摘要
掌握水下盾构隧道运营期结构正常响应规律是进行结构异常响应预警的前提。基于武汉长江隧道健康监测系统,首次获得了长期运营过程中(2013-2020年)管片应变监测数据,系统研究了应变增量分布规律、应变增量与温度增量和水位增量的关联关系、以及相邻管片应变增量空间的关联关系,提出了基于应变增量的结构异常响应预警方法并确定了相应的预警阈值。研究结果表明:(1)正常运营期应变增量分布尾部比正态分布更重,指数分布可以较好地描述应变增量绝对值的分布规律;(2)应变增量难以预测,但是其变化范围可以通过统计分析确定,据此可提出一种结构异常响应单测点预警方法并确定其预警阈值;(3)正常运营期间,相邻管片应变增量存在一种“你胀我缩”的变形模式,使得相邻管片平均应变增量能被约束在一个相对较小的变化范围,据此可提出一种结构异常响应多测点联合预警方法并确定其预警阈值。
The structural abnormal response of underwater shield tunnel under operation is the prerequisite of structural abnormality early warning.Based on the monitoring segment strains of typical sections of the Wuhan Yangtze River tunnel during normal operation period(2013–2020),the distributions of strain increments,the relations of strain increment with temperature increment and water level increment,and relations of strain increments between adjacent segments(i.e.spatial effects)are thoroughly studied.An early warning method of structural abnormal response based on strain increment is proposed and the corresponding early warning threshold value is determined.Study results show that:1)The distribution of strain increments does not obey the normal distribution but has a fat-tail.The exponential distribution can be used to describe the distribution of the absolute value of the strain increment.2)The temporal strain increment is difficult to predict,but its variation range can be well determined through statistical analysis.Thus,an early warning method for structural abnormality is proposed based on the monitoring strain increment of a single measuring point,and its threshold value is determined.3)There is a deformation mode of"one expand,the other contract"between adjacent segments during normal operation,which means the strain increases of one segment but decreases of the adjacent segment.This spatial effect constraints the average strain increments of adjacent segments in a relatively small variation range.Thus,another early warning method can be developed based on the monitoring strain increments of several adjacent measuring points,and its threshold value is determined.
作者
杨建平
王琛
黄煜诚
秦川
陈卫忠
YANG Jian-ping;WANG Chen;HUANG Yu-cheng;QIN Chuan;CHEN Wei-zhong(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;General Contracting Branch of China Communications Construction Corporation Limited,Beijing 100088,China;Wuhan Yangtze River Tunnel Construction Co.,Ltd.,Wuhan,Hubei 430062,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2022年第8期2253-2262,共10页
Rock and Soil Mechanics
基金
国家自然科学基金(No.U1806226,No.51991392)
中国科学院重点部署项目(No.22ZDRW-ZS-2021-3)
中国科学院青年创新促进会。
关键词
盾构隧道
结构健康监测
管片应变
统计方法
预警
阈值
shield tunnel
structural health monitoring
segment strain
statistic method
early warning
threshold value
