Pouring material for mine

Abstract

The invention discloses a pouring material for a mine. The pouring material is prepared by mixing and stirring the following raw materials in percentage by weight: 17 to 19 percent of 42.5-level cement, 35 to 37 percent of medium sand, 34 to 36 percent of 3 to 5-millimeter gravels, 4 to 6 percent of II-level pulverized fuel ash and 3 to 5 percent of complex additive, wherein the complex additive consists of the following raw materials in part by weight: 12 to 15 parts of naphthalene-based high efficiency water reducing agent, 10 to 15 parts of amino, 0.05 to 0.1 part of hydroxyethyl cellulose, 0.5 to 1 part of sodium gluconate, 1 to 1.5 parts of citric acid, 5 to 15 parts of sodium acetate, 3 to 12 parts of potassium carbonate, 1 to 3 parts of lime, 1 to 4 parts of alum, 1 to 2.4 parts oftricalcium aluminate, 21 to 69.5 parts of carbonic acid tricalcium and 0.1 to 0.5 part of sodium carbonate. The pouring material can be demolded quickly, has a long conveying distance and a good filling effect, and is vibration-free. A pouring body has high later strength, and is mainly applied to pouring of a support wall body beside gob-side entry retaining under a coal mine.

Description

technical field [0001] The invention relates to a pouring material, in particular to a filling pouring material used in the side support technology of gob-side entry retaining in coal mines. Background technique [0002] Gobside retaining is an innovative technology in coal mining. It can increase the coal recovery rate, reduce the number of excavations, reduce the contradiction between excavation and connection, save coal resources, and improve economic benefits. my country has made a lot of explorations in the application of gob-side entry retaining technology. From thin coal seam to thick coal seam, from gently inclined coal seam to steeply inclined coal seam, there are successful experiences in gob-side entry retaining. The development process of its technology can be roughly divided into the following four stages. [0003] The first stage: Since the 1950s, wooden shed support has been adopted, and the thickness of the coal seam is required to be less than 1.5 meters. ...

AI Technical Summary

Problems solved by technology

Disadvantages: large amount of gangue settlement, serious deformation of the support in the roadway, heavy maintenance workload, low work efficiency of workers building gangue, high labor intensity, poor safety, etc., the scope of application is greatly limited

Disadvantages: Since most of the support in the roadway is passive support, and the filling technology beside the roadway is not perfect, its support technology is difficult to meet the requirements of large-section gob-side roadway retention, and the application range shows a decreasing trend

The roadside support and filling technology has also been continuously improved. Up to now, pouring materials with different raw materials, different proportions and different performances have been used in the gob-side retaining roadway to support and fill the wall. However, due to the different raw materials and proportions used, Its performance is also different, and the effect of pouring on the side of the road is also quite different. After some pouring, the strength of the entity in the later stage is low, and the thickness of the pouring body needs to be increased, resulting in waste of materials; Prolonging the demoulding time will affect the mining efficiency; some have earlier initial setting in the pouring process, and the slump loss is faster, which affects the conveying distance and pouring effect