摘要
基于修正惯用法,计算偏心堆载作用下隧道衬砌环的围压,采用MIDAS/GTS NX软件建立单环管片环的三维有限元模型,计算围压作用下管片环的横向变形及内力情况;提出采用椭圆度作为评价隧道结构变形的评价指标。研究结果表明:在偏心堆载作用下,盾构隧道结构呈现“斜椭圆”变形,在椭圆长轴两端隧道内侧发生挤压的现象,混凝土的应力较大。由于应力集中,管片与管片的接缝处的应力较大;椭圆度同时适用于对称和偏心堆载情况下的安全状态评价,混凝土和螺栓最大应力都随着椭圆度增大而增大,近似呈线性关系。当达到混凝土的屈服应力时,混凝土发生破坏,混凝土最大应力不变,螺栓最大应力增长变快,螺栓最大应力?椭圆度曲线斜率变大。
The confining pressure of tunnel lining ring under eccentric loading was calculated based on the modified inertia method.A three-dimensional finite element model of a single segment ring was established by using MIDAS/GTSNX software,and the transverse deformation and internal force of the segment ring under confining pressure were calculated.Ellipticity was used as an index to evaluate the deformation of tunnel structure.The results show that under the action of eccentric surcharge,the shield tunnel structure presents inclined ellipse deformation,and the inside of the tunnel at the two ends of the long axis of the ellipse is squeezed,and the stress of the concrete is larger.The stress at the joint between the pipe segment and the pipe segment is the largest because of the stress concentration.Ellipticity is suitable for the safety evaluation of symmetrical and eccentric heap.The maximum stress of concrete and bolt increases with the increase of ellipticity and increases approximately linearly.At the yield stress of concrete,the concrete will be destroyed,the maximum stress of concrete will not change,the maximum stress of bolt will increase quickly,and the slope of the maximum stressellipticity curve of bolt will increase.
作者
魏纲
洪文强
魏新江
蒋吉清
WEI Gang;HONG Wenqiang;WEI Xinjiang;JIANG Jiqing(Department of Civil Engineering,Zhejiang University City College,Hangzhou 310015,China;College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China)
出处
《中南大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2020年第3期750-757,共8页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(51778576)
杭州市科委资助项目(20180533B07)。
关键词
盾构隧道
偏心堆载
椭圆度
横断面变形
shield tunnel
eccentric heaped load
ellipticity
cross section deformation