水泥搅拌桩地基下卧层沉降计算方法选择  

Calculating Method Alternation for Substratum Settlement of Cement-Soil Mixing Piles Composite Ground

作　　者：王凤池[1] 朱浮声[1] 张德海[1] 

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168

出　　处：《沈阳建筑大学学报（自然科学版）》2006年第5期705-708,共4页Journal of Shenyang Jianzhu University：Natural Science

基　　金：建设部科学技术项目(06-K1-6)

摘　　要：目的为了研究水泥搅拌桩复合地基设计中的沉降计算问题,减少下卧层沉降计算值与实测值的差异.方法从水泥搅拌桩的加固机理出发,指出了水泥搅拌桩加固区与下卧层相比是一个具有强度高、压缩性小的硬壳层.考虑硬壳层的影响,在进行下卧层沉降计算时,应根据外荷载与总抗剪力的关系来选择计算方法.结果当外荷载大于总抗剪力时,采用等效实体法;反之,则考虑硬壳层效应,附加应力折减.结论硬壳层对附加应力有扩散效应,这是有时采用等效实体法计算下卧层沉降时数值过大的原因.算例表明,通过对计算方法的选择,提高了下卧层沉降的计算精度.In order to reduce the calculating error of substratum settlement in designing cement - soil mixing piles composite ground, the mechanics of the soil reinforced by cement - soil mixing piles were analyzed. Because of high strength and low compression, the reinforced part formed a stiffer layer than the substratum. Considered the influence of stiff layer, when calculating the substratum settlement of cement - soil mixing pile composite foundation, the method must be chosen according to the relationship between loads and overall shear resistances. As loads are bigger than overall shear resistances, the method of equivalent solid mass is adopted;contrawise, the influence of stiff layer must be considered and the additional stress should be reduced. Because the stiff layer can diffuse the additional stress, sometimes the result is too large calculating by the method of equivalent solid mass. A calculating example shows the calculating precision of substratum settlement is improved by choice for the calculating method.

关 键 词：水泥搅拌桩 复合地基 下卧层 沉降 附加应力 

分 类 号：TU443[建筑科学—岩土工程]