高强高保坍钢管拱机制砂自密实混凝土配制技术  

Preparation technology of high-strength and high workability-retention self-compacting concrete with manufactured sand for steel pipe arch

作　　者：袁星[1,2] 周泽林 陈延松[2] 汤宇祺 黄盛 任强 YUAN Xing;ZHOU Zelin;CHEN Yansong;TANG Yuqi;HUANG Sheng;REN Qiang(Southwest Jiaotong University,Chengdu 610031,China;China 19th Metallurgical Group Corporation Limited,Chengdu 610017,China;Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education,Tongji University,Shanghai 201804,China;Guizhou Bridge Construction Group Co.Ltd.,Guiyang 550001,China)

机构地区：[1]西南交通大学,四川成都610031 [2]中国十九冶集团有限公司,四川成都610017 [3]同济大学先进土木工程材料教育部重点实验室,上海201804 [4]贵州桥梁建设集团有限责任公司,贵州贵阳550001

出　　处：《新型建筑材料》2024年第4期82-87,共6页New Building Materials

基　　金：宁波市重大科技攻关暨揭榜挂帅项目(2022Z030);中央高校基本科研业务费专项资金资助项目。

摘　　要：根据重庆某钢管拱桥结构特征与“泵送顶升压注法”施工工艺特点,提出了高强高保坍钢管拱机制砂自密实混凝土性能需求。针对高强与超高工作性的矛盾问题,通过配合比参数优化、骨料优化、矿物掺合料复掺优化、外加剂复配优化和配合比综合优化等技术,配制出初始坍落度≥260 mm、扩展度≥600 mm、倒坍落度筒流出时间≤8 s、4 h工作性基本无损失、强度等级达C60以上的钢管拱机制砂自密实混凝土,形成了高强高保坍钢管拱机制砂自密实混凝土的配制技术,为工程实际施工提供了良好的技术支撑。According to the structural characteristics of a Steel Pipe Arch Bridge in Chongqing and the construction technology requirement of pump-up construction method,the performance requirements of high-strength and high workability-retention of self-compacting concrete with manufactured sand(SCC-MS)are proposed.Aiming at the contradictory between the high strength and super high workability of concrete,the optimizing technologies of mix proportions,aggregate,blended mineral admixtures,compound of chemical admixtures and combined factors were investigated.Finally,the concrete mixtures with the initial slump not less than 260 mm,slump flow not less than 600 mm,inverted slump outflow time not exceeding 8 s and no loss of workability in 4 h,were prepared and their strength grade is higher than C60.Therefore,the preparation technology of high strength SCC-MS with a high workability retention was proposed for the construction of steel arch bridge,providing good technical support for actual construction.

关 键 词：钢管拱 机制砂 自密实混凝土 高强 高保坍 配合比 

分 类 号：TU528.041[建筑科学—建筑技术科学]