摘要
基于能量原理建立预应力锚杆复合土钉支护体系的简化力学模型,分别对土体、土钉、锚杆应力—应变规律进行了分析。首先,对于土体,主要考虑基坑开挖产生的塑性变形,包括体应变与剪应变;其次,对于土钉,根据潜在滑移面界定的主动区与被动区,由剪应力及相对位移分别求解能量方程;再次,对于锚杆,在介绍承载机理与侧阻力计算模型的基础上,推导了锚固体单元的能量方程;最后,考虑土钉与锚杆的相互作用,假定预应力的影响范围,估算了预应力水平分力及竖向分力对滑移面任一点土体产生的附加应力。研究结果可以为该类工程设计提供较好的理论依据。
The simplified mechanical model of prestressed rock bolt and soil nail composite supporting system was established based on energy principle and the soil,soil nail and rock bolt stress-strain law were analyzed respectively.Plastic deformation including the volumetric strain and shear strain caused by foundation pit excavation was mainly considered for soil,energy equation was solved by shear strain and relative displacement for soil nail according to the active zone and passive zone defined by the potential slip surface,the energy equation of the anchor solid element was deduced by introducing the load bearing mechanism and calculation model of side resistance,and additional stress of the slip surface soil at any point produced by prestress horizontal component and vertical component was predicted by considering interaction between soil nail and rock bolt and assuming the prestress influence range.The results could provide a good theoretical reference for similar engineering design.
出处
《铁道建筑》
北大核心
2015年第7期78-82,共5页
Railway Engineering
基金
国家自然科学基金项目(41072224)
河南理工大学青年基金项目(Q2015-6A)
关键词
能量方程
土体
土钉
预应力锚杆
预应力
Energy equation
Soil
Soil nail
Prestressd rock bolt
Prestress
