港珠澳大桥桥塔与吊具连接高强螺栓群受力分析

Force Analysis of High-Strength Bolt Group Connecting Pylon and Hoisting Device of Hong Kong-Zhuhai-Macao Bridge

为了解港珠澳大桥江海直达船航道桥风帆型桥塔吊装过程中桥塔与吊具连接高强螺栓群的受力状况,提出较为合理的桥塔吊装连接方案,以该桥桥塔Z10号节段吊装连接为例进行分析。采用ANSYS建立桥塔Z10号节段及吊具有限元模型,取0°、45°和90°3种典型吊装模态对高强螺栓群进行受力分析。结果表明:在水平至垂向吊装过程中,吊臂与桥塔采用高强螺栓群连接,满足不了吊装要求。为此,采取用高强度钢拉杆组件替换部分受力过大的高强螺栓等措施加强吊具与桥塔连接的可靠性。采取加强措施后高强度钢拉杆最大拉应力为947MPa、径向剪应力为586MPa;高强螺栓群最大拉应力为829 MPa、径向剪应力为395 MPa,均满足吊装要求,该方案已得到成功应用。

To have an understanding of the force conditions of the high-strength bolt group connecting the sail-shape pylon and hoisting device in the process of hoisting and installing the pylon of the River-to-Sea Ship Channel Bridge of the Hong Kong-Zhuhai-Macao Bridge, the appropriate scheme for hoisting and installing the pylon and for connecting the pylon and hoisting device was proposed. The hoisting and installing of segment Z10 of the pylon of the bridge was cited as a case analysis. The ANSYS was used to set up the finite element model for both the segment Zl0 and the hoisting device, 3 typical hoisting and installing modes of 0°, 45° and 90° were selected and the force conditions of the high-strength bolt group were analyzed. The results of the analysis show that in the hoisting and installing of the pylon from the horizontal to the vertical directions, the pylon and hoisting boom connected by the high-strength bolt group can not cater for the requirements of the hoisting and installing. In such case, the measure of replacing part of the high- strength bolts that are to bear excessive load with the high-strength steel rod assembly is taken in order to enhance the reliability of the connecting of the pylon and hoisting device. With the measure having been taken, the maximum tensile stress of the steel rods is 947 MPa and the radial shear stress is 586 MPa. The maximum tensile stress of the high-strength bolt group is 829 MPa and the radial shear stress is 395 MPa. The stresses all can satisfy the requirements and the proposed scheme is finally successfully put in use in the construction.