水泥搅拌桩返浆铺平下盖层在软基处理中的试验研究

水泥土搅拌法因施工简便,造价低,能有效改善地基土性质,在软土地基处理中得到广泛应用,但在施工过程中出现的返浆问题,给施工进度、经济等带来一些麻烦。结合工程实例,介绍了水泥土搅拌桩(湿法)处理软土地基的施工工艺,阐述了利用搅拌桩顶的返浆铺平作为基础底面的下盖层,以褥垫层进行找平的新方法。复合地基静载试验结果表明:利用新方法处理后的地基沉降量比常规方法约减少一半,由于返浆层的存在,增加了桩的上部土层刚度,有利于提高复合地基的承载力。此方法有效地控制了地基的沉降,缩短了工期,并节约了工程造价。

Experimental Study on Lower Slurry-paved Cap of Cement Soil Mixing Pile in Soft Soil Foundation Treatment

Cement-soil mixing method, which is of simple construction, low cost, and can effectively improve the properties of foundation soil, has been widely used in soft soil foundation treatment; however, slurry appear in the construction process brings some construction progress related and economic troubles. Combining with project case, this paper introduced the construction technology of cement-soil mixing pile(wet method)treatment for soft soil foundation, expounded a new method which takes slurry pavement on the mixing pile top as the lower cap of the foundation bed, and then makes level against the cushion. The result of static load test on composite foundation show that the settlement of the foundation treated by this new method, compared with the conventional method, reduces by half, and due to the layer of slurry appear, the stiffness of the soil layer on the upper part of the pile is improved, which helps to increase the composite foundation’s bearing capacity. This method makes for control of foundation settlement, reduction of construction period and project cost saving.