泥质砂岩地层盾构隧道管片连续上浮规律与分析

Law and analysis of continuous floating of shield tunnel segments in argillaceous sandstone stratum

为了得到施工期盾构隧道管片的连续上浮规律,基于连通器原理设计一套管片竖向位移连续监测装置,依托华东某泥质砂岩地层盾构隧道进行现场实测研究。研究结果表明:管片在脱出盾尾前12 h内呈现出“阶梯状”上浮的规律,即上浮主要发生在盾构掘进期间,而在待机期间管片上浮趋势逐渐减缓,直至停止上浮。最大上浮速率可达0.2 cm/min,主要发生在掘进期间,最大下降速率为0.15 cm/min。管片上浮增量与时间仅呈中等相关或弱相关的关系,而与所处的位置呈强相关或极强相关的关系。掘进期间,上浮增量累计占比为76.9%,是待机期间的3.3倍。

To obtain the continuous floating law of shield tunnel segments during construction,a set of continuous monitoring devices for segment vertical displacement were designed based on the principle of connector.The field measurements were carried out based on a shield tunnel in an argillaceous sandstone stratum in East China.The results show that the segments exhibit a"ladder"floating law within 12 h after detaching the shield tail,meaning that segment floating mainly occur during shield tunneling state,while in standby state,the segment floating to slows down gradually until they stop.The maximum floating rate reaches 0.2 cm/min,which mainly occurs during shield tunneling,and the maximum falling rate is 0.15 cm/min.The floating increment of the segment only moderately or weakly correlated with time but strongly or extremely strongly correlated with position.The cumulative proportion of floating increment during tunneling is 76.9%,which is 3.3 times that of standby state.