C40风积砂混凝土孔结构-强度模型研究  

Pore Structure-strength Model of C40 Aeolian Sand Concrete

作　　者：张慧梅[1] 郑世航 景盼园 袁超 李玉根 ZHANG Huimei;ZHENG Shihang;JING Panyuan;YUAN Chao;LI Yugen(College of Science,Xi’an University of Science and Technology,Xi’an 710054,China;College of Architecture and Civil Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;1st Bureau,China Metallurgical Geology Administration,Langfang 065201,China;School of Architecture Engineering,Yulin University,Yulin 719000,China)

机构地区：[1]西安科技大学理学院,陕西西安710054 [2]西安科技大学建筑与土木工程学院,陕西西安710054 [3]中国冶金地质总局一局,河北廊坊065201 [4]榆林学院建筑工程学院,陕西榆林719000

出　　处：《河南科技大学学报（自然科学版）》2023年第6期77-83,M0007,共8页Journal of Henan University of Science And Technology:Natural Science

基　　金：国家自然科学基金项目(12172280,52268047,51868075);陕西省自然科学基金重点项目(2020JZ-53)。

摘　　要：对C40风积砂混凝土进行宏观力学试验,结合扫描电镜(SEM)和核磁共振(NMR)技术,探讨风积砂混凝土孔隙结构与力学性能之间的内在关系,揭示其影响机理。利用回归分析,建立双因素下孔结构-强度模型。结果表明:随风积砂替代率的增加,风积砂混凝土微观结构先紧密后松散,孔隙率与无害孔占比先减后增大,抗压强度先增大后减小,替代率20%时抗压强度最高。适量的风积砂改善混凝土骨料级配,细化孔隙,使受荷面初始损伤减小,宏观性能增强。建立的以无害孔占比和无害孔隙率为因变量的孔结构-强度模型能较好地预测混凝土强度。The macroscopic mechanical test of C40 aeolian sand concrete was carried out.Combined with scanning electron microscope(SEM)and nuclear magnetic resonance(NMR)technology,the internal relationship between pore structure and mechanical properties of aeolian sand concrete was discussed,and the influence mechanism was revealed.The regression analysis was used to establish the pore structure-strength model under two factors.The results show that with the increase of aeolian sand replacement rate,the microstructure of aeolian sand concrete is compact first and then loose,the porosity and harmless pore ratio decrease first and then increase,and the compressive strength increases first and then decreases.When the replacement rate is 20%,the strength is the highest.The appropriate amount of aeolian sand improves the aggregate gradation of concrete,refines the pores,reduces the initial damage of the loading surface,and enhances the macroscopic performance.The established pore structure-strength model with harmless pore ratio and harmless porosity as dependent variables can better predict the strength of concrete.

关 键 词：风积砂混凝土 力学性能 孔隙结构 影响机理 预测模型 

分 类 号：TU528[建筑科学—建筑技术科学]