洪都大桥索夹抗滑试验研究  

Experimental Study of Slip Resistance of Cable Clamps of Hongdu Bridge

作　　者：赵承新[1,2] 严敏兰 张安户[1,2] 魏洋[4] 王甫胜[4] 

机构地区：[1]中铁大桥局集团桥科院有限公司,湖北武汉430034 [2]桥梁结构安全与健康湖北省重点实验室,湖北武汉430034 [3]武汉市建设学校,湖北武汉430051 [4]南京林业大学土木工程学院,江苏南京210037

出　　处：《世界桥梁》2013年第1期64-68,共5页World Bridges

摘　　要：为了解自锚式悬索桥索夹的实际抗滑性能,以洪都大桥为背景,采用足尺模型试验和实体有限元分析相结合的方法研究自锚式悬索桥索夹螺栓轴力衰减规律、索夹应力分布及抗滑摩阻系数。结果表明:螺栓轴力衰减先快后慢,螺栓最终的有效轴力约为设计轴力的80%;索夹内应力均从加载端到索夹末端逐渐减小,滑移推力工况下索夹最大应力普遍大于设计推力工况下的,在螺栓轴力偏大位置索夹应力也较大,说明索夹内摩阻力沿主缆轴线并非完全呈理想的线性分布;实测索夹抗滑摩阻系数为0.25,比规范建议值0.15偏大,实测值偏安全。建议施工时按先两端后中间且对角施拧的顺序施拧螺栓,控制各螺栓紧固力的一致性,并在关键工况前进行重复施拧。In order to understand the actual slip resistant performance of the cable clamps of self-anchored suspension bridges, the Hongdu Bridge was cited as an example. A method of the combination of full scale model test and finite element analysis for the real bridge was taken to study the attenuation law of the bolt axial force, stress distribution and anti-slip friction coeffi- cient of the cable clamps of the self-anchored suspension bridge. The results of the analysis indi- cated that the attenuation of bolt axial force was fast at the beginning stage, and then gradually became slow, the final effective axial force of the bolt was about 80 % of the design axial force; the inner stress in each cable clamp gradually diminished from the point where the load was ap-plied to the end of the cable clamp; the maximum stress in the cable clamp under the action of slip thrust was generally greater than that under the action of design thrust. The greater bolt axial force gave rise to the greater cable clamp stress in the corresponding location, which implied that the inner friction force of the cable clamp along the axial line of the main cable did not follow the law of ideal linear distribution. The measured anti-slip friction coefficient of the cable clamp was 0.25, greater than the value of 0.15 suggested in the code, and the measured value was relatively safe. It is advised that in the construction, the bolt be tightened from the two ends towards the center and by the way of diagonal tightening, the uniformity of the tightening force for the bolts should be controlled, and the bolts be repeatedly tightened before each critical operation.

关 键 词：悬索桥 索夹 摩阻系数 抗滑试验 有限元法 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U446.1[交通运输工程—道路与铁道工程]