Study And Application On The Technology Of Gob-side Driving In Wanglou Coal Mine

This paper studies and analyzes the deep coal seam along the goaf retaining roadway mine pressure appearance,roadway side support and surrounding rock deformation,damage and movement law,along the goaf retaining roadway supporting mechanism,study and formulate the precast concrete block wall of wall of wall roadway side support along the goaf retaining roadway,put forward the roof control method along the goaf retaining roadway,based on the 3#coal seam nining in Wang Lou coal mine as the engineering background,According to the Wang Lou mine 3 coal seam pressure step distance of 45 m for the first time,calculate the size of the gob-side entry retaining lane side support resistance is 15.5 MPa,can choose the strength grade of C30 concrete;13301 working face lane side support wall height design is 2.4 m,with 100 mm deformation space,width design is 1.2 m..Put forward three kinds of retaining wall position scheme,the final wall part is located in goaf;The wall body adopts lengthened and thickened concrete blocks,and the structural form is a rectangular straight wall built by staggered joint longitudinal yards;The mass ratio of cement:medium sand:gravel:water is 1:0.54:1.6:2.98.Three types of blocks with different length × width × thickness are designed,and C30 reinforced concrete precast blocks are selected,and the preparation process is given.The masonry process of concrete block wall is put forward as follows:base leveling? wall setting-out?Preparation of mortar?making skin rod,hanging line?block arrangement?laying mortar?block in place?eorrection?vertical seam grouting mortar?jointing.The treatment measures to ensure the stability of wall are formulated.During stoping,the roof control of gob-side entry retaining adopts " one-beam" with single support mode,and the rear support of end support frame adopts two-way ?-shaped steel lifting shed support;During the stay lane mainly adopts bolt,anchor cable roof and roadway help reinforcement;In order to test the stability of the wall along the gob-side entry retaining wall,the internal stress of the pillar along the gob-side entry retaining wall in 13301 working face was monitored.The results show that the state of 3m measuring point shows that the pillar along the gob-side entry retaining wall is in elastic state,and the stability of the pillar along the gob-side entry retaining wall at least greater than 9m,i.e.15m measuring point is acceptable after mining.The depth stress value of other measuring points remains basically unchanged,and the influence depth of the working face pressure on the pillar side of the gob-side entry retaining wall cannot reach the measuring point.