摘要
RVE(representative volume element)/REV(representative elementary volume)的存在性及其确定是尺度效应研究领域的一个基本科学问题.从复合材料微细观力学、岩土力学与工程领域分别分析了代表性体积单元(RVE)和表征单元体(REV)的异同,以后者为主要研究对象给出岩土介质REV研究的三层次分类.进一步以第三层次分类中的孔隙率、孔隙大小及分布分形维数为约束,引入分形几何理论描述岩土介质复杂孔隙结构,通过理论公式推演及与已有文献研究结果对比,提出了一种孔隙大小分布满足分形幂律特征条件下岩土介质孔隙率表征单元体(P-REV)尺度确定的近似判据,即岩土介质选择其内部最大孔隙孔径5倍的立方体单元即可作为微细观尺度孔隙结构(孔隙率)研究的REV.后续通过低阶概率函数等统计分析方法进行了验证,结果表明,以该近似判据确定的砂岩、泡沫混凝土等岩土试样P-REV与其他方法确定的结果基本吻合,可以给出具有代表性意义的统计结果,并在表征精度与计算效率之间提供合理的平衡点.
The representative volume element(RVE)and/or the representative elementary volume(REV)and their existence and determination are a basic scientific issue in the research field of size effect.The similarities and differences between the RVE and REV are analyzed from the fields of composite micromechanics and geotechnical engineering.A three-level classification of the REV research on geomaterials is then proposed based on these fields,especially REV research in geotechnical engineering.The pore size distribution and the corresponding fractal dimension are introduced and selected as the constrained parameters for describing the complex pore structure of geomaterials.Accordingly,an approximate criterion is first presented via theoretical deduction and comparison with previous research results,through which the size of a P-REV of mesoscale porous geomaterials can be determined using their pore size distributions(i.e.,the edge length of the cubic P-REV is approximately equal to five times of the maximum pore diameter).Finally,some statistical methods,such as low-order probability functions,are utilized to validate the performance of the proposed criterion.The verification results using two types of geomaterials,namely,sandstone and foamed concrete,reveal that both are in a reasonable agreement,indicating that the P-REV determined according to this approximate criterion can provide representative statistical results and find a balance between characterization accuracy and calculation efficiency.
作者
褚召祥
周国庆
饶中浩
赵光思
商翔宇
李瑞林
CHU ZhaoXiang;ZHOU GuoQing;RAO ZhongHao;ZHAO GuangSi;SHANG XiangYu;LI RuiLin(School of Electrical and Power Engineering,China University of Mining and Technology,Xuzhou 221116,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,Xuzhou 221116,China)
出处
《中国科学：技术科学》
EI
CSCD
北大核心
2021年第9期1107-1126,共20页
Scientia Sinica(Technologica)
基金
国家自然科学基金(批准号:41672343,41772338,41902273,42107156)
111创新引智计划(编号:B14021)
中国博士后科学基金(编号:2020M681777)
江苏省博士后科学基金(编号:2020Z434)资助项目。
关键词
岩土工程
表征单元体
孔隙
孔径尺寸分布
分形
geotechnical engineering
representative elementary volume
pore
pore size distribution
fractal
