膨胀性是压实弱膨胀土的典型特征，同时是造成膨胀土构筑物破坏的最重要的原因之一，合理地预估压实弱膨胀土在特定条件下的变形量对于减小构筑物的破坏具有十分重要的作用。因此，建立压实弱膨胀土的膨胀变形计算模式不仅显得十分重要而且也十分必要。基于此，在对压实弱膨胀土线膨胀率的相关影响因素进行分析的基础上，以高淳胥河某边坡弱膨胀土为研究对象，进行了不同初始状态下的膨胀土膨胀变形试验，研究了增湿比、压实度及上覆压力等对膨胀土线膨胀率的影响，建立了考虑增湿比、压实度及上覆压力的压实弱膨胀土线膨胀率变化模型，并采用其他学者的试验数据对该模型进行了成果验证，验证结果表明该模型可以较好地拟合压实弱膨胀土的膨胀变形量。

Swelling is the typical characteristic of weak swelling soil,and is the most important cause of the damage of swelling soil structures.It is of great importance to estimate the deformation of swelling soil in some specific conditions,and it is not only important but also necessary to establish the calculation model for weak swelling soil. In view of this, on the basis of analyzing the influence factors of linear swelling ratio,we carried out swelling deformation tests on weak swelling soil of the slope of Xuhe river in different initial status.We also studied the influences of humidification ratio,degree of compaction and overburden pressure on the linear swelling ratio,and established the calculation model for linear swelling ratio in consideration of humidification ratio,degree of compaction and overburden pressure.Finally we used the test data of other scholars to verify the calculation model,and the verification results showed that the calculation model could well fit the swelling deformation of compacted weak swelling soil.