废弃轻质混凝土可控低强材料的制备及性能评价  

Preparation and performance evaluation of controlled low-strength materials incorporating waste lightweight concrete

作　　者：林峰[1] LIN Feng(China Railway Fourth Survey and Design Institute Group Co.,Ltd.,Wuhan 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430063

出　　处：《混凝土》2023年第4期188-191,共4页Concrete

摘　　要：为解决市政道路管道、沟槽等回填工程中因结构死角存在而回填不密实问题,提出以废弃轻质混凝土为细骨料制备一种高流动性的可控低强度材料(CLSM)。研究水泥和粉煤灰比例(C/F)及机制砂掺量对该CLSM的工作性能和力学性能的影响。试验结果表明:直接利用机制砂以0~20%等质量取代废弃轻质混凝土细骨料,通过调节C/F比和机制砂掺量,可制得流动度在202~311 mm、泌水率<3%的高流动度、可自密实的CLSM,且C/F在0.4~0.5的范围内强度满足可再开挖要求。To solve the problem of incomplete backfilling due to the existence of structural dead angle in the backfilling engineering of municipal road pipes and trenches,a kind of high fluiditycontrolled low-strength material(CLSM)is prepared by using waste lightweight concrete as fine aggregate.The effects of cement/fly ash ratio(C/F)and machine-made sand content on the working and mechanical properties of CLSM are studied.The experimental results show that by directly replacing the waste lightweight concrete fine aggregate with the mass of 0~20%machine-made sand,and by adjusting the C/F ratio and the content of machine-made sand,the controlled low-strength material with high fluidity and self-compacting can be prepared with the fluidity of 202~311 mm,bleeding rate of 0~2.1%.And the strength of C/F in the range of 0.4~0.5 meets the requirements of re-excavation.

关 键 词：可控低强度材料 废弃轻质混凝土 机制砂 流动度 抗压强度 

分 类 号：TU528.01[建筑科学—建筑技术科学]