High-water expansion filling material

Abstract

The invention relates to a high-water expansion filling material belonging to the technical field of buildings, water bodies and subway mining. The high-water expansion filling material is characterized by being slurry containing fly ash, an expansive agent, a retardant, an accelerating agent, a curing agent and water. The solid-liquid ratio is 1:1.2 to 1.5, the proportion is 1.35, and the expansion rate is 10-30 percent. The invention solves the problems of active pressing top-filling and long-distance gravity feeding in medium and thick coal beds and has very important meaning to the improvement of the domestic mining biological environment and the increase of the resource recovery rate.

Description

technical field [0001] The invention belongs to the technical field of coal mining under buildings, water bodies and railways (abbreviated as "three under"), and in particular relates to a high water expansion filling material used in coal mining by filling method. Background technique [0002] my country is rich in coal resources, the reserves rank among the top in the world, and large and small coal fields are spread all over the country. There are a large number of buildings, water bodies, railways, and high-grade highways above the coal fields, and there are problems of crushing coal in various mining areas to varying degrees. For a long time, the coal mining methods in my country's coal mines mainly adopt the methods of village (town) relocation, strip mining and filling mining. [0003] Among them, according to filling materials and transportation methods, mine filling and mining technologies mainly include the following types: [0004] 1. Dry filling: it is to trans...

AI Technical Summary

Problems solved by technology

Its shortcomings are: the filling material of hydraulic filling lacks cohesive properties, cannot form a stable and self-supporting filling body, and the stope needs a lot of dehydration

Its shortcomings are mainly manifested in three problems: 1) The filling material is difficult to connect to the top, and the filling effect is poor

Due to the poor fluidity of the paste or paste-like slurry, it is difficult to ensure uniform filling, especially after the slurry is cured and shrinks by about 30%, it is difficult to achieve the purpose of controlling surface subsidence

2) High transportation cost

Coal mine resources are not relatively concentrated in a small area like metal ore bodies. The range of plane extension is usually large, and the filling material needs to be transported over a long distance. The use of pumped paste or paste-like filling will inevitably increase the filling cost

3) The crushing cost of coal gangue increases the filling cost