沉管隧道节段接头剪力分配原则及降低剪力构造措施研究

Shear distribution principle and measures for reducing shear structure of segmental joints in immersed tunnel

以港珠澳大桥沉管隧道工程为背景,首先利用有限元软件建立节段式沉管隧道三维模型,通过数值计算研究横向均匀地基刚度条件下节段接头剪力分担比及横向不均匀地基刚度系数对剪力键剪力分配影响,随后通过室内模型试验进行了验证。研究结果表明:横向均匀地基刚度条件下剪力键平均分担剪力,单个剪力键剪力变化值与横向不均匀地基刚度系数成正比;设置弹性垫层是降低节段接头剪力的有效措施,可降低剪力10%~20%。

Based on the background of the Hongkong-Zhuhai-Macao Bridge immersed tunnel project,firstly we establishedthe3D model of the immersed tunnel by finite element software,carried out numerical simulation to study the shear forcesharing ratio of segmental joint under the condition of uniform lateral foundation stiffness,and studied the influence ofnonuniform lateral foundation stiffness coefficient on shear distribution of shear connectors,then verified the above research byindoor model.The results show that under the condition of uniform lateral foundation stiffness,shear force can be evenlydistributed to shear connectors;shear force of a single shear connectors is proportional to the coefficient value of nonuniformlateral foundation stiffness;the elastic cushion is an effective measure to reduce the shear force of the segmental joint,whichcan reduce the shear force by10%to20%.