地下圆形隧道开挖卸荷围岩弹塑性分析  

Elastic-Plastic Analysis of Underground Circular Tunnel under Rock Excavation Unloading

作　　者：王新波[1,2] 潘晓明[1] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]核工业井巷建设公司,浙江湖州313000

出　　处：《河南科学》2010年第9期1153-1156,共4页Henan Science

基　　金：中国博士后科学基金项目(20080440652)

摘　　要：针对地下圆形隧道,在分析开挖卸荷的基础上,分别给出了弹性和弹塑性围岩二次应力的计算表达式.在弹性不同侧压力条件下,分析了围压切向应力分布规律,当λ>0.33时,圆形隧洞围岩将不出现拉应力.当围岩处于弹塑性状态时,考虑围岩稳定的前提下,扩大塑性区半径R,就可降低维持极限平衡状态所需的支护抗力pi,充分发挥了围岩的自承作用.On the basis of analysis of excavation unloading,this paper proposes the secondary stresses expression of surrounding rock in elastic state and elastoplastic state for the underground circular tunnel.Under elastic different conditions of lateral pressure,distribution of the tangential stress is analyzed,when the surrounding rock will not appear circular tensile stress in the surrounding rock.As λ0.33,the surrounding rock will not appear circular tensile stress.When the rock in the plastic state,considering the stability of the surrounding rock,if plastic zoneradius R is enla rging,then the support resistance pi which keep the state of limit equilibrium can be lessen.In this way,the self-supporting of surrounding rock can be brought into full paly.

关 键 词：围岩 二次应力 弹塑性分析 支护压力 

分 类 号：TU452[建筑科学—岩土工程]