初始状态对膨胀土变形规律的影响  

Effect of Initial State of Expansive Soils on Its Deformation Law

作　　者：程钰[1] 石名磊[2] 周正明[1] 

机构地区：[1]中国科学院武汉岩土力学研究所,湖北武汉430071 [2]东南大学岩土工程研究所,江苏南京210096

出　　处：《公路交通科技》2008年第9期42-46,共5页Journal of Highway and Transportation Research and Development

摘　　要：针对不同初始含水量和初始干密度的中弱膨胀土和石灰改性膨胀土,对上覆压力作用下的变形规律进行了试验研究,得到了其膨胀变形随稠度状态的变化规律。结果表明,稠度状态可以较好地预测上覆压力与线膨胀率之间的关系;稠度状态对膨胀土的影响很大,对同一种膨胀土和其石灰改性土有所不同,随着灰剂量的增加和上覆压力的增大,稠度状态对改性土影响逐渐变小。因此,在膨胀土路基施工过程,应合理考虑上覆压力和稠度状态来分层控制路基的压实。路基下基层可以适当提高填筑的稠度状态,上基层采用相应较低的稠度状态填筑,以减少膨胀率及膨胀力对路基造成的破坏。To moderate weak expansive soils and lime treated expansive soils with different initial moisture contents and initial dry densities, a series of experiment were carried out to investigate their deformation laws under different loadings. Meanwhile the relationship between the swelling and the moist state was established based on the results of experimental tests. It was found that （1） the moist state is a very important parameter for governing the swelling behavior of the expansive soils, which is reasonable for assessing the swelling rate of expansive soils based on moist state and loading; （2） the effect of moist state on the expansive soils is great, while the effect of moist state on the lime treated expansive soils reduces when compacted at a high degree and lime content increases. So during the construction of expensive soil subgrade, the relationship between the moist state and loadings should be taken into account for controlling compaction degree, and moist state should be served as an compaction controlling index to make the compaction embankment more stable.

关 键 词：道路工程 膨胀土 试验研究 初始状态 膨胀率 变形规律 

分 类 号：U416.167[交通运输工程—道路与铁道工程]