预湿轻骨料对混合骨料混凝土工作性的影响  

Influence of Pre-wetted Light-weight Aggregates on Workability of Combined Aggregate Concrete

作　　者：陈瑜[1] 韩汤溢 

机构地区：[1]长沙理工大学交通运输工程学院,长沙410114

出　　处：《硅酸盐通报》2015年第11期3377-3382,3389,共7页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金青年项目(51302020)

摘　　要：本文研究预湿轻骨料对混合骨料混凝土工作性的影响,利用轻骨料吸水返水特性,发挥其对高效减水剂的"载体"和"缓释"作用以控制混凝土流动性。结果表明,干燥轻骨料所拌合的混凝土初始坍落度最大,轻骨料预湿1 h的其次,预湿24 h的最小;预湿轻骨料混凝土坍落度经时损失小;且高效减水剂溶入浸泡轻骨料的水中并预湿吸附,所制备的混合骨料混凝土数小时内坍落度不降反增。轻骨料吸水率越大、体积取代率越高及预湿时间越长,混凝土坍落度控制效果越好。The pre-wetted light-weight aggregates on workability of combined aggregate concrete was studied in the paper. The functions of both carrier and sustained releasing for superplasticizer above from the water absorbing and returning of light-weight aggregates were also analyzed on the purpose of controlling concrete flowability. Results show that fresh concrete using absolutely dry light-weight aggregates has the maximum initial slump, while that with 24 h pre-wetted light-weight aggregates is the minimum, and that with 1 h pre-wetted light-weight aggregates is in the middle of them. There are quite low slump losses with time in concretes added with pre-wetted light-weight aggregates, and if the superplasticizer is dissolved into water and absorbed into light-weigh aggregate particles in advance to produce concrete, it can be found that the slumps do not fall but rise within several hours. With the increasing of water absorption, volume percentage, as well as pre-wetting time of light-weight aggregates, there will be a better result of slump loss control of fresh combined aggregate concrete.

关 键 词：轻骨料 工作性 坍落度损失 高效减水剂 

分 类 号：TU528[建筑科学—建筑技术科学]