不同纤维掺量再生混凝土骨料轻质混凝土性能研究  

Study on performance of lightweight concrete with recycled concrete aggregate with different fiber content

作　　者：张培恒 韩尚宇[1] 康登源 王先蓉 张慧华[1] ZHANG Peiheng;HAN Shangyu;KANG Dengyuan;WANG Xianrong;ZHANG Huihua(School of Civil Engineering and Architecture,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]南昌航空大学土木建筑学院,江西南昌330063

出　　处：《混凝土》2024年第6期99-104,共6页Concrete

基　　金：国家自然科学基金(52068054);南昌航空大学研究生创新专项资金立项项目(YC2021-S700)。

摘　　要：为了研究聚丙烯(PP)纤维增强再生混凝土骨料轻质混凝土的性能,以普通硅酸盐水泥、再生废弃混凝土粗骨料、聚丙烯纤维、泡沫为主要材料,选取PP纤维掺量为变量,对试样进行室内试验研究。结果表明:随PP纤维掺量增加,浆体流动度呈下降趋势;当采用再生粗骨料级配(即粒径为9.5~16 mm、16~19 mm、19~26.5 mm、26.5~31.5 mm、31.5~37.5 mm的5类骨料的质量比)为2∶4∶8∶3∶3和30%体积率时,建议浆体流动度大于210 mm;试件抗压强度和劈裂抗拉强度随PP纤维掺量的增加均呈先增大后减小趋势,说明PP纤维对再生混凝土骨料轻质混凝土性能提升效果有限;PP纤维的掺入会使再生混凝土骨料轻质混凝土材料早期抗压强度和劈裂抗拉强度形成速度降低;当纤维掺量由0增大为0.2%时,增加了孔隙率,降低了平均孔径。The properties of polypropylene(PP)fiber-reinforced recycled lightweight concrete with recycled concrete as aggregates(RCLC)was experimentally studied.The RCLC was mainly prepared by ordinary Portland cement,recycled waste concrete coarse aggregate,PP fiber and foam.By taking the content of PP fiber as a variable,the RCLC samples were tested in laboratory.The results showed that the flowability of slurry decreased with the increase of PP fiber dosages.When the gradation of recycled coarse aggregate(i.e.,the mass ratio of five-type aggregates sized,respectively,from 9.5 mm to 16 mm,from 16 mm to 19 mm,from 19 mm to 26.5 mm,from 26.5 mm to 31.5 mm and from 31.5 mm to 37.5 mm)is 2∶4∶8∶3∶3 and the volume ratio of aggregates takes 30%,it is recommended that the slurry fluidity should be greater than 210 mm.The compressive strength and splitting tensile strength of the specimens increased first and then decreased with the increase of the content of PP fiber,which indicated that PP fiber has limited effect on improving the performance of RCLC.Besides,the addition of PP fiber will reduce the early compressive strength and splitting tensile strength.Further,when the fiber content increased from 0 to 0.2%,the porosity increased and the average pore diameter decreased.

关 键 词：聚丙烯纤维 再生粗骨料 轻质混凝土 力学性能 孔结构 

分 类 号：TU528.041[建筑科学—建筑技术科学]