【摘要】 某城市高架桥为4×25m空心板梁桥,桥墩为直径1.4m的柱式桥墩。由于不平衡堆土导致桥墩出现较大的横向位移,为顺利对桥墩进行适量纠偏,确保结构受力合理、安全,以横向位移为控制目标,对桥墩纠偏过程进行施工监控。采用MIDAS GTS软件建立桥墩、桩和土有限元模型,计算得到满足结构安全性条件下桥墩最大偏位为88mm;在施工应力释放孔、旋喷桩以及横向顶推过程中,在盖梁或防撞墙上安装位移计监测桥墩横向位移和左右幅梁间距,在桥墩上安装倾角仪监测桥墩倾角。控制结果表明:旋喷桩纠偏作用明显,桥墩在旋喷桩产生的压力作用下逐渐回位;横向顶推过程中,持荷期间桥墩缓慢回位;纠偏后各墩最大偏位均小于88mm,结构处于安全状态。更多还原

【Abstract】 A city viaduct is a hollow slab beam bridge with span arrangement of 4×25m.The piers are the columned piers with a diameter of 1.4m.Due to the unbalanced soil pile,great transverse displacement was found on the piers.To make proper offsetting rectification for the piers and ensure the rational and safe load bearing behavior of the structure,the transverse displacement was taken as the control objective to monitor the offsetting rectification process of the piers.The MIDAS GTS software was used to establish the finite element models of the piers and the pier-soil interaction.According to the calculation,the maximum offsetting is 88 mm,which meets the requirements of structural safety.During the construction of the stress dissipating holes and churning piles and the transverse pushing,displacement monitoring gauges were installed on the cap beam or the collision protection walls to monitor the transverse displacement of the piers and the space between the left and right decks.Inclinometers were installed on the piers to monitor the inclination angle of the piers.The results of the control results indicate that churning piles are quite effective in rectifying offsetting,piers gradually returns to their original position under the action of stress caused by the churning piles.During the transverse pushing process,the piers slowly moves back to their original position during the load holding period.After the offsetting rectification,the maximum offsetting of each pier is less than 88 mm,and the structure remains in safe condition.更多还原