本文以国内首条矩形盾构隧道工程为背景，对矩形盾构衬砌结构在整个施工期的荷载及结构响应进行现场追踪测试，探索衬砌结构在施工期的主要受力阶段、结构外荷载及其响应随时间的变化规律，以全面掌握矩形盾构隧道衬砌结构在施工期的受力行为。研究结果表明：1）衬砌结构在施工期的受力可划分为自重阶段、脱出盾尾阶段、同步注浆阶段和稳定荷载阶段；2）脱出盾尾阶段和同步注浆阶段的结构外荷载分别为稳定荷载阶段的1．5～3．0倍和1．5～2．5倍，为衬砌结构在施工期的2个不利受力阶段；3）稳定荷载阶段的结构外荷载及其分布与理论计算较为吻合；4）衬砌结构在施工期的内力基本满足左右对称，内力分布特征与运营阶段基本一致。%The field monitoring test on loading and response of lining structure of a rectangular shield tunnel is carried out;the main loading stages,external load and response of lining structure are discussed,so as to learn the mechanical behavior of lining structure of rectangular shield tunnel during construction.The test results show that:1 )The loading of lining structure during construction can be divided into 4 stages,i.e.dead weight stage,shield tail passed stage, synchronous grouting stage and load stabilizing stage.2 )The load of lining structure in shield tail passed stage and synchronous grouting stage are 1.5 -3.0 and 1.5 -2.5 time that in load stabilizing stage respectively.3)The external load and its distribution rules of lining structure in load stabilizing stage coincide with theoretical calculation results.4) The internal force of lining structure during construction is bilaterally symmetry;and the distribution characteristics of internal force during construction coincide with those during operation.
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