高温后纤维增强全再生粗骨料混凝土力学性能试验研究  

Experimental study on mechanical properties of fiber reinforced total recycled coarse aggregate concrete after high temperature

作　　者：梁莹 刘丁瑗 周济 苏炜炜 陈宗平 LIANG Ying;LIU Dingyuan;ZHOU Ji;SU Weiwei;CHEN Zongping(College of Architecture and Civil Engineering,Nanning University,Nanning 530200,China;College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Guangxi University,Nanning 530004,China)

机构地区：[1]南宁学院土木与建筑工程学院,广西南宁530200 [2]广西大学土木建筑工程学院,广西南宁530004 [3]广西大学工程防灾与结构安全教育部重点试验室,广西南宁530004

出　　处：《混凝土》2024年第10期84-90,共7页Concrete

基　　金：国家自然科学基金(51578163);广西高校中青年教师科研基础能力提升项目(2024KY1885);八桂学者专项(桂政发【2019】79);南宁市科学研究与技术开发计划重大项目(20223024);广西重点研发计划项目(桂科AB21220012);广西科技基地和人才专项项目(桂科AD21075031)。

摘　　要：为研究高温后纤维增强全再生粗骨料混凝土力学性能,以历经最高温度、混杂纤维类型、纤维掺量为变化参数,设计并完成了44个试件的轴压试验,观察了高温后试件的表观变化及受力破坏形态,获取了荷载-位移曲线,分析了各变化参数对试件破坏形态、质量烧失率、峰值荷载和峰值变形的影响规律。结果表明:随历经最高温度升高,纤维全再生粗骨料混凝土表观由青灰色变淡红色,最后呈淡褐色,其质量烧失率近似呈线性增长;随温度的升高,试件破坏开裂时间越早,表观损伤越严重,而随钢纤维、玄武岩纤维掺量增加,试件裂缝发展减缓,整体性更好;试验范围内,掺钢-玄武岩纤维试件的峰值荷载随钢纤维掺量增加而减小,随玄武岩纤维掺量增加而增大,其峰值变形随两类纤维掺量的增加均表现为先增后减;对掺钢-聚丙烯纤维试件,随钢纤维掺量增加,峰值荷载先减后增,峰值变形增大,随聚丙烯纤维掺量增加,峰值荷载减小,峰值变形先减后增。In order to study the mechanical properties of fiber reinforced total recycled coarse aggregate concrete after high temperature,the axial compression tests of 44 specimens were designed and completed with the maximum temperature,hybrid fiber type and fiber content as the change parameters.The apparent change and failure mode of specimens after high temperature were observed,and the load-displacement curve was obtained.The influence of various parameters on the failure mode,mass loss rate,peak load and peak deformation of specimens was analyzed.The results show that with the increase of the maximum temperature,the apparent color of fiber recycled coarse aggregate concrete changes from grey to light red,and finally shows light brown,and the mass loss rate increases approximately linearly.With the increase of temperature,the earlier the specimen cracks,the more serious the apparent damage.With the increase of steel fiber and basalt fiber content,the crack development of the specimen slows down and the integrity is better.Within the test range,the peak load of steel-basalt fiber specimens decreases with the increase of steel fiber content,and increases with the increase of basalt fiber content.With the increase of the content of steel fiber or polypropylene fiber,the peak deformation first increases and then decreases.For steel-polypropylene fiber specimens,with the increase of steel fiber content,the peak load decreases first and then increases,and the peak deformation increases.With the increase of polypropylene fiber content,the peak load decreases,and the peak deformation decreases first and then increases.

关 键 词：高温 混杂纤维 再生粗骨料 混凝土 力学性能 

分 类 号：TU528.041[建筑科学—建筑技术科学]