于路基填筑的设计与施工提供参考,对膨胀土的膨胀变形量计算方法进行分析。通过对弱膨胀土在不同初始干密度、上覆压力下的一维线膨胀率试验,分析了膨胀土路基湿度平衡规律。结合其他学者的一维线膨胀率试验结果,提出了相对上覆压力和相对变形量的概念。试验结果显示弱膨胀土的相对膨胀变形量与相对线膨胀率呈幂指数关系,并依据试验结果及路基湿度平衡规律建立了膨胀土的湿胀变形模型及路堤填筑膨胀变形量的实用计算方法,解决了影响膨胀土线膨胀率3个主要因素的耦合问题,为膨胀土路堤填筑湿胀变形量的预测提供理论计算方法。

In the aim of providing reference for the design and construction of expansive soil fill in subgrade, the calculation method for the bulging deformation of expansive soil was analyzed. First of all, one-dimensional linear expansive ratio test on weak expansive soil of different initial dry density under varying overburden pressure was conducted, and the law of moisture equilibrium of expansive soil fill in subgrade was expounded. With reference to the results of one-dimensional linear expansive ratio obtained by other scholars, the concepts of relative overburden pressure and relative deformation were put forward. Test results unveiled that the relative linear expansive deformation was in a power exponential relation with relative overburden pressure. In addition, the wet expansive deformation model was established and a practical calculation method for bulging deformation of expansive soil fill in subgrade was proposed to solve the coupling problem of three factors for the linear expansive ratio of expansive soil.