doi:10.16186/j.cnki.1673-9787.2020050061

Received:2020/05/21

Revised:2020/09/04

Published:2022/03/15

Experimental study on the seepage evolution model of coal floor subsided karst collapse column

JIANG Quanle 1, ZHANG Boyang 2, HAO Ming 1

1.Yulin Shenhua Energy Co. , Ltd. , Yulin 719000 , Shaanxi, China, Henan Polytechnic University, Jiaozuo  454000 , Henan, China；2.School of Civil Engineering, Henan Polytechnic University, Jiaozuo  454000 , Henan, China

Abstract: The water inrush from the coal seam subsided karst collapse column has the characteristics of concealment and suddenness,which is an important hidden danger in the safe production of coal mining in North China.In order to solve this kind of production safety hidden danger in coal mine,the self-developed model experimental system of the seepage evolution mechanism was developed for the experiment of the water inrush from the coal seam subsided karst collapse column,and three groups of samples with different collapse column were prepared.The seepage key parameters such as start water pressure,pore water pressure,flow velocity were tested,the relationship of water pressure-flow velocity and pore pressure-diffusion radius were analyzed,and the non-Darcy flow characteristics analysis were carried out.The results showed that: The starting water pressure gradient of the model test was between 0.60 and 1.57 MPa/m; The water pressure-flow velocity and pore pressure-diffusion radius all showed the characteristics of non-Darcy flow; The hyperbolic form was used to fit the variation curve of pore water pressure coefficient with the diffusion radius; The non-Darcy flow β factor of model test was all negative.

Key words:coal floor;karst collapse column;model experiment;pore pressure;diffusion radius;non-Darcy flow