摘要
混凝土材料的裂缝产生与扩张一直是土木工程领域亟待解决的难点问题之一.论文将形状记忆合金(SMA)材料植入混凝土材料中,构成一种基于SMA驱动的智能混凝土材料.通过对SMA材料的电阻变化和混凝土裂缝大小的关系进行讨论,建立了SMA智能混凝土材料的裂缝监测理论模型;对SMA试件在初始状态为奥氏体情况下所展示的形状记忆效应进行理论和试验分析,给出了SMA智能混凝土材料的裂缝修复理论模型;最后通过试验测试,讨论了不同尺寸试件的裂缝修复过程和裂缝修复程度.论文研究可为形状记忆合金智能混凝土材料的进一步优化设计和工程应用提供理论指导.
Shape memory alloys(SMA), as one kind of smart materials, owing to their unique shape memory effect and superelasticity, have been widely used as sensors and actuators in aerospace, mechanical and biomedical applications. An important application of SMAs in civil engineering is crack monitoring and repair of concrete. The generation and expansion?of cracks in concrete materials has?always been a difficult problem to solve in the field of civil engineering. One way to realize crack monitoring and repair of concrete is using the SMA as an actuator. Therefore, in this work, the SMA smart concrete material is designed by implanting the SMA materials into the concrete materials, and the mechanism and experimental study on crack monitoring and repair of SMA smart concrete are given. First, based on the physical and mechanical properties of each material, the relationship between the change in resistance of SMA material and the crack size of concrete is discussed, and the theoretical model for crack surveillance of SMA smart?concrete material is established. Through theoretical and experimental tests, the shape memory effects of SMA under mechanical constraint and temperature loading are discussed, the restoring force of the SMA specimen?initiated by austenite is obtained, and the theoretical model for crack repair of SMA smart?concrete materials is then given. Finally, experimental tests of crack repair for the SMA smart concrete specimens of different sizes are conducted. The results show that by applying the experimental scheme designed in this work, the SMA indeed can repair cracks. However, only less than 10% of the cracks can be repaired, which cannot achieve the goal of complete repair. This paper may provide theoretical guidance for further optimization design and engineering application of SMA smart? concrete materials.
作者
张亚楠
李军超
王庆菲
刘兵飞
Yanan Zhang;Junchao Li;Qingfei Wang;Bingfei Liu(Airport College,Civil Aviation University of China,Tianjin,300300;Facultyof Aeros pace Engineering,Cirvil Ariation University of China,Tianjin,300300)
出处
《固体力学学报》
CAS
CSCD
北大核心
2020年第2期170-181,共12页
Chinese Journal of Solid Mechanics
基金
国家自然科学基金(11502284,51608522)
中央高校基金(3122015C019).
关键词
形状记忆合金
智能结构
混凝土
裂缝修复
shape memory alloy
intelligent structure
concrete
crack repair
