未打穿散体材料桩复合地基固结简化解研究  

Study of simplifying solution to consolidation of composite ground with partially penetrated granular columns

作　　者：张玉国[1] 孙敏[1] 谢康和[2] 

机构地区：[1]中原工学院建筑工程学院,郑州450007 [2]浙江大学岩土工程研究所,杭州310027

出　　处：《岩土力学》2014年第5期1303-1310,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.U1204511);河南省教育厅自然科学研究项目(No.2008A560016);河南省基础与前沿技术研究(No.112300410286)

摘　　要：利用平均固结度普遍解,将未打穿散体材料桩复合地基转化为等效双层地基,推导出未打穿散体材料桩复合地基固结简化解,给出其平均固结度计算简化公式。根据简化解、现有解和有限单元法编制程序,绘制考虑贯入比、桩体渗透系数、土体扰动区渗透系数和土体扰动区影响因子等因素对固结的影响曲线图,分析了各因素对未打穿散体材料桩复合地基固结性状的影响,并对3种计算方法所求出的平均固结度进行了比较研究,进而探讨了简化解的适用性。研究结果表明,无论是在单面排水还是在双面排水条件下,简化解求出的平均固结度总体上是介于现有解和有限单元法二者之间,尤其在固结过程的"中后期"(即固结度≥50%时)。从实用角度来看,简化解的计算结果具有足够精度,且简便、实用;在各种影响因素中,散体材料桩长度和桩体渗透系数对固结过程的影响最大。A composite ground with partially penetrated granular columns is turned into a equivalent-double-layered ground on the basis of the general solution of the average degree of consolidation; and its simplifying analytical solution of 1D consolidation is worked out; furthermore, the simplifying formula of the average degree of consolidation is gained. Based on this solution, the present existing solutions and finite element method, these relevant programs are programmed. The consolidation process is investigated and the relevant results are prepared in graph forms which considering the influence of some factors including penetration ratio, permeability coefficient of a granular column, permeability coefficient of disturbed soil and impact factor of disturbed zone. The influence of various factors on the consolidation behavior of composite ground with partially penetrated granular columns is analyzed; and the comparative study of the average consolidation degrees by the three calculation methods is carried out; and then the applicability of the simplifying solution is discussed. The research results show that, the average consolidation degree of the simplifying solution under single-sided drainage or double-sided drainage conditions is between the ones of the existing solutions and the finite element method; and especially in the middle-latter of the consolidation process （≥ 50% degree of consolidation）, the results of the simplifying solution meet the engineering precision requirements; and it is simple, and practical; and in the various influencing factors, both length and permeability coefficient of granular column have the most effects on the consolidation process.

关 键 词：散体材料桩复合地基 未打穿 等效双层地基 平均固结度 解析解 

分 类 号：TU470[建筑科学—结构工程]