METHOD FOR FASTENING WORKING Russian patent published in 1996 - IPC

FIELD: mining. SUBSTANCE: effective rock resistivity is measured by electric profiling at working surface after working face motion in unfastened space. Coefficient of crack permeability of rock, and decrease of design load on timbering are determined on the base of the value measured. According to decreased load design parameters are measured by a method as follows: increasing distance between timbering frames, decreasing mean distance between framework and working surface, decreasing strength of mortar. Then frame-like metal timbering, framework with injection pipes are installed. Injection plant is connected to the pipes and cement-sand solution is injected to the space between the framework and working contour. Water-cement solution penetrates to rock cracks to form cementation zone that forms additional bearing shell. EFFECT: steel-concrete timbering. 3 cl, 3 dwg