Experimental Study On Early Strength Of C60 Precast Concrete

The density of concrete is high, if we want to produce high precision which meet the requirements of precast, preferably with a combination of steel formwork. But investment costs combined steel formwork is high, since the major template of how to improve the recycling rate is related to a company’s economic benefits. Through a series of mortar and concrete test group developed a high early strength, good workability C60 concrete mix, improve recycling rate template.In this study, first select seven different plaster, mortar through a single experiment, one group elected the best plaster-Shijiazhuang, a company Hemihydrate (B1). The preferred dosage of gypsum binder set at 10%, the amount of cementitious material is 450 g, sand to 1350 g, test variables slag, NaOH, water reducer, defoamers, mortar mobility, flexural strength, compressive strength test. Then by mortar four factors and three levels orthogonal experiment, the optimum mixture ratio of mortar:Hemihydrate 8%,5% superfine mineral powder, defoamers 0.1 g, poly-carboxylic acid 0.25%. Finally, in order to study factors affecting the C60 concrete early strength, but also made orthogonal test results, a set of optimal concrete mixture ratio: Hemihydrate 8%,5% superfine mineral powder, defoamers 2 g, polycarboxymethyl acid 0.45%, early strength agent 2%, NaOH 15 g, this time corresponding water-cement ratio of 30%.The issue will come up with concrete mix being applied to the production of ready-mixed concrete, can be recycled to improve early strength and formwork for concrete, reduce production inputs, increase economic efficiency.