Construction technology of green concrete

Abstract

The invention discloses a construction technology of green concrete. The construction technology is characterized in that commercial concrete is delivered to a working surface by a concrete delivery pump and a concrete delivery pipeline; a stone storage silo is mounted above an opening between the tail end of the delivery pipeline of the commercial concrete and an inlet of a helical mixing delivery device; a rotational impeller is arranged at the lower end of a feeding opening of the stone storage silo; extra stones are added from the feeding opening, and are automatically distributed to the flowing commercial concrete by employing the rotation of the impeller driven by the flowing inertia of the flowing commercial concrete; and the extra stones and the flowing commercial concrete are mixed uniformly by the helical mixing delivery device to form the green concrete to be delivered to a spreader pipeline for spreading and pouring. Compared with a construction technology of the conventional commercial concrete, the construction technology of the green concrete has a series of advantages as follows: (1) phenomena of drying shrinkage and cracking are reduced greatly; (2) the green concrete has excellent mechanical property; (3) the volume stability is good; (4) the cement usage is saved to a great extent; and (5) the pumpability of the commercial concrete is not affected.

Description

technical field [0001] The invention relates to the development and application of new concrete materials and the technical field of concrete construction. Background technique [0002] At present, high-performance pumped commercial concrete is the most widely used in various construction engineering fields. With the rapid development of my country's economic construction, about 3 billion cubic meters of commercial concrete is consumed every year. Pumping commercial concrete has many advantages such as high degree of mechanization, strong conveying capacity, strong mobility, can speed up construction, save time and labor, and save construction period. However, in order to enable commercial concrete to have long-distance transportation and pumping capabilities, commercial concrete needs to have good fluidity. Concrete slump is a commonly used index to reflect the fluidity of concrete. The required range of pumped concrete slump is 180mm-220mm to ensure that the concrete can ...

AI Technical Summary

Problems solved by technology

However, if the mix ratio of commercial concrete is adjusted to increase the stone content in concrete, the slump of concrete will be reduced, and the fluidity will be poor, which cannot meet the pumpability requirements of commercial concrete.

If the mix ratio is readjusted so that the commercial concrete contains a large proportion of stone materials and can meet the slump requirements of pumped concrete, the water content has to be increased, resulting in an excessively high water-cement ratio, which affects the concrete. strength, while excessive water content will lead to more serious shrinkage cracking

In short, in the preparation process of ready-made concrete, increasing the mixing ratio of stone and increasing the slump of concrete are a pair of contradictions. In other words, it is impossible to meet the pumpability requirements of concrete while adding a large proportion of stone.

Therefore, up to now, the method of enhancing the cracking resistance of concrete by increasing the proportion of stone mixing cannot be realized in pumping commercial concrete projects.

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