多元复合超细掺合料制备混凝土内部结构研究  

Study on the internal structure of concrete prepared by multi-component composite ultrafine admixture

作　　者：张雪丽[1] 侯付闯 ZHANG Xueli;HOU Fuchuang(Hangzhou Polytechnic,Hangzhou 311402,China;Shaanxi Zhongkai Hengrui Engineering Project Management Co.,Ltd.,Xi′an710065,China)

机构地区：[1]杭州科技职业技术学院,浙江杭州311402 [2]陕西中凯恒瑞工程项目管理有限公司,陕西西安710065

出　　处：《混凝土》2023年第10期116-119,共4页Concrete

摘　　要：研究多元复合超细掺合料制备混凝土内部结构的变化规律。结果表明:高活性超细矿物掺合料替代率为30%时,新拌混凝土性能优良,混凝土出机坍落度245 mm、扩展度700 mm,7 d抗压强度49.0 MPa、28 d抗压强度65.6 MPa,可明显改善混凝土工作性能且能保证较高的力学性能。超细掺合料的加入可改善胶凝材料颗粒分布,提高密实度。混凝土总孔隙率降低42.1%,200 mm以上孔隙率降低39.6%,混凝土气泡间距系数降低21.9%,同时可减少混凝土内部气泡的生成。The change law of the internal structure of concrete prepared by multi-component composite ultrafine admixture is studied.The results show that when the substitution rate of high-activity ultrafine mineral admixture is 30%.The fresh concrete has excellent performance.The concrete slump is 245 mm.The expansion degree is 700 mm.The 7 d compressive strength is 49.0 MPa.The 28 d compressive strength is 65.6 MPa.It can obviously improve the working performance of concrete and can ensure high mechanical properties.The addition of ultrafine admixtures can improve the particle distribution of the cementitious material and increase the density.The total porosity of concrete is reduced by 42.1%.The porosity above 200 mm is reduced by 39.6%.The concrete bubble spacing coefficient is reduced by 21.9%,and the generation of bubbles in the concrete can be reduced at the same time.

关 键 词：超细掺合料 孔径分布 孔连通性 气泡间距 微观形貌 

分 类 号：TU528.041[建筑科学—建筑技术科学]