Foam filling body for coal mine goaf filling and preparation filling method of foam filling body

Abstract

The invention provides a foam filling body for coal mine goaf filling and a preparation filling method of the foam filling body and belongs to the technical field of coal mine goaf filling and underground construction engineering. The foam filling body comprises the following ingredients in parts by weight: 60 to 70 parts of coal ash, 20 to 40 parts of cement, 20 to 45 parts of water, 0.2 to 0.6 parts of water reducing agents, 0.4 to 1.6 parts of coagulation accelerators and 0 to 20 parts of active agents, and the volume percentage ratio of foam to gelling slurry is 100-250 percent. The gelling slurry solidification time of the filling body is about 3 to 4 days, the single-axis stress intensity is 0.5 to 1.7MPa after 28 days, the apparent density is 650 to 940kg / m<3>, the pumpable time is 11 hours, and the heat conductivity is 0.255 to 0.376 W / (m.k). The foaling filling body can be used for the coal mine goaf filling and has the beneficial effects that the coal ash consumption of the foam filing body is obviously increased, the preparation is simple, the cost is lower, the functions of light weight, cracking resistance, heat insulation, seismic resistance and the like are realized, the on-site application prospects is wide, and obvious economic benefits are realized.

Description

technical field [0001] The invention relates to a foam filling body and a filling method for filling goafs in coal mines, and is mainly suitable for filling goafs in coal mines, filling in underground engineering and using in anti-seismic layers. Background technique [0002] my country is a large country of coal consumption and production, and long-term coal mining has formed a large area of ​​underground gobs. At present, the most direct and effective method to cure surface subsidence and mining damage is goaf backfilling. For a long time, the main technologies used at home and abroad include three methods: dry filling, water-sand filling and cemented filling. Among them, the cemented filling goaf method has high strength after cementation, which can significantly reduce the use of raw materials. It can also be used for medium-thick ore bodies with deep burial, high ground pressure, and unstable surrounding rocks. The use of cemented filling has become a coal mine. The i...

AI Technical Summary

Problems solved by technology

The amount of cement used in the traditional cement-bonded filling body is large, which increases the cost per ton of coal

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