聚乙烯醇纤维高强再生混凝土梁抗弯性能研究  

Study on flexural behavior of high-strength recycled aggregate concrete beams with polyvinyl alcohol fiber

作　　者：牛海成[1] 高锦龙 李国利 尚天宇 黄明晖 NIU Haicheng;GAO Jinlong;LI Guoli;SHANG Tianyu;HUANG Minghui(School of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China;The Second Construction Limited Company of China Construction Eighth Engineering Division,Jinan 25ooo0,Shandong,China;Henan XingJian Engineering Consulting Co.,Ltd,Pindingshan 467000,Henan,China)

机构地区：[1]河南理工大学土木工程学院,河南焦作454000 [2]中建八局第二建设有限公司,山东济南250000 [3]河南兴建工程咨询有限公司,河南平顶山467000

出　　处：《实验力学》2023年第5期634-644,共11页Journal of Experimental Mechanics

基　　金：国家自然科学基金项目(U1904188);河南省自然科学基金项目(182300410247);河南理工大学博士基金项目(B2016-66)。

摘　　要：为研究聚乙烯醇纤维对高强再生混凝土梁抗弯性能的影响,以混凝土类型和聚乙烯醇纤维体积掺量为变化参数,通过5根试件的抗弯试验观察各试件表面裂缝发展情况和破坏特征,得到了各试件荷载-应变曲线和荷载-最大裂缝宽度曲线,并分析了不同参数对抗弯性能的影响。试验结果表明:各试验梁应变变化均符合平截面假定;再生混凝土梁开裂荷载比普通混凝土梁小,抗弯刚度和变形能力较差;掺入聚乙烯醇纤维可有效抑制裂缝的产生与快速发展,亦显著提高了再生混凝土梁的开裂荷载和抗弯刚度,增强了变形能力;与未掺入纤维的再生混凝土梁相比,当聚乙烯醇纤维体积掺量为0.2%时,开裂弯矩、初始刚度和延性系数分别提高了59.4%、15.2%和17.4%。基于试验数据,文中提出了聚乙烯醇纤维再生混凝土梁裂缝宽度计算公式,通过计算结果可知,计算值和实测值吻合较好。To study the influence of the polyvinyl alcohol fiber on flexural performance of highstrength recycled concrete beams,the type of concrete and the volume content of polyvinyl alcohol fiber are used as the changing parameters.5 specimens were completed to bending load test.The development of surface cracks and failure modes of specimens were observed.The load-strain curves and load-maximum crack width curves of the specimens were obtained.The influence of different parameters on its bending performance is analyzed.The experimental results show that the crosssection strain distribution conforms to the assumption of flat section.Compared with ordinary concrete beams,recycled concrete beams have small cracking load,poor bending stiffness and deformation ability.The addition of polyvinyl alcohol fiber inhibits the occurrence and rapid development of cracks,and also significantly improves the cracking load and bending stiffness of recycled concrete beams;in addition,polyvinyl alcohol fiber also enhances the deformation capacity of recycled concrete beams.Compared with recycled aggregate concrete beams without fiber,when O.2% polyvinyl alcohol fiber was added,the cracking moment,initial stiffness and ductility coefficient are increased by 59.4%,15.2% and 17.4% respectively.Based on the experimental data,the formula for calculating the maximum crack width of polyvinyl alcohol fiber recycled concrete beams is put forward.The calculation results show that the calculated values are in good agreement with the measured values.

关 键 词：聚乙烯醇纤维 再生混凝土梁 开裂弯矩 延性 抗弯性能 

分 类 号：TU375.1[建筑科学—结构工程]