曲线顶管顶进管节应力特征试验研究

Experimental Study on Pipe Stress Characteristics of Curved Pipe-jacking

拱北隧道暗挖段综合考虑周围建筑和地质条件等因素,采用曲线顶管管幕施工工法施工。由于曲线顶进方式,管节应力特征较之于普通直线顶管有所不同。加之暗挖段工程顶管管节接头构造特殊,更加大管节应力分布的复杂性。依托中国地质大学(武汉)非开挖工程实验室所研发钢顶管管节应力试验系统,模拟拱北隧道管幕曲线顶管顶进实验,研究管节应力与顶力大小的规律。结果表明:管节应力与顶力正相关的现象,应力在监测断面内水平位置两侧出现应力集中,管道轴线方向应力集中存在接头附近。

Gongbei Tunnel is constructed with curved jacking pipe roof method in comprehensive consideration of surrounding buildings and geological conditions. The pipe stress characteristic of this jacking method is different from that of linear pipe jacking due to different jacking method. Besides,the special structure of the pipe joint increases the complexity of pipe stress distribution. Based on a laboratory test system of steel pipe jacking stress produced by Trenchless Lab of CUG,a curved pipe jacking experiment is simulated for Gongbei tunnel to study the relationship between stress characteristic and thrusts magnitude. The results show that pipe stress is positively correlated to jacking force. The stress concentration of the monitored section occurs horizontally on both side of the pipe and the stress concentration is located near the pipe joint in the pipe axis direction.