基于残余砂浆附着特征的再生混凝土硫酸盐传输模型  

Sulfate Ion Transfer Model of Recycled Concrete Based on the Characterization of Attached Mortar

作　　者：关博文[1,2] 张硕文 吴佳育[1,2,3] 王发平 陈晓堃 GUAN Bowen;ZHANG Shuowen;WU Jiayu;WANG Faping;CHEN Xiaokun(School of Materials Science and Engineering,Chang’an University,Xi’an 710061,China;Engineering Research Center of Transportation Pavement Materials,Ministry of Education,Chang’an University,Xi’an 710061,China;School of Civil and Transportation Engineering,Ningbo University of Technology,Ningbo 315016,Zhejiang,China;Qinghai Communications Holding Group Co.,Ltd.,Xining 810000,China;Qinghai Provincial Traffic Control Construction Engineering Group Co.,Ltd.,Xining 810000,China)

机构地区：[1]长安大学材料科学与工程学院,西安710061 [2]长安大学交通铺面材料教育部工程研究中心,西安710061 [3]宁波工程学院建筑与交通工程学院,浙江宁波315016 [4]青海省交通控股集团有限公司,西宁810000 [5]青海省交控建设工程集团有限公司,西宁810000

出　　处：《材料导报》2024年第15期160-167,共8页Materials Reports

基　　金：青海省自然科学基金(2021-ZJ-765)。

摘　　要：已有再生混凝土计算模型未充分考虑残余砂浆附着特征,导致模型中缺少新砂浆-原生骨料界面过渡区,道路工程混凝土硫酸盐传输模型与实际情况不符。本工作根据瓦拉文公式将三维骨料体积转换为二维平面圆形,并根据图像分析法测得的残余砂浆附着特征将不同粒径的骨料分割成残余砂浆和裸露骨料两部分,随后利用蒙特卡罗方程将分割后的再生骨料于混凝土体系中随机投放,构建了再生混凝土的六相数字化模型。通过再生骨料截面面积确定、再生骨料数据库建立等过程,提出六相混凝土数字化模型中再生骨料残余砂浆附着特征的表达方法。基于Fick第二定律,结合孔隙率对再生混凝土中各相扩散系数的影响分析,提出再生混凝土中各相扩散系数方程。通过有限元软件实现了六相再生混凝土的二维可视化,建立了六相再生混凝土硫酸根离子传输模型。通过将试验测试值与模型计算值进行对比,得出试验结果与计算结果总体吻合度良好,理论计算结果与实验所测离子传输深度的变化规律是一致的,建立的基于残余砂浆附着特征的再生混凝土硫酸盐传输模型具有一定的合理性。The existing model of recycled concrete did not fully consider the characteristics of attached mortar,resulting in the lack of the new mortar-aggregate interface transition zone in the model,and the sulfate transfer model was inconsistent with the actual situation.In this work,the volume of the three-dimensional aggregate was converted into a two-dimensional plane circle according to the Valerian formula,and the aggregates are divided into two parts,the attached mortar and the aggregate according to the characteristics of the attached mortar measured by the image analysis method.Using Monte Carlo equations,the divided recycled aggregates were randomly put into the concrete system,and a six-phase digital model of recycled concrete was established.Through the process of determining the cross-sectional area of recycled aggregate and establishing the recycled aggregate database,a method for expressing the adhesion characteristics of the attached mortar of recycled aggregate in the six-phase concrete digital model was proposed.Based on Fick’s second law,combined with the analysis of the influence of porosity on the diffusion coefficient of each phase in recycled concrete,the diffusion coefficient equation of each phase in recycled concrete was proposed.The two-dimensional visualization of six-phase recycled concrete was realized by finite element software,and the sulfate ion transport model of six-phase recycled concrete was established.Comparing the experimental test value with the model calculation value,it is concluded that the test result is in good agreement with the calculation result.The theoretical calculation result is consistent with the change of the ion transmission depth measured in the experiment.The sulfate transport model of recycled concrete based on the adhesion characteristics of attached mortar is reasonable.

关 键 词：道路工程 再生混凝土 残余砂浆 覆盖率 硫酸根离子 模型 

分 类 号：U414[交通运输工程—道路与铁道工程]