摘要
不同于天然骨料,再生骨料表面附着有硬化水泥砂浆,黏附的水泥砂浆使再生骨料具有更高的孔隙率、吸水率以及更低的强度.从而对再生骨料混凝土的性能产生不利的影响.为了改善再生混凝土的性能,国内外学者从混凝土搅拌工艺入手,研究不同的搅拌工艺对再生混凝土性能的影响.本文主要介绍了目前使用较多的两种再生混凝土搅拌工艺,即二次搅拌工艺和三次搅拌工艺.与传统搅拌工艺相比,采用二次搅拌工艺可以显著的改善再生混凝土的界面过渡区,提高再生混凝土的强度,同时还可增强再生混凝土的抗渗透性以及抗冻性等多方面的性能;在二次搅拌的基础上,三次搅拌工艺增加颗粒细度更小的矿物掺合料搅拌阶段,能进一步填充骨料的孔隙和缝隙及界面过渡区,使得制备的再生混凝土在强度和耐久性方更佳。
Unlike natural aggregate,the surface of recycled concrete aggregate(RCA)contains old cement mortar resulted in higher porosity and water absorption and low mechanical strength.Thus,affecting the performance of recycled aggregate concrete(RAC).In order to improve the performance of RAC,different mixing processes on the performance of RAC have been widely studied and researched.It provides an overview understanding of two types of mixing methods used,namely secondary mixing method and triple mixing method.Compared with the traditional mixing method,the secondary mixing method can improve the interface transition zone(ITZ),strength and durability including the permeability and frost resistance.On the basis of the secondary mixing method,the triple mixing method which include the very fine particles during the mixing stage to further improve the pores filling effect and enhanced the ITZ between the RCA and cement paste,thereby enhance the mechanical strength and durability of RAC.
作者
成全
LING Tung-Chai
李波
CHENG Quan;LING Tung-Chai;LI Bo(College of Civil Engineering,Hunan University,Changsha 410082,China;Department of Civil Engineering,University of Nottingham Ningbo China,Ningbo 315100,China)
出处
《混凝土》
CAS
北大核心
2019年第7期140-144,共5页
Concrete
基金
国家自然科学基金—2017年外国青年学者研究基金项目（51750110506）
湖南省重点研发计划项目“一带一路”技术合作与人文科技交流合作专项（2017WK2090）
关键词
再生骨料
再生混凝土
二次搅拌工艺
三次搅拌工艺
recycled concrete aggregate
recycled aggregate concrete
secondary mixing method
triple mixing method
