The equivalent bolt stiffness is key to the circumferential design of shield tunnels. The three-dimensional refined model was established to calculate deviation of bolt stiffness between actual situation and equivalent joint as well as the correction stiffness coefficientη was proposed. Then, the influencing factors of the stiffness correction coefficient were explored and the correction formula of bolt equivalent stiffness was put forward, which was used for the typical engineering calculations. The results indicate that indispensable error appears during the longitudinal bending calculation when equivalent homogeneous bolt represents the actual joints of shield tunnels. The type of bolts change the joint stiffness, which makes the maximum error of stiffness correction coefficient reach 10.5%. The influence of bolt quantity on equivalent stiffness is obvious, and the correction coefficient increase linearly with increasing quantity of bolts. Outside disturbance has little impact on equivalent bolt stiffness when disturbance level is low and does not increase the error caused by equivalent stiffness. The displacement error of the typical engineering example are respectively 9.6% and 31.9% deviation from measurements with and without correction considered , respectively, so the correction calculation method of equivalent bolt stiffness is more reasonable.%管片环向接头等效刚度是盾构隧道纵向设计的关键参数.为此,建立盾构管片三维精细数值模型,计算分析等效接头刚度与实际螺栓接头刚度的偏差,引入等效刚度修正系数η;探讨刚度修正系数的影响因素,提出等效刚度修正计算公式,并应用于工程实例.研究结果表明:盾构隧道纵向计算中用等效螺栓环表征实际接头存有不容忽视的误差;螺栓型式影响实际点状分布接头刚度,导致不同螺栓型式等效刚度最大相差10.5%;螺栓数量对等效刚度影响明显,等效刚度随实际螺栓数量的增加近似线性增大;外部扰动水平不高时,对刚度等效影响很小,不会放大螺栓刚度等效引起的误差;实例计算中等效刚度修正前后位移计算结果与实测值误差分别为31.9%和9.6%,说明接头等效刚度修正计算方法更具合理性.
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