基于渗流-应力耦合的基坑变形与稳定分析.pdfVIP

学兔兔 江苏建筑 2010年第6期(总第 138期) 77 基于渗流一应力耦合的基坑变形与稳定分析 赵士文 ，卢延浩 ，刘仲秋 ( 河海大学岩土所。江苏南京 210098； 山东农业大学水利土木工程学院，山东泰安 271018) f摘 要】 为了研究基坑开挖过程中渗流场与应力场的变化规律及其导致的基坑稳定问题，基于广义Biot固结理论给出 了饱和渗流一应力耦合理论控制方程：进而结合有限元理论分析了某基坑开挖过程中不同排水边界条件和卸载方向对基坑 稳定性的影响。结果表明．排水边界条件对基坑塑性区、孔隙水压力和位移的趋势影响不大；水平方向的卸载对上述因素的 影响较垂直方向大。 『关键词1 基坑；渗流一应力耦合；排水边界；卸栽 [中图分类号]TU441．6 【文献标识ra-q]A [文章编号]1005-6270(2010)06-0077-03 Deformation and Stability Analysis of Foundation Pit Excavation Based on Hydro-Mechanical Coupling Theory ZHAO Shi—wen‘ LU Ting—hao LIU Zhong-qiu (1．Research Institute of Geotechnical Engineering，Hohai University，Nanjing Jiangsu 210098 China； 2．College of Water Conservancy and Civil Engineering，Shandong Agricultural University，Tai’an Shangdong 271018 China) Abstract： In order to research the variation law of seepage field and stress field during excavation and its in— fluence on the problems of stability of foundation，governing equations of saturated hydro—mechanical coupling theory are provided based on generalized Biot’S theory．Then the stability analysis of foundation pit excavation with different drainage boundaries and unloading directions is carried out through FEM simulation．The results indicate that the drainage boundary has little effect on distribution form of plastic zone，pore pressure and dis— placement for foundation pit；but the unloading of horizontal direction has more effect on those factors than that of vertical direction． Key words：foundation pit；hydro-mechanical coupling；drainage boundary；unloading 0 引言 常采用的模型．该模型将裂隙岩体等效为非均质各向异性 在地下水丰富的地区基坑内外存在着很大的水头差． 的连续孔隙介质进行模拟，用连续介质理论描述渗流方程。 由坑内降水或围护结构渗漏导致的渗透破坏问题严重威胁