Digital Identification Of The Discontinuities Information And Strength Evaluation Of The Rockmass

In the study of mining engineering, geotechnical engineering, rockmass mechanics, the problems of rock mass stability is constantly encountered. Through persistent endeavor and exploration, human beings gradually realized that the destruction of rockmass engineering is controlled by various discontinuities in rocks. There are five classification classified by their development and scale. The discontinuities ofⅢ,ⅣandⅤclasses should be measured during the process of traffic, mining and hydraulic engineering excavation. These small scale discontinuities are widespread distributed in the rock mass, and they strongly impact the mechanics property and stress distribution in the rock mass directly. They usually determine the damage style of the rock mass in large extent, and the stabilization of the rock mass engineering are controlled by them. Therefore we must capture the development, distribution and assemblage of these kinds of discontinuities correctly and properly. It has become the basement and key point of the rock classification, capture of the rockmass mechanics parameters, optimize the design and construction of the rock mass engineering.The article is based on the present status which the discontinuities are mainly captured by human measurement contacting the rock at present with large amount of labors and low efficiency. Using advanced ShapeMetrix 3D digital photogrammetry measuring system, capture the information of these discontinuities in detail through measuring a large number of discontinuities on the surface of the rock.Using ShapeMetrix 3D system in the northwestern slope of the Dagushan iron mine, create three-dimensional solid model of the slope surface and get the geometric information of discontinuities and stereographic projection. Then do mathematical calculation of statistics for all kinds of geometric information of these discontinuities, and get the probability distribution model of the traces, dip angle and dip orientation. Simulate the inner three-dimensional distribution of the discontinuities of the rock mass with the method of Monto-Carlo, and provide strong foundation for maintenance and stabilization analysis of the slope.Capture the information of the discontinuities of the sandrock tunnel face from 12 coal seam floor in Fangezhuang coal mine with digital photogrametry measurement. Estimate the strength of jointed rock mass and get the mechanical parameters with modified generalized Hoek-Brown strength criterion.