【摘要】 采用普通固结仪和收缩仪分别进行蒙自重塑膨胀土浸水膨胀变形试验和膨胀土失水收缩变形试验,系统地研究了不同初始状态下膨胀土胀缩变形规律与致灾机制,并应用DoesResponse模型,定量模拟了膨胀土胀缩时程规律。研究表明,蒙自膨胀土胀缩变形差异较大,一般吸水膨胀率远大于失水收缩率,相似状态下试样膨胀系数越大,收缩系数亦越大,表现出较强的各向异性;膨胀土含有的大量细小黏土颗粒与较强的蒙脱石晶体矿物及显著的微结构特征,是其产生强烈胀缩变形灾害的内因与本质,而土中发育的微孔隙-裂隙结构及其初始状态,是发生胀缩变形灾害的外因。更多还原

【Abstract】 Swelling tests of Mengzi remolded expansive soil immersed with water are carried out by simple consolidometer;and shrinkage tests are made by contractometer.The characteristics of expansion and contraction and break-down mechanism for expansive soil under different initial conditions are studied systematically.Does Response model is used to fit quantitatively the rules of swelling and shrinkage time interval for expansive soil.The results show that the difference between swelling and shrinkage for expansive soil is remarkable.Generally speaking,swelling ratio of samples immersed with water is larger than shrinkage ratio.The larger the expansion coefficients of samples under the same conditions are,the larger the contraction coefficients are.The anisotropy of samples is stronger.The internal and essence of shrinkage deformation disaster of expansive soil is that there are a lot of small clay particles,montmorillonite mineral crystal and significant microstructural characteristics.And the external cause is the development of micropore,fracture structure and the initial state.更多还原