Bulking coefficient evolution characteristics and mechanism of compacted broken coal
CHU Tingxiang
LI Pin
CHAO Jiangkun
YU Minggao
HAN Xuefeng
Abstract：Using the self-made testing device of coal seepage and spontaneous combustion of compacted broken coal,the evolution characteristics and mechanism of bulking coefficient of broken coal under different conditions of stress,stress-temperature,and stress-water were tested and analyzed.The results show that:① the bulking co-efficient of broken coal has obvious stage with the increase of stress,and the change rule of bulking coefficient under the stress meets with the negative exponent.② under the same axial compression,the bulking coefficient increases with the increase of temperature,and the thermal expansion effect is obvious,which indicates that the thermal effect of spontaneous combustion will increase the bulking coefficient and loose the accumulation of broken coal in gob.③ when the water content increases in vitro of the broken coal,under the same axial com-pression,the bulking coefficient increases with the increase of external moisture,which shows that the broken coal bulking coefficient will increase with the increase of water.④ under the action of stress,thermal expansion and wet expansion,the internal particles occur relatively moving in the accumulation body,secondary crushed and granular self-accumulation,which cause the stress-strain curve change,and the bulking coefficient affected.
Keywords：gobbroken coalbulking coefficientmultiple environment
Publication Date：2017-01-01