硅灰和水泥对免蒸压加气混凝土的性能影响与微观分析  

Effect of silica fume and cement on properties of non‐autoclaved aerated concrete and microanalysis

作　　者：罗杰波 彭晓彤[1] 刘兆磊 王忠清 张秀芝[2] LUO Jiebo;PENG Xiaotong;LIU Zhaolei;WANG Zhongqing;ZHANG Xiuzhi(School of Civil Engineering and Architecture,University of Jinan,Jinan 250022,China;School of Materials Science and Engineering,University of Jinan,Jinan 250022,China;China Railway Tenth Bureau Group Co.,Ltd.,Yantai 264001,China)

机构地区：[1]济南大学土木建筑学院,山东济南250022 [2]济南大学材料科学与工程学院,山东济南250022 [3]中铁十局集团城建工程有限公司,山东烟台264001

出　　处：《中国粉体技术》2025年第2期152-160,共9页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:52178211。

摘　　要：【目的】研发一种采用免蒸压工艺的新型加气混凝土;在不显著增加导热系数的基础上,通过优化硅灰掺量和水泥标号,确定提高强度的最佳试验配比。【方法】设计不同硅灰替代率的单因素试验,在此基础上复掺水泥,对比分析各试件的干密度和抗压强度,同时通过扫描电子显微镜分析最优免蒸压加气混凝土的微观形貌与孔隙特征。【结果】随着硅灰掺量(质量分数,下同)的增加和水泥强度的提高,免蒸压加气混凝土的干密度和抗压强度均增大,而导热系数没有明显变化;免蒸压加气混凝土硅灰的最佳掺量为4%,用P.O52.5硅酸盐水泥制备的免蒸压加气混凝土的性能更优,相应试件的干密度为798kg/m^(3),抗压强度为3.9MPa,导热系数为0.09553W/(m·K),符合《蒸压加气混凝土制品应用技术标准》中A2.5B06级加气混凝土的性能要求。【结论】在保持自保温墙板理想导热系数的前提下,优化硅灰掺量与水泥强度是提高材料强度的有效途径。Objective An innovative non-autoclaved aerated concrete(NAAC)is developed to achieve an optimal balance between thermal insulation and mechanical properties,addressing the demand for energy efficiency and environmental sustainability in construction.Traditionally,the production of aerated concrete relies on autoclaving to enhance material strength,which is highly energyconsuming and has stringent requirements on equipment.To overcome these limitations,the study focuses on the nonautoclaved process,systematically optimizingraw materials ratios to enhance material performance.By refining silica fume dosing and cement grade,the optimal test ratios for strength enhancement are determined without significantly increasing thermal conductivity.Methods This study used a single-factor test method to optimize the composition in aerated concrete.By designing tests with varying silica fume substitution rates,the dry density and compressive strength of each specimen were analyzed.Based on these results,the cement grade was varied to determine the optimal silica fume admixture and cement grade.Firstly,a small amount of silica fume was used to address the insufficient strength of traditional autoclaved aerated concrete while ensuring minimal impact on thermal conductivity.The effects of silica fume content on material performance were assessed to determine the optimal substitution rate.Subsequently,the effects of different cement grades on NAAC performance were explored through additional tests.Finally,the microstructure of the optimal NAAC was analyzed using a scanning electron microscope(SEM).Results and Discussion Optimizing silica fume content and cement grade proved effective in improving the strength of NAAC,while maintaining the ideal thermal conductivity for self-insulated wall panels.Increasing silica fume content improved the dry density and compressive strength of the material.At a silica fume substitution rate of 2%,the dry density was the smallest,while at a substitution rate of 10%,the compressive strength was the

关 键 词：免蒸压加气混凝土 干密度 抗压强度 硅灰 微观结构 

分 类 号：TU528[建筑科学—建筑技术科学] TB4[一般工业技术]