Self-compacting concrete and preparation method thereof

Abstract

The invention discloses self-compacting concrete, which is prepared by taking low air entraining polycarboxylic acid and polyacrylamide as additives, taking continuous graded mineral waste rock of 5-20 millimeters as crude aggregate, taking mine waste rock of 0-5 millimeters as fine aggregate and using high-volume fly ash and mineral powder with a secondary feeding method. In the invention, the air entraining polycarboxylic acid and a polyacrylamide flocculent are taken as the additives, so that the defects of poor segregation resistance and poor stone coating property of self-compacting concrete in the conventional technology are overcome, the internal pore volume of freshly-mixed concrete paste matrix can be reduced remarkably, the paste matrix is more compact, and the compressive strength of the concrete is increased remarkably. In the invention, mine waste rock is adopted for completely replacing concrete aggregate, so that the utilization ratio of the mine waste rock is greatly increased, the cement using amount is reduced due to the application of the polyacrylamide, and the cost of the concrete is lowered. The flowing property, self-compacting property, pumping property anddemolded concrete representation of a self-compacting concrete mixture are superior to the prior art.

Description

technical field [0001] The present invention relates to a kind of self-compacting concrete and its preparation method, especially to a kind of using Wick Mine waste rock to replace concrete coarse and fine aggregate, low air-entraining polycarboxylic acid and polyacrylamide flocculant as admixture and large amount of pulverized coal A method of preparing self-compacting concrete using ash and mineral powder. Background technique [0002] Self-compacting concrete (self-compacting concrete) mixture has better resistance to separation, filling and good performance through dense steel gaps. It is compacted by itself under the action of its own weight, and can be filled into various parts of complex shapes and dense-reinforced structures. After hardening, the concrete has good mechanical properties and durability. [0003] Self-compacting concrete has excellent working performance and excellent construction performance, especially suitable for concrete projects with various comp...

AI Technical Summary

Problems solved by technology

After 2000, 600 million tons of tailings were discharged every year. According to this calculation, the total amount of tailings is about 10 billion tons. The stockpiling of these tailings occupies a large amount of farmland and forest land and causes huge damage to the environment. Pollution

In order to maximize profits, cement production enterprises add more admixtures in production and need to clarify the specific reasons for the decline in cement quality. The deterioration of cement quality makes the concrete industry have to increase the amount of cement to ensure the quality of concrete. , thus increasing the production cost of concrete

Another problem currently in use is that the encapsulation of stones is poor, especially in the preparation of self-compacting concrete, this phenomenon is particularly obvious, and the workability of concrete is very poor

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