考虑静荷载与环境耦合作用的钢结构涂层劣化实验研究  

Experimental Study of Steel Structure Coating Deterioration Considering Coupling Effect of Static Load and Environment

作　　者：戚彦福 蔺鹏臻[1] 李岩 潘亚磊 QI Yanfu;LIN Pengzhen;LI Yan;PAN Yalei(Key Laboratory of Road&Bridge and Underground Engineering of Gansu Province,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学甘肃省道路桥梁与地下工程重点实验室,兰州730070

出　　处：《材料导报》2024年第18期161-170,共10页Materials Reports

基　　金：国家自然科学基金重大项目(11790281);甘肃省交通运输厅科研项目(2020-08)。

摘　　要：为研究钢结构涂层在静荷载与大温差、风沙侵蚀作用下的劣化性能,设计了钢结构涂层的静荷载加载系统;以钢桥常见的普通型和长效型体系为对象,通过静力加载与温差控制、气流挟沙喷射法开展实验研究。采用拉开法测试了静荷载与大温差耦合作用下涂层的劣化情况,并对涂层的附着、内聚破坏模式进行定量化测试;结合拉开法及厚度测试结果,得到了涂层抗力的动态劣化过程;采用气流挟沙喷射法研究了静荷载与大温差作用下涂层的耐冲蚀性能,综合实验结果,得到涂层在静荷载与环境耦合作用下工作性能的退化过程。研究结果表明:静荷载与环境耦合作用使面漆抗力衰减至防护功能破坏后,大温差导致涂层材料向脆性转变,静荷载加速涂层的劣化,风沙冲蚀作用造成涂层从体系剥离;耦合作用下体系的抗力快速衰减,涂层逐次退出工作,涂装体系完全丧失抗力,最终从基材上剥离。对于实验涂装体系,经历30 d静荷载与大温差作用后,涂层附着力最大降低8.97%,厚度、冲蚀量、临界冲蚀角最大分别增加25.3%、46.15%、17.4%。In order to study the deterioration performance of steel structure coating under the static load,temperature variation and sandstorm erosion,a static loading system for steel structure coating specimen was designed.Then the experiment research was carried out on the conventional and durable coating system of steel bridges by static loading,temperature control and the airflow spray method.The degradation of coatings under the coupling action of static load and temperature variation were tested by the pull-of test,and the coating damage modes of adhesion and cohesive were quantitatively measured.Combined with pull-of test and thickness measurement results,the dynamic deterioration process of coating resistance was obtained.The erosion resistance of coatings under the static load and temperature variation was studied by the airflow spray method,and the degradation process of coatings working performance under the coupling action of static load and environment was obtained based on the experimental results.The results show that the coupling effect of static load and environment makes the resistance of topcoat attenuate until its protective function is destroyed,the temperature variation causes coating materials transform to brittle materials,static load accelerates the dete-rioration rate of coating,and sandstorm erosion is going to strip coatings from the system.Then the coatings are deactivated successively since the coupling action cause the recession of system resistance,the coating system completely loses resistance and eventually peels off from the substrate.For the experimental coating systems,after 30 d of static load and temperature variation,the adhesion of coating decreased by 8.97%,the thickness,erosion amount and critical erosion angle increased by 25.3%,46.15%and 17.4%,respectively.

关 键 词：钢结构涂层 静荷载 大温差 风沙冲蚀 劣化机理 试验研究 

分 类 号：TU593[建筑科学—建筑技术科学]