摘要
针对紧接盾构隧道或盾构穿切桩基工程中附加外力作用下的盾构隧道纵向非均匀变形和受力问题,利用计算解析方法,将盾构隧道视为置于Pasternak双参数地基上的铁摩辛柯梁,同时引入修正等效连续化模型和传递矩阵法,提出一种新的盾构隧道纵向变形计算模型,并采用室内模型试验的方法进行验证。结果表明:模型试验中,在集中荷载与围压共同作用下,整个隧道处于弹性变形阶段,各环管片收敛变形、拱顶和拱底竖向位移、环缝错台量均随集中荷载的增加而近似线性增大,并以集中荷载为中心沿纵向呈对称分布,变形趋势与计算结果相同,且2种方法下环缝错台量最大相对误差仅为8.75%;2种方法得到的结果在分布特征和量值上基本一致,验证了计算模型的可行性。该计算模型能够反映土弹簧间的剪切作用、收敛变形对隧道纵向变形刚度的影响及接头的非连续性,可对盾构隧道纵向变形和内力进行预测分析,并为紧接盾构隧道工程中既有盾构隧道的安全评估提供理论指导。
In order to solve the problem of longitudinal non-uniform deformation and stress of shield tunnel under additional external forces in the engineering of immediate shield tunnel or shield tunnel piercing through pile foundation,a new calculation model for longitudinal deformation of shield tunnel is proposed by using a computational analytic method to consider shield tunnel as Timoshenko beam placed on Pasternak twoparameter foundation,and introduce the modified equivalent continuum model and transfer matrix method,which is verified by the method of laboratory model test.The results show that in the model test,under the combined action of concentrated load and confining pressure,during the whole elastic deformation stage of the tunnel,the convergence deformation of each ring segment,the vertical displacement of the arch crown and arch bottom,and the misalignment of the circumferential seam all increase approximately linearly with the increase of concentrated load,and they are distributed symmetrically along the longitudinal direction with the concentrated load as the center,whose deformation trend is the same as the calculation result.With the two methods,the maximum relative error of circumferential seam misalignment is only 8.75%.The results obtained by two methods are basically consistent in terms of distribution characteristics and magnitude,which verifies the feasibility of the calculation model.The model can reflect the shear action between soil springs,the influence of convergence deformation on longitudinal deformation stiffness of tunnel and discontinuity of joint.It can predict and analyze the longitudinal deformation and internal force of shield tunnel,and provide theoretical guidance for the safety evaluation of the existing shield tunnel in the immediate shield tunnel engineering.
作者
李明宇
朱康康
陈健
蔺云宏
吴龙骥
靳军伟
杨潇
LI Mingyu;ZHU Kangkang;CHEN Jian;LIN Yunhong;WU Longji;JIN Junwei;YANG Xiao(School of Civil Engineering,Zhengzhou University,Zhengzhou Henan 450001,China;China Railway 14th Bureau Group Corporation Limited,Jinan Shandong 250101,China;China Railway Construction Underwater Shield Engineering Laboratory,Jinan Shandong 250101,China;Guangzhou Metro Design and Research Institute Co.,Ltd.,Guangzhou Guangdong 510010,China;Wuhan Metro Group Co.,Ltd.,Wuhan Hubei 430070,China)
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2024年第1期142-154,共13页
China Railway Science
基金
泰山产业领军人才工程专项经费资助项目(tscx202306015)
河南省重点研发与推广专项(科技攻关)项目(202102310586,232102241011)
河南省住房城乡建设科技计划项目(K1940,K1817)
中铁十四局集团有限公司科技研发计划课题(9137000016305598912021A02)。
