Preparation and Performance of a Fluorine-Free and Alkali-Free Liquid Accelerator for Shotcrete

作     者：Jianbing Zhang Rongjin Liu Siyuan Fu Tianyu Gao Zhongfei Zhang 

作者机构：College of Material Science and EngineeringGuilin University of TechnologyGuilin541004China Guangxi Engineering and Technology Center for Utilization of Industrial Waste Residue in Building MaterialsGuilin541004China Guangxi Beibu Gulf Engineering Research Center for Green Marine MaterialsGuilin541004China 

出 版 物：《Journal of Renewable Materials》 (可再生材料杂志（英文）)

年 卷 期：2021年第9卷第11期

页      面：2001-2013页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 

基　　金：grateful funding provided by National Key Research and Development Program of China(Project 2019YFC1906202) Guangxi Key Research and Development Plan(Guike AB19259008) Major Science and Technology Special Project of Guangxi Province(Guike AA18242007-3) 

主　　题：Shotcrete alkali-free liquid accelerator setting time compressive strength mechanism 

摘      要：Based on aluminum sulfate,a fluorine-free and alkali-free liquid accelerator(FF-AF-A)was prepared in this *** setting time and compressive strength of three cement types with different FF-AF-A dosages were fully *** compatibility of the FF-AF-A with the superplasticizers were also investigated,and the early hydration behavior and morphology of the hydration products of reference cement paste with the FF-AF-A were explored by hydration heat,X-ray diffractometry(XRD),and scanning electron microscopy(SEM).Test results indicated that adding the FF-AF-A at 8 wt%of the cement weight resulted in 2 min 35 s initial setting time and 6 min 30 s final setting *** 1-day compressive strength of the cement mortar with 8 wt%of FF-AF-A reached 13.5 MPa,which represents an increase of 35%as compared to the strength of cement mortar without the FF-AF-A,and the 28-day compressive strength ratio was 119%.In addition,the FF-AF-A also showed good compatibility with different superplasticizer *** results show that,when the FF-AF-A was added to the cement paste,it promoted the formation of ettringite crystals due to the aluminum ions(Al^(3+))and sulfate ions(SO_(4)^(2-))reacted with gypsum in the cement,as well as promoted the hydration of tricalcium aluminate(C_(3)A)and tricalcium silicate(C3S)leading to the overall structure becomes more *** a consequence,the hydration heat rate of the cement sharply increased,the cement paste setting time is shortened,and the compressive strength of cement mortar is improved.