混凝土单轴压缩下表面裂纹分布多重分形特征  

Multifractal Characteristics of Surface Crack Distribution in Concrete under Uniaxial Compression

作　　者：吴剑锋[1,2] 李赫赫 马德源 王彩华[1,2] WU Jianfeng;LI Hehe;MA Deyuan;WANG Caihua(School of Civil and Architectural Engineering,Northeast Petroleum University,Daqing 163318,Heilongjiang,China;Northeast Petroleum University Qinhuangdao,Qinhuangdao 066044,Hebei,China;Qinhuangdao Xinglong Construction Engineering Co.,Ltd.,Qinhuangdao 066300,Hebei,China)

机构地区：[1]东北石油大学土木建筑工程学院,黑龙江大庆163318 [2]东北石油大学秦皇岛校区,河北秦皇岛066044 [3]秦皇岛兴龙建设工程有限公司,河北秦皇岛066300

出　　处：《力学季刊》2023年第4期904-913,共10页Chinese Quarterly of Mechanics

基　　金：东北石油大学青年科学基金(2018QNQ-02)。

摘　　要：为研究混凝土在单轴压缩条件下表面裂纹分布的多重分形特征,利用多重分形理论对混凝土单轴压缩表面裂纹分布多重分形广义维数Dq进行了定量计算.分析了粗骨料平均粒径、试样尺寸、峰值应力、峰值应变、单位体积吸收能、应力水平等因素对广义维数阈值宽度ΔDq的影响.建立了基于广义维数阈值宽度ΔDq的混凝土单轴压缩弹性分形损伤本构方程.结果表明,混凝土在单轴压缩条件下表面裂纹分布具有多重分形特征;广义维数阈值宽度ΔDq随着峰值应力、峰值应变、单位体积吸收能以及应力水平的增加而增大,随粗骨料平均粒径和试样尺寸的增加呈降低趋势;单轴压缩弹性分形损伤本构方程理论曲线与试验曲线吻合良好.研究结果可为探究混凝土裂纹分布规律提供参考.To study the multifractal characteristics of surface crack distribution in concrete under uniaxial compression,the multifractal generalized dimension Dq of the surface crack distribution in concrete under uniaxial compression was quantitatively calculated using the multifractal theory.The effects of coarse aggregate particle size,sample size,peak stress,peak strain,absorbed energy per unit volume,and stress level on the generalized dimension threshold widthΔDq were analyzed.Based on the generalized dimension threshold widthΔDq,the elastic fractal damage constitutive equation for concrete under uniaxial compression was established.The results show that the distribution of surface cracks in concrete under uniaxial compression has multifractal characteristics.The generalized dimension threshold widthΔDq increases with the increase of peak stress,peak strain,absorbed energy per unit volume,and stress level,but decreases with the increase of coarse aggregate particle size and sample size.The theoretical curve of elastic fractal damage constitutive equation under uniaxial compression agrees well with the experimental curve.These results in this paper can provide insights into the distribution pattern of concrete cracks.

关 键 词：混凝土 单轴压缩 表面裂纹 多重分形 广义维数 本构方程 

分 类 号：TU528[建筑科学—建筑技术科学]