某地锚式边缆多次张拉人行悬索桥施工控制及分析

CONSTRUCTION CONTROL AND ANALYSIS OF A GROUND ANCHORED PEDESTRIAN SUSPENSION BRIDGE WITH SIDE CABLES REPEATEDLY TENSIONED

依托某地锚式人行悬索桥实例工程,对该人行悬索桥的主塔、主梁、主缆的应力及变形进行监测控制,使主塔、主梁、主缆的实际内力分布与设计理想的内力状态一致。并应用Midas/Civil有限元分析软件对该人行悬索桥的施工过程进行实时检测。监测控制结果显示,人行悬索桥桥面标高相差最大的位置均为30#吊杆断面处,最大差值为B点0.8cm,其次是A、C点均为0.5cm;成桥时主缆标高测点差值为0.7cm;结构在施工过程中应力理论最大值为-2.6MPa,实测应力值和理论应力值差值很小,理论值和实测值最大差值为0.3MPa,有限元计算、设计要求与桥梁在施工进程中体现出来的应力结果基本符合,结构的应力状态良好;成桥状态时边缆的实测索力与设计索力相差最大仅为-1.8%;在整个施工过程中主塔始终处于安全状态。监测控制结果满足整体规范要求。

The stress and deformation of the main tower, main beam and main cable of a ground anchored pedestrian suspension bridge are monitored and controlled by a case project, so that the actual internal force distribution of the main tower, main beam and main cable is consistent with the ideal internal force state of the design. Midas/Civil finite element analysis software is used to detect the construction process of the pedestrian suspension bridge in real time. The monitoring and control results show that the positions with the largest elevation difference of pedestrian suspension bridge is the section of 30#derrick, and the maximum difference is 0.8 cm at point B, followed by 0.5 cm at point A and C. When the bridge is completed, the difference of elevation measurement point of the main cable is0.7 cm. In the construction process, the maximum theoretical stress value is-2.6 MPa, the difference between the measured stress value and the theoretical stress value is verysmall, and the maximum difference between the theoretical value and the measured value is 0.3 MPa. The finite element calculation and design requirements are basically in line with the stress results reflected in the construction process of the bridge, and the stress state of the structure is good. The difference between the measured cable force and the designed cable force is only-1.8%when the bridge is completed. The main tower is always in a safe state during the whole construction process. Monitoring and control results meet the overall specification requirements.