Study On Stability Analysis And Control Technology About Roadway Driving Along Goaf At Fully Mechanized Top Coal Caving

The long-term stability control of surrounding rock was the key to roadway driving along goaf with fully mechanized top coal caving. In the paper, driving roadway along goaf and the main roof were the research objects, system analysis about the stability of driving roadway along goaf and the control technology by theoretical analysis, numerical simulation and industrial test research method, etc, the key analysis was stability of key block B, the main influence factors of the gob-side entry, the main roof fracture structure. Innovative achievements of this dissertation have been displayed as follows:(1)Based on the stress distribution of key block B in gob-side entry, we have set up a basic mechanics model, then analyzed the fracture line of main roof located on outside of the narrow, the top of the roadway, inside of the roadway, there were eight kinds of stress distribution and the stability of key block B, in the end, we mastered the different fracture line’s positions influenced at the stability of key block B.(2)The study indicated there were four main impact factors of main roof on the stability of gob-side entry’s surrounding rock were the height of main roof, fracture structure of main roof, the length of B key block, the intensity of main roof.(3)The stability of gob-side entry closely related to the height and the fracture lines of main roof. With the height of main roof increased, surrounding rock’s deformation of roadway increased. When the fracture line of main roof locates just at the top of the roadway, the deformation was the biggest. When the fracture line of main roof located outside of the pillar, if the height was 0m, the deformation was the minimum. When the fracture line of main roof locates inside of the coal wall, if the height were 5m、10m, the deformation was the minimum. So the roadway should be layouted inside of the fracture line of main roof, and it should be avoided to layouted under the fracture line of main roof.(4)Roadway supporting should be considered the fracture line’s positions influenced on the stability of the gob-side entry, and according to the stress concentration degree of surrounding rock to choose the parameters of bolting.(5)Engineering effects indicate that the width of coal pillar was reasonable, the fracture line located over the coal pillar and closed to the goaf, supporting could effectively control the deformation of surrounding rock, these effect conformed to the requirement of mining face, and gained satisfactory result of the technology and economy.