江下水库自密实混凝土配合比设计及性能分析

Design and Performance Analysis of Self-compacting Concrete Mix in Jiangxia Reservoir

针对江西省江下水库工程,开展了自密实混凝土的配合比设计及性能分析,获取混凝土流动性、水胶比、浆骨比、砂率等因素对混凝土性能的影响。试验结果显示,当胶凝材料用量为640 kg/m^(3)时,通过调整水胶比,混凝土的流动性得到显著提升,且未出现离析或泌水现象。浆骨比对混凝土早期抗压强度有显著影响,而随龄期增长,抗压强度在浆骨比为36:64时达到最优。砂率的优化对混凝土流动性及工作性能至关重要,试验条件下,最佳砂率为40%。基于上述研究成果,提出了C20W6F50高自密实性能混凝土的推荐配合比,并通过试拌验证其满足设计指标要求,具有较高的抗压强度、抗渗抗冻性能,为江西江下水库自密实混凝土施工提供了理论支持和实践指导。

The mix design and performance analysis of self-compacting concrete were carried out for the Jiangxia Reservoir project in Jiangxi.The influence of factors such as concrete flowability,water cement ratio,slurry to bone ratio,and sand ratio on concrete performance were obtained.The experimental results showed that when the dosage of cementitious material was 640kg/m^(3),the flowability of concrete was significantly improved by adjusting the water cement ratio,and there was no segregation or bleeding phenomenon.The ratio of slurry to bone had a significant impact on the early compressive strength of concrete,and with the increase of age,the compressive strength reached its optimum at a ratio of slurry to bone of 36:64.The optimization of sand ratio was crucial for the fluidity and workability of concrete,and under the experimental conditions,the optimal sand ratio was 40%.Based on the above research results,the recommended mix proportion for C20W6F50 high self-compacting performance concrete was proposed,and the trial mixing verified that it met the design index requirements,had high compressive strength,impermeability,and frost resistance.It provides theoretical support and practical guidance for the construction of self-compacting concrete in Jiangxia Reservoir,Jiangxi.