（北京交通大学土木建筑工程学院， 北京 100044）

［摘要］以实际工程为背景，通过结构精细化建模，在索穹顶结构中建立多根环索，研究索穹顶结构的静力性能及环索内力分布规律。对使用荷载状态下的环索，提出系统的建模方法，进行环索弯曲工况的数值模拟分析，得到环索控制截面索丝应力的不均匀分布规律。同时考虑初始应力比、弯曲角度以及索丝不同层数等因素，对弯曲工况下的环索进行参数化分析，研究环索应力不均匀分布的规律。研究结果表明：在使用荷载状态下，环索内力从内到外均匀增加； 弯曲工况下索丝应力不均匀分布现象相对于直拉工况更加显著，故弯曲工况下应将环索初应力放大1.7～2倍； 环索截面不均匀程度随索力增加而减弱，随索丝层数增加而增强，环索应力不均匀性随弯曲角度增加而增加。

［关键词］索穹顶结构； 环索； 建模方法； 弯曲工况； 应力分布规律； 参数化分析

中图分类号：TU312，  TU318文献标识码：A文章编号：1002-848X(2020)23-0051-07

Stress distribution law of ring cable wires at cable pinch node in cable dome structure

YANG Weiguo, WANG Ya, WANG Xin, WANG Meng, LIU Pei

(School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China)

Abstract:Taking actual engineering as the background, multiple ring cables in the cable dome structure were established according to the refined structural modeling. The static force performance of the cable dome structure and the inner force distribution law of the ring cable were researched. Under applied load, the system modeling method was proposed to simulate the cable bending condition and the stress uneven distribution law of cable wire in the control section of ring cable was obtained. Parameterization analysis was studied considering the initial stress ratio, bending angle and the number of different layers of cable wire, and the stress uneven distribution law of ring cable. The results show that: under applied load, the internal force of the ring cable increases evenly from inside to outside; under bending condition, the stress uneven distribution of cable wire is more significant than that of cable wire under straight condition, so the initial stress of ring cable should be enlarged by 1.7～2 times; the inhomogeneity of ring cable section decreases with the increase of cable force and increases with the increase of cable wring layer, the stress inhomogeneity of ring cable increases with the increase of bending angle.

Keywords:cable dome structure; ring cable； modeling method; bending condition; stress distribution law; parameterization analysis

*国家自然科学基金（51578046）。

作者简介：杨维国，教授，博士生导师， Email: wgyang1@bjtu.edu.cn； 通信作者：王亚，博士研究生，Email: wangya_73@163.com。