大跨悬拼钢筋混凝土拱桥施工索力计算分析  

Calculation and analysis of construction cable force of long-span cantilever reinforced concrete arch bridge

作　　者：余钱华 李威 张家琪 YU Qianhua;LI Wei;ZHA Jiaqi(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《交通科学与工程》2022年第2期45-53,共9页Journal of Transport Science and Engineering

摘　　要：为避免大跨悬臂拼装钢筋混凝土拱桥施工过程中主拱圈出现较大的拉应力,以净跨径195 m的牛路河特大桥为依托,推导出一种施工索力优化的计算方法。在桥梁结构中,通过Midas/Civil软件进行正装分析,提取施工过程中的应力影响矩阵。根据拱肋关键截面的应力控制条件,正装计算确定扣索力的可行域,选取可行域上、下限的平均值作为扣索力初值来计算,确定最优施工扣索力。基于水平力相等的原则,确定锚索力。研究结果表明:扣索施工索力值较为均匀,拱肋施工过程中截面拉应力不超过1.5 MPa,压应力不超过7.0 MPa,混凝土拱桥施工过程中扣、锚索只需张拉一次就可计算出截面应力,提高了工作效率,可为类似工程施工提供借鉴。To avoid the large tensile stress ocurring in the main arch ring during the construction of long-span cantilever assembled reinforced concrete arch bridge,based on the Niuluhe Bridge with a net span of 195 m,an optimization calculation method of construction cable force was derived.The formal analysis was carried out in the general bridge structure analysis software Midas/Civil and the stress influence matrix in the construction process was extracted.According to the stress control conditions of the key section of the arch rib,the feasible region of the buckle force was determined by the formal calculation,and then the average value of the upper and lower limits of the feasible region were selected as the initial value of the buckle force,which was substituted into the iterative equation to determine the optimal construction buckle force,and then the anchor force was determined based on the principle of equal horizontal force.The results of numerical examples show that the cable force value of buckle cable construction is relatively uniform,the tensile stress in cross-section is less than1.5MPa and the compressive stress less than 7.0 MPa during the construction of arch rib.The stress in cross-section can be calculated when the buckle and anchor cable are be tensioned once.This improves the work efficiency and can provide reference for the construction of similar projects.

关 键 词：桥梁工程 钢筋混凝土拱桥 索力优化 可行域 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]