摘要
通过对3个不同土工格栅加筋土高挡墙的现场试验,研究土工格栅加筋土高挡墙的墙底压力、筋材变形及破裂面。研究结果表明:墙底压力的分布存在单峰现象,且墙底压力实测值大于γ.H;筋材变形沿横断面的分布出现双峰现象,墙面附近出现峰值主要是受施工工艺和墙面侧向约束的影响;随着填料填筑高度的增加,筋材变形不断增大,工后观测阶段筋材变形值在一段时间内逐渐减小,即从筋材被拉断这一破坏形式上分析,设计的最不利工况发生在施工阶段末期;对应筋材变形出现的双峰值得出挡墙的2条实测破裂面,破裂面1靠近墙面,不代表主动土压力破裂面,破裂面2代表主动土压力破裂面。因此,建议墙底压力的设计安全储备应提高,筋材的设计要考虑施工工艺和墙面侧向约束的影响。
According to the field test on three different geogrid reinforced earth high retaining walls, wall bottom pressure, geogrid deformation and fracture plane for the retaining wall were analyzed. Research results show that the distribution of wall bottom pressure exists single peak, and the observed value of wall bottom pressure is greater than relevant γ· H. Geogrid deformation distribution along transect exists double peak, the peak value around wall face is mostly affected by the construction technology and lateral restraint of wall face. Geogrid deformation increases continuously with the growth of filling height. Geogrid deformation value gradually decreases in a period of time during post-construction measuring stage, namely the most disadvantageous construction condition occurs at the end of construction stage from the view of the collapse mode of geogrid tensile failure. Double peak in the geogrid deformation distribution leads to two observed fracture planes. The fracture plane 1 which is close to wall face does not represent active earth pressure fracture plane, while the fracture plane 2 does. Therefore, design safety margin of wall bottom pressure should be increased, and the design for geogrid should consider construction technology and lateral restraint of wall face.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2008年第4期1-7,共7页
China Railway Science
基金
交通部西部交通建设科技项目(2003-3187-9917)
关键词
加筋土高挡墙
墙底压力分布
筋材变形
现场试验
土工格栅
Reinforced earth high retaining wall
Wall bottom pressure distribution
Geogrid deformation
Field test
Geogrid
