带顶升机构前支点挂篮斜拉索初张拉中间索力的确定方法  

Method for determining the initial tensioning cable-stayed middle cable-force using travelling carriage of fore-fulcra with lifting mechanism

作　　者：张玉平[1] 胡火全 李传习[1] 刁先觉 

机构地区：[1]长沙理工大学土木与建筑学院,湖南长沙410004 [2]中交路桥华南工程有限公司,广东中山528403

出　　处：《长沙理工大学学报（自然科学版）》2016年第2期54-59,共6页Journal of Changsha University of Science and Technology:Natural Science

基　　金：科技部"973"计划项目(2015CB05772);国家自然科学基金资助项目(51378080);长沙理工大学土木工程优势特色重点学科创新性项目(15ZDXK02)

摘　　要：针对带顶升机构前支点挂篮的构造和受力特点,基于其受力图示的静力平衡条件,建立了斜拉索初张拉中间索力的3个计算公式。通过对带顶升机构的前支点挂篮各锚固和支撑位置反力极值的讨论,确定了3组斜拉索中间索力的取值范围。考虑到施工误差可能会导致挂篮各约束位置反力的变化,为保证结构安全,确定同时满足以上3组取值范围最大值和最小值的平均值为斜拉索初张拉的中间索力,之后即可结合桥梁结构整体计算确定的斜拉索初张力和已确定的中间索力对挂篮结构进行有限元验算分析。实桥算例验证表明,该方法简单可行,可供同类桥梁的施工及其施工控制参考借鉴。Aiming to the construction feature and stress characteristics of fore-fulcra travel- ling carriage with lifting mechanism, based on the static equilibrium conditions of its force diagram, three formulas of the initial tensioning cable-stayed middle cable-force are estab- lished. Through discussion of each anchor and support positions against the extreme force of fore-fulcra travelling carriage with lifting mechanism, the range of three groups of middle cable-stayed cable forces are determined. In order to ensure the safety of structure, the force which is determined to simultaneously satisfy mean values in the range of the above three groups of maximum and minimum is the middle cable force of the initial tension cable- stayed because construction error may lead to change of constrained position reaction. Travelling carriage of fore-fulcra is checked according to the middle cable-force and initial tensio- ning which is determined through the integral structural calculation of the bridges. The bridge example shows that the method is simple and feasible, and could be used for reference for construction and construction control of similar bridges.

关 键 词：斜拉桥 前支点挂篮 静力平衡条件 中间索力 

分 类 号：U445.38[建筑科学—桥梁与隧道工程]