坚硬黏性土遇水膨胀和软化工程特性研究

Study on engineering characteristics of swelling and softening of hard cohesive soil meeting water

为研究某国外工程中坚硬黏性土遇水膨胀和软化的工程特性与规律,通过室内土工常规试验和特殊试验2种方法,开展了泡水2 d、4 d、8 d的限制膨胀泡水快剪试验和泡水预压固快试验等特殊试验,将特殊试验成果与常规试验成果进行对比分析,总结了坚硬黏性土遇水膨胀软化后强度降低的程度,强度降低与浸泡时间的关系,限制膨胀泡水对强度降低的影响,泡水对内聚力和内摩擦角的影响等,可为今后的工作提供借鉴和指导。

In order to study the engineering characteristics and laws of swelling and softening of hard cohesive soil meeting water in a foreign project,conventional laboratory geotechnical tests and special tests were carried out,during which limiting expansion quick shear test and preloading consolidated quick shear tests,with soil soaked in water for 2,4 and 8 days,and the results of the special tests were compared and analyzed with the results of conventional tests.The paper summarizes the degree of strength reduction of hard cohesive soil after its swelling and softening in water,the relationship between strength reduction and soaking time,the influence of limiting expansion and soaking on strength reduction,the influence of soaking on cohesion and internal friction angle of soil,and so on,and providing reference and guidance for future work.