急速加圧時の石灰，きょう炭層岩石の温度変化

Abstract

Gas pressure and rock pressure in coal seams are related to the occurrences of a gas outburst. Prediction of a high stress zone in advance of mining enables the selection of a proper countermeasure against a gas outburst, but it takes much time and cost. to measure the underground rock pressure with the mining operations and it is not practical.In come countries the temperature is measured in order to judge the high stress zone in a coal seam. There are two contradictory ideas about the relationship between temperature and stress in the coal seam; one being that the temperature increases in accordance with the increase of stress, and the other one being that the temperature decreases in accordance with the increase of the stress. These contradictory thoughts come from the following reasons. The temperature rise caused by the stress rise has two reasons. The first one is caused by the direct adiabatic process in coals and rocks and the second one is caused by the low temperature oxidation at the high stress zone where many cracks are generated by the high stress, when the high stress zone is near the surface of the coal seam and the air flows into these cracks. The temperature decrease by the stress rise comes from the gas release from pores in the coal seam having high gas content and gas pressure to the cracks which are generated by the high stress.To get the fundamental data of the relationship between temperature change and stress change, the author measured the temperature of the coals and rocks obtained in Japanese coal mines by changing the surrounding pressure up to 34 MPa for the confining pressure and the uni-axial compression.The temperature rise was 0.22-0.46°C/10 MPa for the coals and 0.07-0.25°C/10 MPa for the rocks under confining pressure. These values were too small to apply the measurement of temperature change for the proper prediction of a high stress zone.