再生砖细骨料形态对混凝土流变行为与力学性能的影响  

Effect of Morphology of Recycled Fine Aggregate from Clay Bricks on Rheology Behavior and Mechanical Properties of Concrete

作　　者：党钧陶 刘耘池 肖建庄[2] 李风兰 杨金龙 DANG Juntao;LIU Yunchi;XIAO Jianzhuang;LI Fenglan;YANG Jinlong(School of Civil Engineering and Communication,North China University of Water Resources and Electric Power,Zhengzhou 450045,China;College of Civil Engineering,Tongji University,Shanghai 200092,China;International Joint Research Lab for Eco-building Materials and Engineering of Henan,North China University of Water Resources and Electric Power,Zhengzhou 450045,China)

机构地区：[1]华北水利水电大学土木与交通学院,河南郑州450045 [2]同济大学土木工程学院,上海200092 [3]华北水利水电大学河南省生态建材工程国际联合实验室,河南郑州450045

出　　处：《建筑材料学报》2024年第7期629-636,共8页Journal of Building Materials

基　　金：国家自然科学基金资助项目(52208247)。

摘　　要：评价了再生砖细骨料(RFCB)的几何形状和表面形态,研究了RFCB颗粒级配和初始饱水度对混凝土流变行为与力学性能的影响.结果表明:相比天然河砂,RFCB几何形状不规则且形状参数较低,表面形态呈凹陷凸起状且粗糙度较大;RFCB复杂的物理特性导致新拌混凝土的屈服应力与塑性黏度增大,劈裂抗拉强度有所提高且对抗压强度无较大不利影响;适当降低RFCB的最小粒径和初始饱水度,虽会使混凝土的流变性能变差,但有助于在混凝土中形成以再生砖细骨料为软核、界面为硬壳的结构,从而提高了混凝土的力学性能.The geometrical shape and surface morphology of recycled fine aggregate from clay brick(RFCB)were assessed,and the influence of particle size distribution and initial water saturation of RFCB on the rheology behavior and mechanical properties of concrete was explored.The results indicate that compared to natural river sand,the geometrical shape of RFCB shows irregular shape as well as lower morphological index,and the surface morphology of RFCB exhibites undulation topography with concave and convex as well as higher roughness value.Due to the complexity of physical characteristics of RFCB,both the yield stress and plastic viscosity of fresh concrete are increased,and the splitting tensile strength of hardened concrete is enhanced,but it has no significantly adverse effect on the compressive strength.Optimally reducing the minimum particle size and initial water saturation of RFCB result in a poor rheological behavior of fresh concrete,but it helps in forming soft core of inner RFCB and stiff shell of outer interface,thus enhances the mechanical properties.

关 键 词：再生砖细骨料 再生混凝土 几何形状 表面形态 流变行为 力学性能 

分 类 号：TU528.01[建筑科学—建筑技术科学]