二元粗集料间隙率形成规律与机制研究  

Study on the formation law and mechanism of VCA of binary coarse aggregates

作　　者：代金国 王炘 苗超 许百巧 刘树堂 DAI Jin-guo;WANG Xin;MIAO Chao;XU Bai-qiao;LIU Shu-tang(Highway Administration of Weifang City,Weifang 261041,China;Qingzhou Hongda Highway Engineering Limited Liability Company,Qingzhou 261000,China;Shandong Metallurgical Design Institute Limited Liability Company,Jinan 250101,China;School of Qilu Transportation,Shandong University,Jinan 250002,China)

机构地区：[1]潍坊市公路事业发展中心,山东潍坊261041 [2]青州鸿达公路工程有限责任公司,山东青州261000 [3]山东省冶金设计院股份有限公司,山东济南250101 [4]山东大学齐鲁交通学院,山东济南250002

出　　处：《长沙理工大学学报（自然科学版）》2020年第1期23-31,共9页Journal of Changsha University of Science and Technology:Natural Science

基　　金：山东省自然科学基金资助项目(ZR2013EEM028)。

摘　　要：为了研究二元粗集料间隙率形成的规律与机制,将A(19~31.5 mm)、B(13.2~19 mm)、C(9.5~13.2 mm)及D(4.75~9.5 mm)4档规格的石灰岩粗集料进行两两组合,获得6种二元粗集料,通过振实试验得到各二元粗集料的间隙率。试验结果表明:二元粗集料的间隙率随着粗集料加入量的增多呈现凹形曲线变化,存在一谷值。但各凹形曲线变化的速率与谷值不同,粗集料与较细粗集料的几何平均粒径比越大,曲线变化速率越大,谷值越低。通过回归分析,建立了各二元粗集料间隙率的有效统计模型。提出了填充效应系数的概念,以反映较细粗集料对较粗粗集料的填充程度,并建立了填充效应系数与粗集料几何平均粒径比的有效统计线性关系式。线性关系式表明:粗细集料粒径差距越大,即粒径比越大,较细粗集料对较粗粗集料的填充效果越好,即二元粗集料的间隙率越小。在此基础上建立了二元粗集料统一回归模型,揭示了二元粗集料间隙率的形成机制。In order to study the formation law and mechanism of Voids in Coarse Aggregates(VCA)of binary coarse aggregates,the limestone coarse aggregates in grades A(19-31.5 mm),B(13.2-19 mm),C(9.5-13.2 mm)and D(4.75-9.5 mm)were combined in pairs to obtain 6 kinds of binary mixtures.The results of VCA of binary mixtures were obtained through vibration experiments.The experimental results showed that the VCA-values of binary aggregates presented concave curve with the increase of the amount of bigger size coarse aggregates,and there were valley values.But the changing rates of concave curves and valley values were different.With the increase of the ratio of geometric mean particle diameter between smaller coarse aggregates and coarse aggregates,the rate of concave curve changed more and the valley value was lower.By means of regression analysis,several effective statistical models of VCA of binary mixtures were established and a concept called filling effect coefficient was proposed to reflect the degree of smaller coarse aggregates filling in coarse aggregates.An effective statistical linear relationship between the filling effect coefficient and the ratio of geometric mean particle diameter was built,which showed that the size difference between smaller coarse aggregates and coarse aggregates was more,i.e.the ratio of geometric mean particle diameter was bigger,the effect of smaller coarse aggregates filling in coarse aggregates was better and VCA-value of binary mixtures was smaller.On those basis a unified regression model of binary mixtures was built and the formation mechanism of VCA of binary mixtures was revealed.

关 键 词：道路工程 二元粗集料 粗集料间隙率 粗集料几何平均粒径比 有效统计模型 

分 类 号：U416.217[交通运输工程—道路与铁道工程]