内蒙古中西部大温差强紫外环境下钢结构涂层受风沙侵蚀损伤机理研究

This research is continuation and supplement of the completed NSFC project named “Study of Erosion Mechanical Behavior and Evaluation on Surface Coating of Steel Structure in Sandstorm”. The western and central region of Inner Mongolia is located in the severe cold areas and intensive ultraviolet environment, it is also the high activity region of sandstorm. The coating of steel structure in this region was seriously eroded by long-term compound effects in special natural environment, which results in the decline of its durability and safety. The research background of this project is based on the intensive ultraviolet, severe cold and sandstorm environment of this region, and the research object is the polyurethane coating that is widely used in steel structure. Damage rules about mechanics and resistance to environmental aging properties of the coating will be discovered through the corrosion tests that coating are corroded under single and combined actions of intensive ultraviolet environment and high-low temperature cycles; The erosion simulation system of sandstorm is utilized to study the erosion of the coating which is corroded by intensive ultraviolet environment and high-low temperature cycles, and the inner relationship between the erosion weight loss and different erosion-mechanical parameters will be studied. With the combination of digital image correlation experiment method, the Hertz contact theory analysis and finite element simulation, the mechanics behaviors and damage mechanism of the coating will be studied. Based on the similarity theory, the equal conversion relationship between the test results and the actual working conditions will be analyzed. The results of the research will provide a basis for the design, application and protection of the coating of steel structure in this region.

本项目是已结题国家基金项目《风沙环境下钢结构涂层侵蚀力学行为及损伤评价研究》的延续和补充。内蒙古中西部地处严寒区和强紫外环境，且是风沙高活动区域，特殊区域自然环境长期复合作用对在该地区钢结构表面涂层造成严重侵蚀，使其耐久性和安全性下降。本项目以该地区强紫外、严寒和风沙特殊区域自然环境为研究背景，以在钢结构中广泛应用的聚氨酯涂层为研究对象，通过对钢结构涂层在强紫外辐射和高低温循环的单一和双重因素复合作用侵蚀试验，探明其力学和耐环境老化性能的损伤规律；利用模拟风沙环境侵蚀实验系统对受强紫外和高低温循环侵蚀前后的涂层进行冲蚀试验，研究其冲蚀磨损量与不同冲蚀力学参数的内在关系；应用数字图像相关方法，结合Hertz接触理论和有限元模拟研究涂层在侵蚀前后受风沙冲蚀的力学行为与损伤机理；并基于相似理论分析涂层受风沙侵蚀试验结果与实际工况的等效换算关系。研究结果将为钢结构涂层的设计、应用和防护提供依据。

内蒙古中西部地处严寒区和强紫外环境，且是风沙高活动区域，特殊区域自然环境长期复合作用对在该地区钢结构表面涂层造成严重侵蚀，使其耐久性和安全性下降。本项目基于该地区环境特征与实际工程背景，研究钢结构聚氨酯涂层在紫外光照射和高低温循环作用下的侵蚀失效过程，以及其侵蚀前后受风沙冲蚀的力学行为及损伤机理。经过多年系统研究，取得重要结果：分析总结出内蒙古中西部地区紫外辐照、严寒气候和风沙环境特征；测得了钢结构聚氨酯涂层基本力学性能；通过对钢结构聚氨酯涂层进行紫外和高低温循环的单一和双重因素复合作用侵蚀试验，研究其力学性能和耐环境老化性能的损伤失效过程与损伤机理；利用模拟风沙环境侵蚀实验系统对受紫外辐射和高低温循环的单一和双重因素复合作用侵蚀前后的涂层进行风沙环境冲蚀试验，应用扫描电镜和激光共聚焦显微镜分析其冲蚀损伤微观形貌特征及损伤机理；利用自动球压冲击仪对钢结构聚氨酯涂层进行冲击试验，通过数字图像相关实验得到冲击荷载作用下的变形场和应变场分布规律，结合Hertz接触理论和Abaqus数值模拟研究出其受冲击荷载作用下的弹塑性变形特征和应力场分布规律。利用相似理论分析了风沙侵蚀试验结果与实际工况的等效对应换算关系。另就钢结构防护涂层（改性氧化石墨烯/聚氨酯涂层）进行研制和基本力学性能测试，研究了改性氧化石墨烯/聚氨酯涂层耐风沙冲蚀性能和冲击损伤性能。研究结果可为该地区钢结构防护涂层的设计、应用和防护提供依据。受本项目资助，相关研究结果发表（录用）学术论文12篇，其中被EI检索8篇，高质量期刊T1级5篇、T2级1篇、T3级3篇；研制出科研仪器设备2套，获发明专利1项，实用新型1项、软著4项。.此外，通过项目资助，加强了研究团队建设，培养博士生2人、硕士生10人(毕业8人、在读2人)。项目负责人获自治区青年创新人才奖、自治区青年科技奖，入选了自治区草原英才、自治区高校青年科技领军人才。