基于不同湿度环境下高分子修复剂对混凝土裂缝自愈合性能的影响研究  

Research on Effect of Polymer Repair Agent on Self-Healing Performance of Concrete Cracks Based on Different Humidity Environments

作　　者：石宝存 陈景雅[1] 朱润禹 孙睿 王方伟 SHI Baocun;CHEN Jingya;ZHU Runyu;SUN Rui;WANG Fangwei(College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学土木与交通学院,南京210098

出　　处：《工业建筑》2023年第4期154-160,172,共8页Industrial Construction

基　　金：国家自然科学基金项目(52078190);教育部人文社会科学研究规划基金项目(18YJAZH119)。

摘　　要：通过检测表观形貌特征、气体渗透性、水分传输性和抗压强度的变化,系统研究了不同湿度环境下混凝土损伤劣化规律和裂缝修复机理,揭示了在不同湿度环境下环境响应型高分子修复剂对损伤混凝土自愈合的激励机制;同时,结合扫描电子显微镜、能谱分析和X射线衍射研究了裂缝自愈合的微观结构和演变机理。结果表明:自然空气和相对湿度30%的养护环境不利于混凝土裂缝的自修复行为;随着养护湿度的增加,混凝土裂缝修复率不断增大,潮湿环境有利于环境响应型高分子修复剂充分发挥激励作用,促进裂缝自愈合特性,延长服役寿命;浸水环境下高分子修复剂的修复效果最佳,裂缝愈合率可达70.38%,其耐久性和抗压强度等性能都明显优于素混凝土;裂缝愈合的主要原因是修复剂吸水膨胀,大量碳酸钙和钙矾石等凝胶沉淀物填充裂缝;混凝土裂缝自修复行为是物理变化和化学变化共同作用的结果。The damage deterioration law and crack repair mechanism of concrete under different humidity environments were systematically studied by the changes of apparent morphological characteristics,gas permeability,moisture transport and compressive strength,and the incentive mechanism of environmental responsive polymeric repair agents on the self-healing of damaged concrete under different humidity environments was revealed;meanwhile,the microstructure and evolution mechanism of crack self-healing were studied by combining scanning electron microscopy,energy spectrum analysis and X-ray diffraction.The microstructure and evolution mechanism of crack self-healing were also investigated by combining scanning electron microscopy,energy spectrum analysis and Xray diffraction.The results showed that the natural air and 30%relative humidity curing environment were not conducive to the self-healing behavior of concrete cracks;with the increase of curing humidity,the concrete crack repair rate increased continuously,and the humid environment was favorable for the environmentally responsive polymeric repair agent to give full play to the stimulating effect,promote the crack self-healing characteristics,and prolong the service life;the best repair effect of polymeric repair agent was achieved under the water immersion environment,and the crack healing rate could reach 70.38%,the durability and compressive strength of the repaired concrete were significantly better than those of plain concrete.The main reason for crack healing was that the repair agent absorbed water and swells,and a large amount of gel precipitates such as calcium carbonate and calcium alumina filled the cracks;the self-healing performance of concrete cracks was the result of both physical and chemical changes.

关 键 词：混凝土裂缝 湿度环境 干湿循环 高分子修复剂 自愈合 

分 类 号：TU528[建筑科学—建筑技术科学]