深埋软土盾构输水隧洞管片内力反演分析  

Inverse Analysis of Internal Forces in Shield Tunnel Segments for Water Conveyance in Deep-Buried Soft Soil

作　　者：谢春蔚 付俊峰[1] 王超 董家兴[1] XIE Chun-wei;FU Jun-feng;WANG Chao;DONG Jia-xing(Faculty of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,China;PowerChina Kunming Engineering Corporation Limited,Kunming 650051,China)

机构地区：[1]昆明理工大学电力工程学院,云南昆明650500 [2]中国电建集团昆明勘测设计研究院有限公司,云南昆明650051

出　　处：《水电能源科学》2024年第12期111-115,共5页Water Resources and Power

摘　　要：依托滇中引水工程盾构隧洞监测试验环,于掘进方向进口和出口埋设两排混凝土应变计,同时埋设钢筋计作为对照组,对试验环的内力分布情况进行了现场试验监测。依据所获取的大量现场监测数据,分析了监测试验环混凝土应变与钢筋应变的误差、反演管片内力及其变化规律和内力安全性。结果表明,钢筋应变大于等于混凝土应变,受盾构机盾尾作用面的影响,进口处的钢筋应变与混凝土应变误差明显小于出口处;拱顶和拱底受较小正弯矩的作用,两侧受负弯矩作用,轴力值表现出持续的增长趋势且F块轴力明显大于其余块管片,F型管片部位整体性较差,是受力薄弱点,应尽量避免将F块布置到拱肩处;内力均在1.3的安全系数包络图内,表明该环结构适用于此处地质条件。Leveraging the shield tunnel's test ring within the Dianzhong water diversion project,two rows of concrete strain gauges were embedded at the entrance and exit in the excavation direction.Additionally,reinforcing bars were em-bedded as a control group.On-site experimental monitoring was conducted to analyze the internal force distribution of the test ring.Based on the extensive on-site monitoring data,the study investigated the strain discrepancy between concrete and steel reinforcement in the monitored test ring and performed an inverse calculation of internal forces in the tunnel lin-ing segments.The analysis included variations and safety assessments of internal forces.The results indicate that the steel reinforcement strain is greater than or equal to concrete strain.Influenced by the shield tail effect,the discrepancy between steel reinforcement strain and concrete strain at the entrance is significantly smaller than at the exit.The arch top and bottom experience small positive bending moments,while the sides are subjected to negative bending moments.The axial force values show a continuous increasing trend,and the axial force in the F-type segment is significantly greater than in other segments,indicating structural weakness in the F-type segment,avoid placing block F on the spandrel as much as possible.The internal forces are within the enveloping diagram of a safety factor of 1.3,indicating that the structure is suitable for the geological conditions of this test ring.

关 键 词：盾构隧洞 现场试验监测 应变误差 反演内力 

分 类 号：TV672.1[水利工程—水利水电工程] U455.46[建筑科学—桥梁与隧道工程]