The Study On Creep Characterics And Supporting Of Surrounding Rock In Soft-floor Roadway Of The 13 Coal Seam In Da’anshan Coal Mine

The surrounding rock of roadway controlling has been one of the most technical problems which affect the safety and efficient production of coal mines,the soft rock roadway supporting is more and more serious,especially in the deep high stress environment.The developed folded structure,complex geological conditions in Da’anshan mine field,exists low intensity,high expansibility strata of sandstone of mud quality in the bottom of steep seam zone,brings great difficulties in roadway supporting,therefore,aiming at the high stress condition of steeply inclined coal and rock structural characteristics of soft bottom hard top,to reveal the reason of instability,the establishment has important theoretical significance and practical application value of scientific and effective support system.By reading a lot of relevant literature and collectied information,counted and summed up the deformation and damage characteristics of soft rock roadway,also the corresponding supporting measures,this paper sumed up the geological characteristics and deformation and failure of soft-floor roadway of 13 coal seam in Da’anshan coal mine.Specimens’ physical and mechanical parameters and mineral elements of soft-rock floor were tested.The distribution characteristics of stress field was analized.Three axis compression creep test were carried out for the roof sandstone and floor mud sandstone.The creep law was obtained and CVISC creep model was selected to describe the creep behavior.The creep model parameters were determined by using the L-M methord combined global optimization algorithm based on 1st-Opt software.The CVISC creep model of FLAC30 was used to analize the soft-floor roadway damage law of 13 coal seam in Da’anshan mine.An improved creep control scheme was proposed and numerical simulation was carried out,and the optimal second support time was determined.Aiming at the occurrence characteristics of soft-floor roadway of 13 coal seam in Da’anshan coal mine,the paper designed the roadway surrounding rock creep control technology based on the results of this paper.