Experimental Study on Water Absorption Performance of Super Absorbent Resin in Sealing and Grouting Process of Gas Drainage Hole

Abstract

In order to verify the possibility and reliability of water absorption resin as cement grouting stopper, the water absorption performance of water absorption resin in different slurry environments was tested. The results show that the water absorption ratio of water absorption resin in different liquid media is: distilled water > tap water > physiological saline > ordinary cement slurry filtrate > expansive cement of pulp filtrate; in the first five minutes, the water absorption rate of normal saline is the fastest. After five minutes of water absorption, the absorption rate of all kinds of slurries has reached more than 50% of their ultimate water absorption rate. In the first 10 minutes, the absorption rate of distilled water is the fastest. After 10 minutes of water absorption, the absorption rate of all kinds of slurries has reached more than 80% of their ultimate water absorption rate. After 13 days of water loss, the water retention rate of tap water is 77%, the cement slurry retention rate is 74%; the water retention rate is 77%. The larger the water cement ratio of the slurry, the slower the formation of the dry cement layer contacting with the absorbent resin. The dry cement layer hinders the transfer of water to the absorbent resin. The water-absorbing resin used as the stopping plug of drilling grouting can greatly reduce the compressive strength of the cement in contact with it, and the influence range is about 100 mm.

Keywords

• absorbent resin
• cement slurry
• water absorption
• compressive strength
• dry cement layer