Study On Soft Surrounding Pressure Behaviour Of Gob-side Entry Retaining And Support Parameters Optimization In Xinyuan Colliery

Based on research background of 3107 working face aided intake roadway soft surrounding roadway gob-side entry retaining in Xinyuan Coal Limited Liability Company, this paper which was applied the method of orthogonal experiment design and FLAC3 D numerical calculation, thoroughly studied the roadway deformation and filling body loads under the influence of thickness and strength of immediate roof、thickness and strength of the basic roof、pillar strength five factors and five levels and roadway mining pressure of soft surrounding rock, optimized the roadway-in supplement support parameters and roadside support parameters, put forward surrounding rock control technology aiming at soft surrounding rock and applied theoretical research to engineering practice. Main research results as follows:(1)Analysing the roadway deformation and filling body loads under five factors and five levels of thickness and strength of immediate roof、thickness and strength of the basic roof、pillar strength by orthogonal experiment design, determined primary and secondary relationship of five factors and five levels, optimized the scheme of raadway supporting.(2)Comparative analysis on characteristic of strata behavior among soft、medium-hard、hard rock conditions, highlighted the low carrying capacity、large deformation、large plastic zone range of soft surrounding rock.Based on this,we proposed the surrounding rock control design that strengthened vulnerable and weak support such as the roof of roadway 、filling area、the side of solid coal and angle area, single hydralic props were used to support the roof during the mining.(3)Analysing the roadway deformation and plastic zone under strength and width which were two factors and had four levers of filling body,by comprehensive experiment method, reached a conclusion that strength and width which were two factors and had four levers had a greater effect on the indexes of floor shifting and filling body horizontal displacement which were regarded as main indexes, and they had a smaller effect on roof displacement and pillar horizontal displacement which were regarded as referenced indexes. Basis on this, the optimal parameters were selected.(4)Research result is used in 3107 aided intake roadway of Xinyuan Colliery where we get a success. during the entry retaining period, the surrounding rock and filling body have been stable,which greatly improve the production efficiency.