大流动性高强轻集料混凝土工作性能研究

采用混凝土拌合物质量分层度、轻集料质量分层度、泌水度以及坍落度和扩展度5项指标来综合评价轻集料混凝土拌合物的流动性和稳定性，试验研究了胶凝材料用量、砂率、矿物掺合料和引气剂对大流动性的高强轻集料混凝土工作性能的影响。结果表明，胶凝材料用量、砂率和引气剂掺量存在一个最优值，此时轻集料混凝土的流动性最大且稳定性好；粉煤灰和矿渣掺人能较大程度地提高混凝土拌合物的工作性能，复合双掺时效果更好。

Workability of High Strength Lightweight Aggregate Concrete with High Fluidity

In order to evaluate the fluidity and stability of fresh high strength lightweight aggregate concrete with high fluidity, five important parameters have been introduced i.e. the mixture mass difference at different layers, the lightweight aggregate mass difference at different layers, the bleeding difference at different layers, the slump and the extendability. And the influence of four key factors, which are the content of cementing material, sand ratio, mineral admixture and air-entrainer, on the fluidity of high strength lightweight aggregate concrete have been tested. The results indicate that the cementing material, sand percentage and the content of air-entrainer have an optimum value to satisfy high liquidity and stability. Mineral admixtures can greatly improve the workability of concrete. And the effect of combining fly-ash and blast-furnaced slag is better than that of using of single one.