基于主成分分析的物理整形对再生粗骨料形貌特征影响的研究  

Influence of physical shaping on morphological characteristics of recycled coarse aggregates based on principal component analysis

作　　者：申景涛 黄新宇 马昆林[1] 谢友均[1] 龙广成[1] 胡明文 SHEN Jingtao;HUANG xinyu;MA Kunlin;XIE Youjun;LONG Guangcheng;HU Mingwen(School of Civil Engineering,Central South University,Changsha 410075,China;China Railway Urban Construction Group Co.,Ltd.,Changsha 410208,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中铁城建集团有限公司,湖南长沙410208

出　　处：《铁道科学与工程学报》2025年第3期1112-1120,共9页Journal of Railway Science and Engineering

基　　金：长沙市科技计划重点研发项目(kh2005213);中铁城建集团有限公司科技计划项目(2023-1A)。

摘　　要：物理整形是再生粗骨料强化的重要方法之一。为了综合评价物理整形对再生粗骨料形态特征的影响,为再生粗骨料的制备及高品质利用提供研究基础,研究了物理整形对再生粗骨料物理性能的影响。通过集料图像测量系统(AIMS)采集不同整形时间的再生粗骨料典型形态特征参数,基于主成分分析方法将圆度、球度、细长度和扁平度组合成了整体形态因子,将棱角度、粗糙度和分形维数组合成表面形态因子,分析整形对再生粗骨料的形态特征的影响。研究结果表明:物理整形显著降低了再生粗骨料的空隙率、吸水率和压碎指标,改善了再生粗骨料性能。随着物理整形时间增加,再生粗骨料的整体形态因子增大,而表面形态因子先降低后增大。再生粗骨料的整体形态因子增大,则粗骨料的整体形状趋于球形,粗骨料的堆积密实程度越好,整体形态因子的增大是堆积空隙率降低的主要原因;表面形态因子降低,则粗骨料表面形态越规则。物理整形使再生粗骨料的整体形态较天然粗骨料更近似于球形,但不能使再生粗骨料表面形态比天然粗骨料更规则,且随整形时间延长,再生粗骨料可能发生二次破碎使颗粒表面更不规则,从而造成表面形态因子增大。通过物理整形强化再生粗骨料时,可根据粗骨料表面形态因子的变化来合理控制整形时间。Physical shaping(PS)is an important method for strengthening recycled coarse aggregates(RCA).In order to further evaluate the influence of PS on the morphology characteristics of RCA and provide basic research for the production,preparation and high-quality utilization of RCA,the influence of PS on the physical properties of RCA was studied.The typical morphological parameters of the RCA at different PS time was investigated by aggregate image measurement system(AIMS).Based on principal component analysis method,circularity,sphericity,elongation ratio and flatness ratio were combined into integral morphological factor,and angularity,texture and fractal dimension were combined into surface morphological factor.Results show that PS can significantly reduce the voidage,water absorption and crushing index of RCA,and improve the properties of RCA.With the increase of PS time,the integral morphological factor increases,and the surface morphological factor decreases first and then increases.When the integral morphological factor of RCA increases,the shape of RCA tends to be more spherical,and the packing density of aggregate is good.The increase of the integral morphological factor is the main reason for packing voidage decreasing.With the decrease of surface morphological factor,the surface morphology of RCA tends to be regular more and more.PS makes the integral shape of RCA more spherical than that of natural aggregate but cannot make the surface shape of RCA more regular than natural aggregate.Moreover,with the increase time of PS,RCA can be broken more than once to lead to the surface of the RCA more irregular,resulting in the surface morphological factor increasing.Therefore,it is suggested that the PS time should be adjusted by the change of surface morphological factor of RCA.

关 键 词：再生粗骨料 物理整形 形态特征 主成分分析 

分 类 号：TU528[建筑科学—建筑技术科学]