摘要
为了将废弃混凝土破碎分离再生粗骨料,提出了一种利用水射流技术破碎混凝土分离粗骨料的新方法,开展了水射流破碎混凝土分离粗骨料的数值模拟及试验研究,探究了不同射流压力下再生粗骨料的基本性质、二维形态、三维形态、粒形特征及再生混凝土抗压强度。结果表明,相较于机械方式,水射流再生粗骨料的残余粘附砂浆含量和针片状含量分别降低了53%和68%,表观密度提升了1.7%、空隙率和吸水率分别降低了3%和41%,可以达到Ⅰ类国家标准;水射流冲击对粗骨料的破碎程度在可接受范围内,再生粗骨料对比天然粗骨料,平均粒径仅下降约7%;将再生粗骨料分别以30%,40%,50%的量掺入再生骨料混凝土试件时,水射流再生粗骨料混凝土相比于传统机械再生粗骨料混凝土,其抗压强度分别提高了5.8%,22.7%,17.7%。研究可为水射流在混凝土破碎再利用方面的应用提供理论依据。
In order to crush and separate the recycled coarse aggregate(RCA)from the waste concrete(WC),a new method of crushing the concrete and separating the coarse aggregate by using water jet technology was proposed,and the numerical simulation and experimental research on the separation of coarse aggregate from the crushed concrete by water jet were carried out,and the basic properties,2D and 3D morphology,particle shape characteristics and compressive strength of RCA under different jet pressures were explored.The results show that,compared with the mechanical method,the residual adhesion mortar content and needle flake content of water jet RCA are reduced by 53%and 68%,the apparent density is increased by 1.7%,and the porosity and water absorption rate are reduced by 3%and 41%,respectively,which can reach Class I in the national standard.The crushing degree of coarse aggregate by water jet impact is within the acceptable range,and the average particle size of RCA is only about 7%lower than that of natural coarse aggregate.When the RCA is mixed into the recycled aggregate concrete specimen at 30%,40%and 50%respectively,the compressive strength of the waterjet RCA concrete is increased by 5.8%,22.7%and 17.7%respectively compared with the traditional mechanical RCA concrete.This study can provide a theoretical basis for the application of water jet in concrete crushing and reuse.
作者
王泽峰
李雅诗
蒋宇涛
潘超
唐杰
WANG Zefeng;LI Yashi;JIANG Yutao;PAN Chao;TANG Jie(School of Urban Construction,Wuhan University of Science and Technology,Wuhan 430065,China;Hubei Provincial Engineering Research Center for Urban Renewal,Wuhan University of Science and Technology,Wuhan 430065,China;Institute of High Performance Engineering Structures,Wuhan University of Science and Technology,Wuhan 430065,China;China Construction Third Bureau,First Engineering Co.,Ltd.,Wuhan 430040,China)
出处
《流体机械》
CSCD
北大核心
2024年第12期31-38,共8页
Fluid Machinery
基金
湖北省重点研发计划项目(2023BCB044)
国家自然科学基金项目(52108169)
武汉科技大学“十四五”湖北省优势特色学科(群)项目(2023D0503,2023D0501)
湖北省建设科技计划项目(2022070)。
关键词
废弃混凝土
高压水射流
粗骨料分离
再生粗骨料
waste concrete
high-pressure water jets
coarse aggregate separation
recycled coarse aggregate
