地下工程自密实自防水混凝土应用研究

针对地下工程泵送混凝土施工时易产生裂缝、渗水现象,采用粉煤灰、膨胀剂、缓凝高效减水剂＂三掺＂技术,优化配合比设计,配制自密实混凝土,有效控制裂缝,以达到自防水目的。试验研究和工程实践表明：复合外掺剂有效地提高了混凝土流动性,增加了混凝土的密实度,提高了混凝土的抗渗性能,满足地下工程结构自防水的设计要求。

Application Research of Self-compact and Self-waterproofing Concrete in Underground Engineering

Against the problems of crack and water penetration during underground construction using pump concrete,with the admixture of fly ash,expansion agent and retarded high range water-reducing agent,the proportion design is optimized and self-compact concrete is prepared in order to control the crack and meet the requirement of self-waterproofing.Through the laboratory test and engineering practice,it is proven that compound mixed agent effectively improved the fluidity and compactness of concrete,and thus improved the impermeability of concrete,which satisfied the design requirement of self-waterproofing of underground structure.