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Abstract In order to solve difficult support problems of the large-span coal roadway under the second or multiple mining influence，an example of the working face 20108 ventilation roadway in Gaojialiang Coal Mine is presented. Through analyzing the engineering geological conditions and engineering rocks body characteristics，it is known that the roadway 20108 is the stress dilatancy expansion type composite geological soft rock. The damage mechanisms of roadway are the composite deformation mechanisms IABCIIBDIIIDA；and then the bolt-mesh-cable-grout with steel band coupling support design is put forward. By using the large finite difference program FLAC3D，numerical analysis of coupling support design is conducted. The numerical results show that comparing with non-coupling support，the plastic failure zone is obviously reduced and floor deformation is larger than roof deformation of coal roadway. The deformation of roof；and the floor and two working slopes are effectively in control. The field monitoring deformation of roadway surrounding rock shows that，deformation rates of roadway two working slopes under multiple mining influence are larger than those of the roof and floor，which indicates that deformations of two working slopes control the utilization function of ventilation roadway 20108. The results reveal that support effect of bolt-mesh-cable-grout with steel band coupling support is very good in large-span roadway under mining dynamic loads. Based on the theory of numerical calculation，the application of coupling support to large-span coal roadway under multiple mining influence is feasible；and the field monitoring result also verifies the validity and reliability of coupling support proposed.
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Received: 22 March 2013
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2014, Vol. 33 
