初始损伤下改性脱硫石膏基混凝土渗透性及孔隙结构研究  

Study on Permeability and Pore Structure of Modified Desulfurized Gypsum-based Concrete Under Initial Damage

作　　者：毛运之 薛维培 徐林峰 王中建 MAO Yun-zhi;XUE Wei-pei;XU Lin-feng;WANG Zhong-jian(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China;State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]安徽理工大学土木建筑学院,淮南232001 [2]安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室,淮南232001

出　　处：《武汉理工大学学报》2024年第8期26-31,共6页Journal of Wuhan University of Technology

基　　金：国家自然科学基金青年项目(52308228);安徽省自然科学基金面上项目(2208085ME146);教育部“春晖计划”合作科研项目(HZKY20220204)。

摘　　要：以不同程度预压荷载处理后的脱硫石膏基混凝土作为研究对象,先经历干湿冻融循环后开展三轴渗透试验,研究荷载损伤和干湿冻融循环对试件渗透性能的影响;探究试件内部孔隙结构的发展规律。结果表明:与弹性预压荷载试件相比,塑性预压荷载试件受到干湿冻融循环的影响更大,初始渗透率增长了6.15×10^(-17)m^(2);受围压增大的影响,渗透率呈逐渐减小趋势。由T_(2)谱曲线、分形维数的演化规律发现,干湿冻融循环促使混凝土内部孔隙逐渐向大孔发展;随着循环次数的增加,分形维数逐渐减小,孔隙复杂程度降低。孔隙率与渗透率之间呈现非线性关系。Taking the desulfurization gypsum-based concrete treated with different degrees of pre-compression load as the research object,triaxial penetration tests were carried out after undergoing dry and wet freeze-thaw cycles first,to study the effects of load damage and dry and wet freeze-thaw cycles on the penetration performance of the specimens;and to investigate the development law of the internal pore structure of the specimens.The results show that compared with the elastic preloaded specimen,the plastic preloaded specimen is more affected by the wet and dry freeze-thaw cycles,and the initial permeability increases by 6.15×10^(-17)m^(2);the permeability tends to decrease gradually under the influence of the increase of the perimeter pressure.From the T_(2) spectral curve,the evolution law of fractal dimension,it was found that the dry and wet freeze-thaw cycles prompted the internal pores of the concrete to develop gradually to large pores;with the increase of the number of cycles,the fractal dimension gradually decreased,and the complexity of the pores decreased.The porosity and permeability showed a nonlinear relationship.

关 键 词：荷载损伤 干湿冻融 脱硫石膏 分形维数 孔隙结构 

分 类 号：TU528[建筑科学—建筑技术科学]