考虑异形孔的泡沫混凝土单轴压缩离散元模拟  

Discrete element simulation of foam concrete under uniaxial compression considering non-spherical pores

作　　者：周程涛 陈波[1,2] 高志涵 陈家林 陈锴 ZHOU Chengtao;CHEN Bo;GAO Zhihan;CHEN Jialin;CHEN Kai(State Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210098,China;College of Waterconservancy and Hydropower,Hohai University,Nanjing 210098,China;Large Dam Safety Supervision Center,National Energy Administration,Hangzhou 311122,China;Power China Huadong Engineering Corporation Limited,Hangzhou 311122,China)

机构地区：[1]河海大学水灾害防御全国重点实验室,南京210098 [2]河海大学水利水电学院,南京210098 [3]国家能源局大坝安全监察中心,杭州311122 [4]中国电建集团华东勘测设计研究院有限公司,杭州311122

出　　处：《复合材料学报》2024年第7期3726-3736,共11页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金面上项目(52079049);国家重点实验室基本科研业务费(522012272,5230248A2)。

摘　　要：为了研究异形孔隙对泡沫混凝土单轴压缩特性的影响,本文对密度等级500 kg/m^(3)的泡沫混凝土开展了X射线计算机断层扫描(X-CT)试验及单轴压缩-声发射联合试验,基于实测孔结构特征建立了不同非球形颗粒占比的三维细观离散元模型并模拟了单轴压缩过程。结果表明:离散元模型模拟的单轴压缩损伤过程与声发射试验结果基本一致,具有明显的阶段特征;异形颗粒离散元模型能表征初步密实阶段应力-应变曲线的振荡,模拟出应力消散阶段基质的剪切和互锁,在建立泡沫混凝土离散元模型时,应考虑孔隙形状的影响;离散元模型的抗压强度随模型中孔隙非球形率的提高而线性衰减,相关系数达0.94。In order to study the fitness of discrete element method(DEM)in the simulation of mechanical properties of foam concrete and the influence of non-spherical pores on the uniaxial compression characteristics of foam concrete,X-ray computed tomography(X-CT)test and uniaxial compression-acoustic emission joint test were carried out on foamed concrete with density of 500 kg/m^(3).Based on the measured pore structure characteristics,a series of three-dimensional mesoscopic DEM models with different non-spherical particle proportions were established and the uniaxial compression process was simulated.The results show that the uniaxial compression damage process of the model is basically consistent with the acoustic emission test results,which has obvious stage characteristics.The non-spherical particle discrete element model can characterize the oscillation of the stressstrain curve in the initial compaction stage,and simulate the shear and interlocking of the matrix in the stress dissipation stage.When establishing the discrete element model of foam concrete,the influence of pore shape should be considered.The compressive strength of the DEM model decreases linearly with the increase of the nonspherical rate of the pores in the model while the correlation coefficient is 0.94.

关 键 词：泡沫混凝土 离散元法 孔隙结构 非球形颗粒 单轴压缩 声发射 

分 类 号：TU528.2[建筑科学—建筑技术科学] TB332[一般工业技术—材料科学与工程]