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

本研究以分解后的花岗岩、中国砂、城市生活垃圾气化炉渣和废玻璃碎石作为混凝土细集料，研究了新拌混凝土和硬化混凝土的性能。在此基础上，采用三种不同坝址来源的三种分解花岗岩进行混凝土配合比和坍落度8 cm的配制。受检者。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，分解花岗岩混凝土的缺点是(1)坍落度随时间损失较大，(2)泌水几乎为零，(3)凝结时间较普通混凝土短，可改善至与普通混凝土相当的物理性能。…采用缓凝型引气型高效减水剂，提高了普通砂的抗压强度。研究二，探讨了国产砂和工业废渣细粉作为混凝土细集料的有效利用。首先，将碎砂、河砂和两种中国砂混合制成三种类型的细骨料，并研究其类型对混凝土性能的影响。其次，由于中国砂中含有少量0.15 mm以下的细粉，所以在中国砂中掺入0.15 mm以下的细粒粉。选用的细粉有碎石微粉、镍铁矿渣微粉、玻璃微粉、干泥粉和两种石灰石粉。考察了细颗粒类型对混凝土性能的影响。试验结果表明，掺中国砂的混凝土粘度差、渗漏量大，除镍铁矿渣细粉外，其他细粒均能改善这些不良性能。研究三考察了两种气化城市生活垃圾渣(MSW)矿渣用作混凝土细集料和粗集料的可能性。显然，由于所选的城市生活垃圾渣满足混凝土用细集料的质量标准，因此可能性很高。矿渣取代率为细骨料的50%、矿渣取代率为粗集料的80%的混凝土制品的强度和抗冻性均不存在问题。因此，可以判断该产品可以投入使用。较少

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