基于拟动力法抗滑桩加固非饱和土边坡稳定性分析  

Seismic Stability of Unsaturated Soil Slopes Stabilized by Anti⁃slide Piles Based on Pseudo⁃dynamic Approach

作　　者：王龙 陈国兴[2] 胡伟[3] 周恩全[4] 孙德安[5] WANG Long;CHEN Guoxing;HU Wei;ZHOU Enquan;SUN Dean(School of Environment and Civil Engineering,Jiangnan University,Wuxi 214122,China;Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 211816,China;State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection,Chengdu University of Technolo-gy,Chengdu 610059,China;Faculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang 212013,China;School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China)

机构地区：[1]江南大学环境与土木工程学院,江苏无锡214122 [2]南京工业大学岩土工程研究所,江苏南京210009 [3]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [4]江苏大学土木工程与力学学院,江苏镇江212013 [5]上海大学力学与工程科学学院,上海200444

出　　处：《防灾减灾工程学报》2023年第6期1386-1394,共9页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(52208345);成都理工大学地质灾害防治与地质环境保护国家重点实验室开放基金项目(SKLGP2022K002);江苏省自然科学基金项目(BK20210479)资助。

摘　　要：基于极限分析上限原理和拟动力法,提出一种半解析改进水平片分法,计算具有非线性分布特征的非饱和土重力和地震惯性力所做外功率,将传统塑性理论扩展至非饱和土中以考虑基质吸力对桩侧阻力的提升作用,与解析解对比验证了该方法的合理性。通过算例分析,揭示了吸力对非饱和土边坡稳定性及抗滑桩加固效果的强化作用,探究了非饱和土边坡的地震响应规律,研究了抗滑桩布设参数对支挡结构边坡稳定性的影响规律。研究结果表明:吸力对边坡稳定性的提升效果可达20%~50%,吸力效应与地震动特性密切相关,在地震波达到峰值时显著增强;水平和竖向加速度系数以及土剪切模量对边坡地震稳定性影响较大;桩距D1/dp≤4时,抗滑桩加固效果较为显著并随摩擦角的增加得到强化,抗滑桩最佳桩位位于边坡中上部,且随摩擦角的增加逐渐减小,对应的加固效果也有所降低。Based on the upper bound limit analysis theorem and the pseudo-dynamic approach,a modi-fied horizontal slice method is proposed to calculate the work rates of soil gravity and seismic inertia forces,both characterized by evident nonlinear distribution features.Traditional plasticity theory is ex-tended to unsaturated soils to account for the influence of soil suction on the resistance forces acting on piles.The proposed method is validated by comparing it with analytical solutions.A series of paramet-ric analysis are conducted regarding the impacts of soil suction and pile design parameters on soil slope stability.The results show that the slope stability is underestimated by 20%~50%when soil suction is not considered in practice.The suction effect depends on seismic excitations and is significantly en-hanced when the seismic wave approaches its peak.The horizontal,vertical acceleration coefficients,and the soil shear modulus all have a great influence on seismic slope stability.When the pile spacing D1/dp≤4,pile reinforcement becomes obvious and increases rapidly as the internal friction angle in-creases.The optimum pile location commonly lies in the middle and upper part of the slope.The opti-mum pile location gradually decreases,and the pile reinforcement is slightly reduced as the internal friction angle increases.

关 键 词：非饱和土边坡 极限分析 抗滑桩 拟动力法 基质吸力 

分 类 号：TU43[建筑科学—岩土工程]