自密实轻骨料混凝土工作性能的研究

Workability of self-compacting lightweight aggregate concrete

采用改进的L-800自密实混凝土拌合物流变性能测定仪,通过测定混凝土拌合物流过40cm,同时结合扩展度值、坍落度值及1h坍落度、扩展度损失情况,介绍了粉煤灰掺量、砂率大时的时间t40小、外加剂品种和硅灰掺量对自密实轻骨料混凝土拌合物工作性的影响。结果表明,30%左右Ⅰ级粉煤灰、50%左右体积砂率、2%～6%硅灰掺量和掺有粘塑组分的复合高效减水剂是保证自密实轻骨料混凝土拌合物具有较好工作性能的关键。

The influences of fly ash, sand ratio, kinds of chemical admixtures and dosages of silicon fume on mixtures of self-compacting lightweight aggregate concrete were introduced by the ways of adopting L-800 rheological testing apparatus of concrete mixtures mended to test the value of t(40),which was the time when concrete mixtures flowing the length of 40 cm, combining with the values of expansion, slump and losses of both after an hour at the same time. The result indicated that the key techniques ensuring SCLC to have good workability were about 30% first-grade fly ash, about 50% volume sand ratio,2%～6% dosages of silicon fume and compounded superplasticicizers with viscous ingredient.