The Research On Supporting Technology Of Coal Gateway With Weak-roof And Weak-coalin Outburst Pitched Seam

The occurrence and mining condition in outburst pitched seam are much more complexthan what they are in gently inclined seam. In the process of exploiting pitched seam, the realproduction will be greatly affected by the destabilization of gateway with weak-roof andweak-coal. In order to ensure the productivity and safty of mining in outburs pitched seam,we are in urgent need to do research on techniques of such entry support.On investigating and analyzing the real supporting conditions of outburst steepcoal-seams in Liziya-Nanerjing. Through researching into the surrounding's fundamentalmechanical properties of this gateway, this paper put forward an conclusion, which is aboutthe surrounding rock's characteristic derived from coal and rock sample mechanics testing.The paper also results the inherent technical difficulties points of roadway surrounding rock,which show that the supporting parameter of Liziya-Nanerjing colliery is influenced by theseam of coal and methane outburst, friable property of weak-roof, weak-coal,excavation bydrilling and blasting and former supporting method, outburst prevention and control measures.Then studying on five different supporting scheme according to the different geologicalcharacteristics and supporting reinforcement requirements. On utilizing the loadingable solidphysical simulation testing device, this paper completes the analyses of displacement anddestruction laws, the characteristics of internal distortion variations and surface dislocationchanges. The displacement and destruction laws, which are under the environment of dynamicloading, are about the overburden stratum and about the surrounding rock's damage andevolution. After analyzing the validity of supporting schemes with FLAC3D, the paper draws anatral conclusion that the combination supporting technology of bolting shotcreting and wiremesh with steel strip additional big bolting washer and framed gateway support is the mosteffective way to support the entry with weak-roof and weak-coal in outburst pitched coal-seam of Liziya-Nanerjing, and has been successful practiced the engineering application.The paper will play an important role in controlling the coal gateway with weak-roof andweak-coal in outburst pitched seam, and have referential significance of surrounding controlingand entry supporting with similar geological characteristics.