台阶式加筋挡墙稳定所需加筋力计算方法与影响规律  

Required strength of geosynthetics in reinforced multi-tiered wall

作　　者：张飞[1,2] 贾世林 朱玉明 陆晓义 舒爽 ZHANG Fei;JIA Shi-lin;ZHU Yu-ming;LU Xiao-yi;SHU Shuang(Key Laboratory of the Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing,Jiangsu 210024,China;Jiangsu Research Center for Geotechnical Engineering Technology,Hohai University,Nanjing,Jiangsu 210024,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210024 [2]河海大学江苏省岩土工程技术工程研究中心,江苏南京210024

出　　处：《岩土力学》2021年第11期3079-3089,共11页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.52078185,No.51878248)。

摘　　要：基于极限平衡法提出了一种台阶式加筋挡墙稳定所需加筋力的计算方法,结合筋材的前、后端抗拔强度确定了各层加筋力分布和面板-筋材连接强度,与已有文献中的试验和数值结果对比,验证了该方法的有效性。通过开展参数敏感性分析,揭示了相关设计参数对台阶式加筋挡墙稳定性与滑裂面的影响规律。分析结果表明:美国联邦公路局所采用的土压力理论会保守地估计台阶式加筋挡墙稳定性;增加台阶宽度和挡墙级数,可以避免加筋挡墙因上部筋材长度不足引起的复合破坏;高挡墙台阶处面板连接强度陡增,墙趾应设置一定埋深防止面板连接破坏;台阶临界宽度以滑裂面位置判别为0.7~0.8倍的下级墙高,以加筋力分布判别则与FHWA保持一致。Based on the limit equilibrium method, stability analyses of the reinforced multi-tiered wall are conducted to calculate the required strength of geosynthetics. The available reinforcement tensile capacity against the front and rear-end pullout is used to determine the distribution of the required strength and the strength of connection to the facing for each layer. The calculated solutions are compared with the results obtained from the experiments or numerical simulations for the verification of the presented method. A series of parametric study is carried out to investigate their influences on the stability of reinforced multi-tiered wall and its critical failure surface. Several conclusions are drawn from the results. Compared with the calculated results of this study, the active earth pressure theory recommended by FHWA could conservatively estimate the stability of the multi-tiered wall. The composite failures due to the insufficient reinforcement length can be avoided by increasing offset distance and number of tiers. The connection strength can suddenly increase at the step and then the bottom facing block should be embedded at a deep depth to prevent the connection damage. The critical offset distance is 0.7-0.8 times of the height of the lower wall judging from the critical failure surface, but the value determined by the distribution of reinforcement tensile strength is consistent with that of FHWA.

关 键 词：加筋土 挡墙 稳定性分析 极限平衡 台阶 

分 类 号：TU470[建筑科学—结构工程]