A Study on Curing Properties of Concrete of Containing Large Quantity of Fly Ash

本研究对含大量粉煤灰的混凝土在40℃空气养护条件下的强度与混凝土的强度进行了试验，分两个水平（普通强度混凝土区和高强混凝土区单位体积混凝土的水泥含量）。研究结论如下。当粉煤灰掺量过大时，澄清了单位体积水泥掺量大时，混凝土抗压强度没有提高。当其与混凝土混合达到单位体积混凝土粉煤灰掺量约100 kg/m^3，且单位体积混凝土水泥掺量较大，达到标准养护时，抗压强度表达式最优。即使再混合，效果也不大。标准养护时，单位体积水泥掺量600kg/ mm^ 3及以上的混凝土抗压强度约为100N/mm^2。但在40℃空气养护条件下，混凝土的抗压强度较差，约为80N/mm^2。当与混凝土混合至单位体积混凝土粉煤灰掺量约200 kg/m^3时，40℃空气养护混凝土的抗压强度（本试验为110N/m^2）与标准养护基本相同。(2)预拌混凝土厂试验在冲绳县预拌混凝土生产厂家，对冲绳县的粉煤灰进行了浆化处理。采用掺量较大的粉煤灰浆体混凝土制备模拟柱试件。并对其强度特性进行了澄清。研究结论如下。在预拌混凝土厂的实际搅拌试验中，掺加大量粉煤灰浆的混凝土抗压强度明显高于不掺粉煤灰浆的混凝土。

(1) The Laboratory ExperimentIn this study, it was experimented concerning the strength of concrete containing large quantity of fly ash under 40 degrees centigrade air curing was severe with concrete, in two levels (cement content per unit volume of concrete of the normal strength concrete area and the high-strength concrete area). The conclusions are as follows. When the mixed quantity of fly ash was too large, it was clarified not to show the compressive strength improvement when the cement content per unit volume of concrete was large. When it mixed with concrete up to the fly ash content per unit volume of concrete about 100 kg/m^3 when the cement content per unit volume of concrete was large, and it made it to standard curing, the expression of compressive strength was optimal. And the effect is a little even if it mixes it any more. The compressive strength of concrete at the cement content per unit volume of concrete 600kg/m^3 or more showed about 100N/mm^2 in standard curing. But compressive strength under 40 degrees centigrade air curing was severe with concrete was shown about 80N/mm^2. When it mixed with concrete up to the fly ash content per unit volume of concrete about 200 kg/m^3, the concrete of 40 degrees centigrade air curing showed almost same compressive strength (110N/m^2 in this experiment)as standard curing.(2) Experiment at Ready-mixed Concrete PlantIn the ready mixed concrete producer in Okinawa Prefecture, The fly ash exhausted in Okinawa Prefecture was slurried. The simulated column specimen was made by using concrete containing large quantity fly ash slurry. And the strength properties of it was clarified. The conclusions are as follows. In actual mixer experiment at ready-mixed concrete plant, the concrete containing large quantity the fly ash slurry showed compressive strength that was higher than the concrete no containing fly ash slurry.