摘要
利用极限分析有限元方法和下限定理,分析计算了考虑土体自重的临近基坑(边坡)条形浅基础c-?土地基极限承载力下限解。作为一种简化手段,分别按土的粘聚力、基础埋深(超载)和土的自重这3项承载力影响系数表达临近基坑地基极限承载力,获得了基础位置、基坑开挖的边坡角度以及土的内摩擦角取不同值时,相应的地基承载力系数下限解答,并对计算结果进行了讨论。最后将计算结果与已有文献资料以及利用多滑块Prandtl破坏模式得到的极限分析上限解答进行了分析对比,从上、下限给出了临近基坑既有建筑物地基承载力系数取值范围及其承载力上、下限平均值时的减损因数,分析了影响计算结果的因素。
The lower-bound solution for bearing capacities of existing strip footings locat on the top of excavated slope was obtained by using finite elements and linear programming. As accepted in other proposals, the estimate of the limit load near an excavation was obtained herein respectively from the cohesion, the footing depth （overburden） and the soil weight. The results with various footing locations, slope angles and internal friction angles were given in terms of the bearing capacity coefficients, and their characteristics were discussed. Furthermore, the results were compared to those from the reference and the upper-bound solutions by using multi-blocks of Prandtrs collapse mechanism. Finally, the reduction factors were calculated according to the average values between lower and upper bound. The possible influences on the solution of the present method were also discussed.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2006年第8期1044-1048,共5页
Chinese Journal of Geotechnical Engineering
基金
国家科学技术部专项研究基金项目(2002EG231201)
关键词
承载力减损
条形基础
极限分析下限解
临近基坑
bearing capacity reduction
strip footing
lower bound of limit analysis
adjacent to excavations
