石灰桩对冻土地基预融效果模型试验研究

在高纬度冻土区修建基础工程,如何处理冻土地基使其满足承载力要求,是冻土工程施工技术的关键。为了研究石灰桩对冻土地基的预融和挤密效果,提出以破坏冻土为出发点的石灰桩放热预融方案。采用石灰桩预融冻土地基,通过群桩和单桩模型试验,测试桩周不同位置土的温度、含水率和密度的变化,确定石灰桩对冻土地基的预融和挤密影响半径。试验结果表明,所选用的桩体材料配合比,能够使桩间一定范围内冻土全部融化,提高桩间土的密度。

Experimental Research on Effect of Lime Pile on Prethawing of Permafrost Foundation

How to deal with the frozen soil and meet the requirements of bearing capacity is the key to the construction in frozen soil in permafrost regions of high latitude,where infrastructure project is to be implemented. In this paper,in order to study the pre-melt compaction effect in the permafrost region,a proposal is forwarded that lime pile is employed to release heat and fulfill pre-melt as the starting point of the destruction of the shallow frozen soil. The lime pile is used as the foundation treatment in permafrost area,the changes of temperature,moisture content and density of the foundation soil in different position and depth are measured through indoor model test to determine the radius of the influence of the lime pile on the pre-thawing and compaction for permafrost foundation. The research results show that the lime pile can thaw the permafrost and raise the density of the soil between piles.