从桥梁缆索的分类和结构特点入手,分析了损伤桥梁缆索的主要因素,列举了常见的针对桥梁缆索的防护手段,进而引出了一种新型环保的防护手段(材料)——喷涂聚脲,并对其应用优势进行了相关说明.并结合实施案例阐述了喷涂聚脲在相关领域的具体使用方法以及优良的防护性能.

采用半预聚法制备了一种新型脂肪族喷涂聚脲,讨论了其耐腐蚀、耐黄变和耐老化等性能.结果表明,该聚脲具有优良的力学性能和耐老化性能,拉伸强度≥20 MP a、断裂伸长率≥400％,人工气候老化1500 h力学性能保持率≥89％,与未老化样片相比△E≤2,臭氧老化1500 h后表面无可见裂纹,且在高密度聚乙烯(HDPE)护套表面喷涂该聚脲后能将其使用寿命延长3～4倍.

主缆作为悬索桥重要承重构件,其工作状态影响桥梁使用寿命.对悬索桥主缆主要防腐结构应用现状进行介绍,对防腐结构存在的问题进行分析,对聚脲防护性能与使用方法进行介绍,并详细阐述喷涂聚脲后悬索桥主缆防腐结构形式与特点.

High-strength steel wire is the basic unit of the cable, and the status of the wire directly determines the cable carrying capacity. Based on the study of the wire broken detection signal by using magnetostrictive guided wave testing, 150 steel wires were classified by artificial accelerated corrosion method. 30 steel wires are used as a group on a special bracket and regularly pour dilute hydrochloric acid to accelerate corrosion. According to the depth of corrosive pits, the corrosion of steel wire was divided into five grades. The signal characteristics of steel wire before and after corrosion were tested by using magnetostrictive waveguide nondestructive testing instrument. The above experiments show that perfect wire background signal reflection coefficient is below 2%(97% probability). So the detection signal can be sensitive to feedback the wire corrosion or not. However, it is difficult to evaluate corrosion degree grading by pits depth or weight loss. The non-destructive testing signal by using magnetostrictive guided wave is very complicated because of the size of pits, shape, orientation, surface distribution, weight loss and other factors. In conclusion, the research ideas and conclusions on the corrosion grading of steel wire and the non-destructive testing of magnetostrictive guided wave have a good effect on the corrosion evaluation of steel wire and its cable.

在拉索体系中设置减振器,是斜拉索振动控制的主要措施之一.本文总结桥梁拉索振动的控制目标,通过实索减振试验对剪切式高阻尼橡胶减振器的性能进行研究分析.试验结果表明,在安装剪切式高阻尼橡胶减振器后,拉索的一阶、二阶和三阶振动对数衰减率分别为4.19％、3.68％和3.43％.可见,该减振器具有较好的减振效果,适用于长度小于250m的钢丝或钢绞线拉索的振动控制.

在钢丝缺陷检测的基础上对拉索断丝磁致伸缩导波检测信号特性进行研究,通过对平行钢丝拉索制作断丝缺陷,详细分析研究不同断丝数量下导波检测信号的特性,得到缺陷回波反射系数与拉索缺陷截面损失率(即断丝根数)的关系,即断丝根数越多缺陷回波信号幅值越大,可对拉索金属承载面积进行检测,避免出现重大损失,为钢丝拉索的损伤磁致伸缩导波无损检测的工程实际应用提供了数据基础.

为满足国内外桥梁工程规范对拉索振动控制的要求,在拉索体系中设置减振器是斜拉索振动控制的主要措施之一.论文通过实索减振试验,对高阻尼橡胶减振器、剪切式高阻尼橡胶减振器和永磁式磁流变减振器三种实用的拉索减振器进行了研究,试验结果表明这三种减振器性能均能满足相关国际规范要求,高阻尼橡胶减振器一阶振动对数衰减率为1.62％适用于80 m以下的桥梁拉索减振,剪切式高阻尼橡胶减振器一阶振动对数衰减率为4.19％适用于250 m以下的桥梁拉索减振,永磁式磁流变减振器一阶振动对数衰减率为7.79％适用于大跨径桥梁拉索减振.

PDF HTML XML Export Cite reminder Reliability study of OVM250 steel strand cable-stayed anchorage system DOI: 10.59238/j.pt.2013.05.001 Author: Affiliation: (Liuzhou OVM Machinery Co., Ltd., Liuzhou 545005,China) Clc Number: U448.25 Fund Project: Article | Figures | Metrics | Reference | Related | Cited by | Materials | Comments Abstract:With the development of modern long-span cable-stayed Bridges, the on-site cable-stayed cable of steel strand has been more and more favored by designers because of its advantages such as no need for large cable-making, transportation, hoisting and tension traction equipment, and superior overall protective performance of the cable. As a load-bearing component of cable-stayed bridge, the steel strand cable-stayed cable is called the life cable of cable-stayed bridge, and its reliability is one of the key factors to determine the safety and reliability of cable-stayed bridge. This paper mainly introduces the reliability research of cable anchoring system in the process of design and improvement of OVM250 steel strand cable system. Through the design means of effectively improving the fatigue performance of cable anchoring assembly, the optimal design of cable anchoring unit is carried out to ensure the safety and reliability of cable anchoring assembly. The fatigue test of OVM250-139 cable anchoring assembly is further conducted The excellent fatigue resistance of OVM250 steel strand cable system was verified. Reference Related Cited by

随着现代大跨度斜拉桥的发展,钢绞线斜拉索采用现场制索,具有无需大型制索、运输、吊装和张拉牵引设备、拉索的整体防护性能优越等优势,已越来越受到设计者的青睐。钢绞线斜拉索作为斜拉桥的承重构件,堪称斜拉桥的生命索,其可靠性是决定斜拉桥安全可靠的关键因素之一。文章主要介绍了OVM250钢绞线斜拉索体系设计改进过程中对拉索锚固系统的可靠性研究,通过有效提高拉索锚具组件的疲劳性能的设计手段,对拉索锚固单元进行优化设计,保证拉索锚具组件的安全可靠,通过OVM250-139拉索锚具组件的疲劳试验,进一步验证了OVM250钢绞线拉索体系优异的抗疲劳性能。