摘要
加筋土挡土墙是国内外广泛采用的挡土墙建设技术。由于交通荷载的急剧增加和该类挡土墙的固有缺陷,国内有多处加筋土挡土墙产生变形甚至倒塌。以山东省荷泽市人民路立交桥加筋土挡土墙失稳为例,对其失稳的内在根源和力学机制进行分析。通过多种加固方案对比,确定以压力注浆、双向斜拉预应力锚固、挂网喷射混凝土等技术为主的综合加固治理方案;运用数值模拟层次分析方法,分别对实施不同技术措施所产生的加固效果进行分析。研究结果表明,斜拉预应力锚杆抑制失稳加筋土挡土墙上部的纵向开裂和墙趾剪切破坏带的塑性滑移,并提供较高的抗拉强度、刚度和较快的增阻速度;混凝土喷层使墙面弧形外鼓得到约束。经现场实施综合加固方案,监测结果显示加固工程取得预期效果,表明该技术方案对类似问题具有推广应用价值。
Reinforced earth retaining wall is a widely used construction technique of retaining walls.Because of the rapid increase in traffic loads and the inherent defects associated with such a kind of reinforced earth retaining wall,many of them fail after operation for a period of time in China.A case study is carried out based on a failed reinforced earth retaining wall in overpass along Renmin road,Heze City of Shandong Province.The reasons of failure and its mechanical mechanism have been analyzed through numerical simulation.By comparison of a few reinforcement means,a comprehensive reinforcement scheme is determined,which frames the pressure grouting,the double directions and inclined applied prestressed anchorage,and the shotcrete with the wire mesh reinforcement.The reinforcement effects given by different techniques have been analyzed by using numerical step analysis method.The results indicate that the inclined applied prestressed anchorage restrains the vertical fractures developed in the upper part of the wall and shear band in the foot corners,providing a higher tensile strength,stiffness and a faster increase in resistance velocity as well.Meanwhile,the convex deformation in the side wall has been controlled by the shotcrete.The application of the reinforcement in site achieves the expectation regarding to the monitored results.It proves that the comprehensive reinforcement scheme has an extent value to the similar engineering.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2007年第A01期3086-3091,共6页
Chinese Journal of Rock Mechanics and Engineering
关键词
土力学
加筋土挡土墙
失稳
压力注浆
预应力锚固
喷射混凝土
数值模拟
soil mechanics
reinforced earth retaining wall
failure
pressure grouting
prestressed anchorage
shotcrete
numerical simulation
