Theory And Practice On Intensified Mining Of Thichness Broken Orebody In Deep

Xincheng Gold Mine has mostly collected the Shallow ore bodies, and turns to mine the deep V#ore body after mining nearly40years. The whole section once blasting caving afterwards filling mining method is proposed according to the mining technological conditions of V#ore body by the quality level of engineering geological investigation and the test on rock mass quality grade of V#ore body, and obtain the technology of preliminary support of large span stope support around the cross-section method and safety monitoring. At the same time, the segmentation cutting courtyard once blasting, stope outline controlled presplit blasting and the sublevel stope blasting caving three blasting technology are solved. In the end, Xincheng Gold Mine realizs the safe, highly effective and low cost mining.Thirdly, the evaluation system of rock mass quality of underground stope was improved by the author of this paper, according to the seven evaluation index,which including compressive strength, rock quality designation, joint spacing, structural plane conditions, underground water conditions and impact factor of ground stress, the rock mass quality of V#orebody was evaluated as third stage,stope roof should be supported in advance while using the method of sublevel open-stope succeed by fill, at the same time,numerical calculation was adopt to obtain the stope span is8-10m.Secondly, according to the demand of advanced roof support, the analysis technique of time sequence prediction was used to monitor the safety of stope roof support. The support pattern was obtained by calculation which shows the advanced roof support stope should unite prestressed resin anchor, steel belt, metal net and gunite, the length of prestressed resin anchor is2.6m, the best anchor space is1.2m. Roof Strata displacement and anchor axial force was monitored, the prediction model and analysis technique of roof support safety time sequence was established to ensure the safety of stope roof.It is proposed that a mining method of the whole sublevel pre-splitting extrusion blasting again. The orebody is divided into stage in which of sublevel mining with trackless mining quasi of pulse sublevel roadway and concentrated ore chute in the mining method. Cutting engineering is built through constructing roof presupporting road and cutting across vein and deep hole blasting forming cutting patio. In stoping,the whole sublevel once caving and concentrated ore removal and concentrate filling are achieved by means of presplitting blasting and squeeze blasting, taking roof presupporting road as stope roof support and downward sublevel drill road, taking cutting patio as free surface, taking roof presupporting road and cutting across vein as compensation space.Finally, the fast recognition technology of millisecond blasting blind shot is proposed. Aiming at the difficulty to identify the millisecond blasting blind holes and its subsequent huge damage, an innovative rapid identification technology in use of the blasting signal energy mutation blind shot is put forward, which can determine the blasting time of each detonator by means of real-time analysis of blasting vibration signal. It can also determine whether or not there are blind shots and their general location by comparison of different delay time of each detonator.