废砖和废混凝土粗骨料再生混凝土配合比研究  

Study on the mix proportion of recycled concrete with waste brick and waste concrete coarse aggregate

作　　者：张鹏[1] 张博 邓宇[1] 陈思远 郝宇茜 郭镇 ZHANG Peng;ZHANG Bo;DENG Yu;CHEN Siyuan;HAO Yuxi;GUO Zhen(School of Civil Engineering and Architecture,Guangxi University of Science and Technology,Liuzhou 545006,China)

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006

出　　处：《广西科技大学学报》2023年第2期30-37,共8页Journal of Guangxi University of Science and Technology

基　　金：国家自然科学基金项目(52168016,51768008)资助。

摘　　要：为探究一种以废砖和废混凝土制成粗骨料的再生混凝土配合比,以再生粗骨料完全替代天然粗骨料,通过改变再生粗骨料的取代率,设计了6种再生混凝土配合比;制备了再生粗骨料和36个再生混凝土试块,并测定试块的抗压强度;分析了再生粗骨料的物理性能、新拌混凝土的和易性,以及试块破坏形态及力学性能。试验结果表明:1)再生混凝土在固定水胶比下引入附加用水量可使得新拌混凝土具有较好的和易性,能够满足新拌混凝土的拌制、运输和浇筑要求;2)废砖再生粗骨料占比较高时,主要因废砖再生粗骨料的压溃破坏导致试块破坏,占比较低时,主要因粗骨料与水泥的黏结破坏而破坏;3)再生混凝土试块的抗压强度随着废砖粗骨料取代率的增加呈下降趋势,6种配合比的再生混凝土试块立方体抗压强度在水灰比为0.43的情况下均能达到25 MPa以上。In order to explore the mix proportion of a recycled concrete with coarse aggregate made of waste bricks and waste concrete,and to completely replace natural coarse aggregate with recycled coarse aggregate,six recycled concrete mix proportions were designed by changing the replacement rate of recycled coarse aggregate.The recycled coarse aggregate and 36 recycled concrete test blocks were prepared.And the compressive strength of the test blocks was measured respectively.The physical properties of the recycled coarse aggregate,the workability of the fresh concrete,the failure morphology and mechanical properties of test blocks were analyzed.The test results show that adding water to recycled concrete at a fixed water binder ratio can make fresh concrete have good workability and meet the requirements of mixing,transportation and pouring of fresh concrete;When the proportion of recycled coarse aggregate of waste bricks is high,the crushing failure of recycled coarse aggregate of waste bricks will lead to the destruction of test blocks;when the proportion is low,the bonding failure of coarse aggregate and cement will lead to the destruction;The compressive strength of recycled concrete test block decreases with the increase of replacement rate of coarse aggregate of waste brick;The compressive strength of the cube of recycled concrete test blocks with 6 mix proportions can reach more than 25 MPa when the water cement ratio is 0.43.

关 键 词：再生混凝土 配合比 废砖 废混凝土 再生粗骨料 抗压强度 

分 类 号：TU528.04[建筑科学—建筑技术科学]