炭鉱における坑道盤膨れに関する実験研究

Abstract

An important problem in the coal mine industry today is the roadway swelling, while it was not yet studied till today in Japan. In this article the authors examine the phenomenon of floor swelling in mine roadway experimentally.Many results were obtained by our scale model experimental studies to investigate the influence of a number of factors upon the swelling. These factors include applied pressures corresponding to the depth of roadway floor from the surface, mechanical strength of the floor strata rock and roadway width.The typical results which were obtained are as follows1) When the roadway width equal 2.80m and the swelling is relatively small, the maximum horizontal displacement point is located at the depths of 50-80cm from the floor surface. While in case of larger swelling, that point is located at the distance place from the side of roadway.2) When the other conditions maintain constant, the most deep point, where the horizontal displacement becomes zero depends neither on the roadway width nor on the moisture content of floor strata and is located just under the side of roadway.3) When the roadway width becomes wider, the vertical displacement of the floor surface decreases but converselly the displacement area increases at the center of roadway.4) If the swelling is allowed to 50cm at the center of roadway, the floor strata strength (cohesion, the angle of internal friction) which do not reqiure to dinting at the depths of 350 and 440m are 3.7kg/cm2, 19°20′ and 4.6kg/cm2, 23°40′ respectively.