Study on Development of Fine Aggregate for Concrete and its Effective Utilization

研究了分解花岗岩、中国砂、城市生活垃圾气化渣、废玻璃碎料作为混凝土的细骨料，并对新拌混凝土和硬化混凝土的性能进行了研究。随后，采用3种分解花岗岩，其中1种来自3种坝址产地，进行了配合比和混凝土配制，混凝土含水率为150 kg/m3，坍落度为8 cm。检查。分析了该配合比设计中存在的问题，并与普通砂混凝土进行了性能比较。试验结果表明，与普通混凝土相比，分解花岗岩混凝土坍落度随时间损失较大，渗水量几乎为零，凝结时间短，使用缓凝型引气型高范围减水剂可以改善混凝土的物理性能，使其与普通混凝土的物理性能基本一致。在第二项研究中，研究了中国砂和工业废料细粉作为混凝土细骨料的有效利用。首先，将破碎砂、河砂和两种中国砂混合配制成三种细骨料，研究了细骨料类型对混凝土性能的影响。其次，将0.15mm以下的细颗粒粉末与中国砂混合，因为中国砂在0.15mm以下的细颗粒量很少。所选细粒粉有碎石细粉、镍铁渣细粉、玻璃细粉、干污泥粉和石灰石粉两种。研究了细颗粒类型对混凝土性能的影响。试验结果表明，含中国砂的混凝土粘度差、渗血大，除镍铁渣细粉外，这些不良性能都得到了改善。第三，研究了两种气化生活垃圾渣，探讨了其作为混凝土细、粗骨料的可能性。由于所选用的生活垃圾矿渣满足混凝土细骨料的质量标准，因此可能性高。细骨料矿渣置换率为50%、粗骨料矿渣置换率为80%的混凝土产品在强度和抗冻冻性能方面没有问题。因此，判断该产品可以投入使用。少

In this study, the decomposed granite, Chinese sand, Gasification slag from municipal solid waste, and waste glass cullet as fine aggregate for concrete were dealt with and the properties of fresh and hardened concrete were investigated. Subsequently, mix proportion and manufacture of concrete with water content of 150 kg/m3 and slump of 8 cm using three kinds of decomposed granite including one from three kinds of Togou Dam site origin were conducted. The examined. The problems with this mix design, and the properties of the fresh and hardened concrete with the decomposed granite also were examined and compared with that of ordinary concrete with normal sand. The test results showed that the disadvantage of concrete with the decomposed granite where (1)slump loss with time is larger, (2)bleeding becomes almost equal to zero, and (3)setting time becomes short compared with that of the ordinary concrete, could improve to have almost the same physical properties as that of ordinary concr … More ete with normal sand by using a retarder type of air-entraining high-range water deducing agent.In second study, effective utilization of Chinese sand and fine powders of industrial waste as fine aggregate for concrete was examined. At first, three types of fine aggregate were prepared mixing crushed sand, river sand and two types of Chinese sand and the effect of the type of fine aggregate on the properties of concrete. Secondly, fine particles powder less than 0.15mm were mixed with Chinese sand, because Chinese sand has a little quantity of fine particle under 0.15mm. The selected fine particle powder were crushed stone fine powder, ferro-nickel slag fine powder, glass fine powder, pulverized dry sludge powder and two types of limestone powder. The effects of type of fine particle on the properties of concrete were examined. Test results showed that the concrete with Chinese sands was poor viscosity and much bleeding, and these undesirable properties were improved with the fine particle except for ferro-nickel slag fine powder,Third study examined two kinds of gasification MSW (Melting Slag from Municipal Solid Waste) slag and examined the possibility of its utilization as fine and coarse aggregate for concrete. It is clear that the possibility is high because the selected MSW slag satisfies the quality standard fine aggregate for concrete. The concrete product of 50% slag replacement ratio to fine aggregate and of 80% slag replacement ratio to coarse aggregate had no problem with strength and freeze-1hw resistance. It is, therefore, judged that the product can be put to use. Less