石灰改良膨胀土强度影响因素研究

依托新建天门至潜江铁路路基工程，采用直剪试验，研究石灰改良膨胀土强度与干密度、含水率、石灰掺量、养护时间的关系。结果表明:干密度、含水率、石灰掺量、养护时间均影响石灰改良膨胀土剪切强度。其中，干密度、含水率、养护时间主要影响黏聚力，石灰掺量主要影响内摩擦角，另外养护时间对黏聚力的影响比对内摩擦角的影响大，黏聚力在3~15天内变化最快，后期黏聚力变化趋于缓慢。

Study on Influence Factors of the Strength of Lime Improved Expansive Soil

The relation of the strength of lime improved expansive soil to the dry density, moisture content, lime amount and curing time is researched based on the subgrade project of the newly-built railway from Tianmen to Qianjiang and using direct shear test. The results show that the dry density, moisture content, lime amount and curing time influence the shear strength of the lime improved expansive soil, where, the dry density, moisture content and curing time influence the cohesion, the lime amount influences the internal friction angle. In addition, the curing time has greater impact on cohesion than internal friction angle. The cohesion changes rapidly within 3~15 days and goes slow in later period.