摘要
由于周边土体的扰动,高压电缆盾构隧道在运营阶段出现了变形、开裂和漏水等病害。以广州地区内径为5.4 m的高压电缆盾构隧道为依托,通过建立三维精细化单环电缆隧道有限元模型,研究地表单调超载和超载再卸载情况下的隧道整体变形、椭圆度、接头张开量和螺栓应力的变化情况。结果表明,当单调超载不大于92 kPa时,隧道处于安全状态;当超载大于146 kPa时,裂缝在拱顶位置出现贯穿,螺栓应力逼近屈服强度,认为隧道已经损坏;多次超载再卸载过程中,第一次卸载时的残余变形最大,且接头的残余变形较整环更显著。
During the operation period,the shield-driven tunnel for high-voltage was subjected to such diseases as large deformation,cracking and water leakage,due to the disturbance of surrounding soil.Based on the 5.4 m diameter shield cable tunnel in Guanghzou city,the three-dimensional elaborate numerical model for one-ring shile cable tunnel was established.The transverse deformation,ellipticity,joint opening and bolt stress were analyzed for two different loading conditions,one is monotonical loading from surface surcharge,and the other is loading and uloading repeatedly.It is shown that,the tunnel kept in safe condition when the monotonic surface surcharge was not exceed 92 kPa.When the surcharge increased to 146 kPa,the crack propagated through the depth of tunnel segment at the crown and the bolt sress approached to its yeild strength,which might indicate the failure of shield cable tunnel.For the case of loading and unloading repeatedly,at the first unlaoding the residual deformation was the largest,and the joint residual deformtion was larger obviously.
作者
王彦峰
刘庭金
余克鹏
郭金根
梁爱武
Wang Yanfeng;Liu Tingjin;Yu Kepeng;Guo Jingen;Liang Aiwu(Research Center of Grid Planning,Guangdong Power Grid Co.,Ltd.Guangzhou 510080,China;South China University of Technology Guangzhou 510641,China)
出处
《广东土木与建筑》
2020年第7期46-49,54,共5页
Guangdong Architecture Civil Engineering
基金
中国南方电网公司科技项目(GD-KJXM-20172975)。
关键词
地表超载
卸载
盾构隧道
横向变形
椭圆度
管片
surface surcharge
unloading
shield-driven tunnel
transverse deformation
ovality
segmental lining
