| The problems of energy and resource is major global issue, and building energy efficiency is the problem to be solved in the sustainable development of our country. During the manufacturing process, the cement not only consumed large amounts of mineral resources and energy, but also caused serious environmental pollution and resource waste. The creation of alkali-activated coagulation materials can cut down the consumption of energy and resources. In spite of this, it can also utilize industrial waste residue. With further research, the industrial waste residue take place of cement. Meanwhile, the variety of raw material gradually expand to the steel slag, phosphorus slag, red mud, fly ash, tailings and other aluminum silicate kind of industrial waste residue. It’s both scientifically and practically significant to study a new principle of the preparation of coagulation material.Slag and fly ash are better mineral admixtures and perform well in the concrete application. Because of its low activity and poor stability, the utilization rate of steel slag is very low. Most of steel slag is used as backfill material. in the process of hydration, steel slag and fly ash promote each other. The composite cementitious materials from steel slag and fly ash is to provide a new approach for alkali excitation material. In this paper, steel slag and fly ash are used as cementing material, and sodium hydroxide is used to adjust the modulus of sodium silicate to 1.2. Slag and fly ash, which replace cement is used for the preparation of mortar, concrete and so on. By the experiment of consistency and mechanics, to determine the optimal proportion and create crack-resistance front mortar. The main results are as follows:(1) The test for the flow of motar showed that the motar of steel slag and fly ash need less water than mortar of cement. The reasonable water/cement ratio is about 0.47. The compressive strength of 28d is 23.3MPa, the flexural strength is 4.2 MPa. Because of its low early strength, the strength of 7d is about 25% of 28d’s. The curing conditions have influence on the intensity, and the nature curing conditions can improve the performance of the alkali-activated materials.(2) By detecting the fineness of steel slag, study the effect of fineness of the steel slag activity. The steel slag discharged by Qingdao iron and steel plant is screened and ball milled to 298m2/kg. While the fineness of the level Ⅱ steel slag producted by Rizhao steel plant is 338m2/kg. The 7d’s cube compressive strength of motar is 18.8MPa, While 28d’s is 41.2MPa. The 28d’s flexural strength is 5.6MPa. Studies have shown that the more the fineness of steel slag increase, the larger the intensity is.(3) Steel slag and fly ash, instead of cement, are used as cementing materials for concrete. The 7d’s cube compressive strength of concrete is 13.7MPa, While 28d’s is 22.5MPa. The strength of 7d is 0.61 of 28d’s. The 28d’s Tensile splitting is 1.6MPa. By detecting the strength, determine its basic mechanics performance and provide theoretical basis for making concrete artifacts.(4) Aiming at solving crack problem of common mortar, crack-resistance front mortar was developed, the influence of polymer powder and polypropylene fiber on compressive strength and split strength was reached. The optimum water/cement ratio is 0.46, and sand/cement ratio is 1:1.5. Because of reducing ratio of presssive strength/bending strength, fiber and polymer powder can improve its crack resistance and flexibility. Analyse the application value of alkali-activated steel slag and fly ash anti-crack mortar from the aspects of economic cost. Alkali-activated steel slag and fly ash anti-crack mortar can reduce 11.7% than cement mortar. |
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