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
周程涛 1陈波 1高志涵 1陈家林 1陈锴2
作者信息
- 1. 河海大学 水灾害防御全国重点实验室,南京 210098;河海大学 水利水电学院,南京 210098
- 2. 国家能源局大坝安全监察中心,杭州 311122;中国电建集团华东勘测设计研究院有限公司,杭州 311122
- 折叠
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/m3 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.
Abstract
In order to study the fitness of discrete element method(DEM)in the simulation of mechanical pro-perties 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/m3.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 stress-strain 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 non-spherical 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Key words
foam concrete/discrete element method/pore structure/non-spherical particles/uniaxial compres-sion test/acoustic emission引用本文复制引用
基金项目
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)
国家重点实验室基本科研业务费(5230248A2)
出版年
2024
NETL
NSTL
万方数据