低掺量高早强速凝剂在喷射混凝土中的实际应用  

Application of Low-dosage High Early Strength Accelerating Agent in Shotcrete

作　　者：尚百雨 万维福 

机构地区：[1]北京金隅混凝土有限公司,北京100165 [2]中国混凝土与水泥制品协会喷射混凝土材料与工程技术分会,北京100011

出　　处：《混凝土世界》2024年第5期27-31,共5页China Concrete

摘　　要：针对某工程初支喷射混凝土存在回弹率严重偏高、安全隐患大等问题,结合现场使用材料,在工区中心试验室开展了对比试验,优化速凝剂的配合比与制备工艺,调配出一种与工程现场使用材料相容性优异、掺量低、高早强的速凝剂(SJC-1)。结果表明:在SJC-1掺量较现场用速凝剂降低20%的情况下,喷射混凝土的回弹率可控制在10%以内,其3 h强度提高150%以上,6 h强度提高300%以上,初支喷射混凝土的支护功能得到有效发挥,安全风险大大降低;此外,在经济效益方面,通过对比发现,使用SJC-1可以有效降低工程造价,综合效益提升显著。This paper focuses on the problems of severe high rebound rate and significant safety hazards in the initial stage of project shotcrete,combining with the materials used on site,carries out a large number of comparative experiments in the central laboratory of the work area to optimize the mix proportion and preparation process of the rapid setting agent,formulates a rapid setting agent(SJC-1)with excellent compatibility,low-dosage,and high early strength with the materials used on site.The results show that when the SJC-1 dosage is reduced by 20%compared to the on-site use of rapid setting agent,the rebound rate of sprayed concrete can be controlled within 10%,its 3 hours strength can be increased by more than 150%,and its 6 hours strength can be increased by more than 300%.The initial support function of sprayed concrete is effectively exerted,and the safety risk is greatly reduced;in addition,in terms of economic benefits,it was found through comparison that using SJC-1 can effectively reduce project costs and significantly improve overall benefits.

关 键 词：喷射混凝土 回弹率 低掺量 高早强 速凝剂 

分 类 号：TU528.53[建筑科学—建筑技术科学]