采用二维颗粒流软件对水泥冷再生混合料间接抗拉强度模拟  

Simulation on Indirect Tensile Strength of Cement Cold Recycling Mixtures Using Particle Flow Code of Two Dimension

作　　者：王勇生 刘延金[2] WANG Yongsheng;LIU Yanjin(Gansu Province Transportation Planning,Survey Design Institute Co.Ltd,Lanzhou 730030,China;School of Civil Engineering,Qinghai University,Qinghai 810016,China)

机构地区：[1]甘肃省交通规划勘察设计院股份有限公司,兰州730030 [2]青海大学土木工程学院,西宁810016

出　　处：《硅酸盐学报》2019年第11期1611-1620,共10页Journal of The Chinese Ceramic Society

基　　金：教育部春晖项目(Z2015030)

摘　　要：采用二维颗粒流软件(PFC2D)对水泥冷再生混合料间接抗拉强度开展模拟试验研究。为了对数值试验中细观力学参数的调整提供依据,并分析模拟试验结果的可靠性,首先对水泥冷再生混合料间接抗拉强度开展室内试验,得出宏观力学参数值。然后确定混合料中颗粒的接触本构模型,建立数值试件。进行模拟加载,不断调整细观力学参数值,直到最终模拟试验结果与室内试验结果相吻合,得出最终细观力学参数值。利用得出的细观力学参数,对不同颗粒级配条件下的试件进行模拟试验,通过与室内试验对比,验证模拟试验的可靠性。结果表明:模拟试验中应力增长曲线与室内试验结果基本吻合,数值试验中3组试件的间接抗拉强度值与室内试验实测值得平均误差仅为2.14%;所确定的接触模型和细观力学参数值是准确的,可在相关研究中用模拟试验代替室内试验,提高研究效率;模拟试验真实地展现了试件在荷载作用下内部颗粒的运移情况,揭示了材料强度形成机理和细观力学特征。The numerical simulation on the indirect tensile strength of cement cold recycling mixtures(CCRM) was carried out using particle flow code of two-dimension(PFC2 D). Firstly, taking indoor tests and obtaining the macroscopic mechanical parameters so as to compare it with numerical trials. The results can provide the basis for the adjustment of the micromechanical parameters in the simulation and verify the reliability of simulated results. A model of numerical specimen was proposed after determining contact constitutive model. The correlation between simulated and indoor test results was evaluated by constantly adjusting the values of micromechanical parameters, and determining the final parameter value. The results show that the stress growth curve in the simulation is basically consistent with the indoor test results. The average error between the indirect tensile strength values of the three groups of specimens in the simulated and measured values of the indoor test is only 2.14%. Since the identified contact model and micromechanical parameters are accurate, the simulated results can be used instead of partial lab-scale experiment. The simulated results can show the motion of particles during the process and reveal the strength formation mechanism and micromechanical characteristics of CCRM.

关 键 词：水泥冷再生混合料 颗粒流理论 数值试验 间接抗拉强度 细观力学参数 

分 类 号：U414[交通运输工程—道路与铁道工程]