含粗骨料UHPC的强度尺寸效应与性能研究  

Study on strength size effect and performance of UHPC with coarse aggregates

作　　者：王军 刘晓峰 陈镇衫 罗西 余辉 廖树基 WANG Jun;LIU Xiaofeng;CHEN Zhenshan;LUO Xi;YU Hui;LIAO Shuji(Mingyang Smart Energy Group Co.,Ltd.,Zhongshan 528437,China)

机构地区：[1]明阳智慧能源集团股份公司,广东中山528437

出　　处：《混凝土与水泥制品》2024年第5期51-56,共6页China Concrete and Cement Products

基　　金：中山市重大科技专项项目(20220506)。

摘　　要：研究了胶凝材料组成比例、钢纤维类型(平直型、端钩型)对含粗骨料超高性能混凝土(UHPC)强度尺寸效应、工作性和收缩性能的影响,分析了减缩剂掺量(0~2.0%)对含粗骨料UHPC收缩性能、力学性能、抗氯离子渗透性能和孔结构的影响。结果表明:适当增加粉煤灰掺量有利于改善含粗骨料UHPC的工作性,降低收缩;掺入钢纤维降低了含粗骨料UHPC的工作性,但抑制了收缩,且端钩型钢纤维抑制效果更显著;掺入1%钢纤维能够有效降低含粗骨料UHPC的强度尺寸效应,且平直型钢纤维的降低效果更好;掺入减缩剂明显降低了含粗骨料UHPC的收缩,但会使抗压强度降低,总孔隙率增大,抗氯离子渗透性能变差。The effects of the composition ratio of cementitious materials and the type of steel fibers(straight and end-hooked)on the strength size effect,workablity and shrinkage properties of ultra-high performance concrete(UHPC)with coarse aggregates were investigated,and the effects of the content of shrinkage reducing agent(0~2.0%)on the shrinkage properties,mechanical properties,chloride ion penetration resistance and pore structure of UHPC with coarse aggregates were analyzed.The results show that increasing the content of fly ash appropriately is conducive to improving the workability and reducing the shrinkage of UHPC with coarse aggregates.The addition of steel fibers reduces the workability of UHPC with coarse aggregates,but inhibits the shrinkage,and the suppression effect is more significant with end-hooked steel fibers.Adding 1%content of steel fibers effectively reduces the strength size effect of UHPC with coarse aggregates,and the reduction effect of the straight steel fibers is better.The addition of shrinkage reducing agent obviously reduces the shrinkage of UHPC with coarse aggregates,but reduces the compressive strength,increases the total porosity,and deteriorates the chloride ion penetration resistance.

关 键 词：含粗骨料超高性能混凝土 尺寸效应 钢纤维 减缩剂 收缩性能 力学性能 抗氯离子渗透性能 

分 类 号：TU528.572[建筑科学—建筑技术科学]