超缓凝混凝土配合比设计及工程应用  

Mix Design and Engineering Application of Ultra-retardation Concrete

作　　者：葛运成 张春祥 张硕 彭佳 庞永龙 邢延达 

机构地区：[1]北京市高强混凝土有限责任公司,北京100071

出　　处：《混凝土世界》2024年第2期44-52,共9页China Concrete

摘　　要：超缓凝混凝土是一种能在较长时间内通过调整超缓凝高效减水剂掺量,改变凝结时间但不破坏混凝土性能,且其后期强度与普通混凝土无较大差异的新型混凝土。目前,超缓凝混凝土主要应用于高层建筑和地铁修建过程中的深基坑支护结构以及对混凝土凝结时间有特殊要求的超大体积混凝土,如超长大直径水下桩基工程,其在地铁车站等咬合桩施工中有广泛的应用优势。本文从工程实际要求出发,利用北京市地区常用原材料和苏博特超缓凝减水剂,配制出初凝时间大于36 h,24 h内具备一定流动性,7 d强度低于17.5 MPa,且28 d强度满足设计指标的C35超缓凝混凝土,并成功应用于实际工程施工中。Ultra-retardation concrete is a new type of concrete that can change the setting time over a long period of time by adjusting the dosage of water-reduction retarder,without damaging the concrete performance,and its later strength is not significantly different from ordinary concrete.At present,ultra-retardation concrete is mainly used in deep foundation pit support structures in high-rise buildings and subway construction processes,as well as ultra-large volume concrete with special requirements for concrete setting time,such as ultra-long diameter underwater pile foundation engineering.It has a wide range of application advantages in the construction of interlocking piles in subway stations and other areas.Starting from the practical requirements of engineering,this paper uses commonly used raw materials in Beijing and Subote super retarder water reducing agent to prepare C35 super retarder concrete with an initial setting time greater than 36 hours,certain fluidity within 24 hours,a 7 days strength lower than 17.5 MPa,and a 28 days strength that meets the design indicators.It has been successfully applied in practical engineering construction.

关 键 词：超缓凝混凝土 超缓凝减水剂 水胶比 掺合料 砂率 工程应用 

分 类 号：TU528[建筑科学—建筑技术科学]