Rock massifs in mountainous folded regions which have their specific structure, morphology of ore bodies and tectonics are marked by significant geomechanical heterogenity. It is found that stresses in highly fissured areas of mountainous folded regions are on 25–30% lower and in stabilized low fissured are on 50–60% higher than values, characteristic for average conditions in mountainous regions.

The problem of stressed condition of rock massif is one of the most complicated in mechanics of rocks. It is especially urgent for rock massifs in folded areas where the substantial structural geological and petrographic distinctions form a very complicated geomechanical situation. On the basis of generalization of long standing research it is established that the spatial periodicity of mechanical parameters of rocks changing is characteristic for the rock massifs of folded areas [1). The main laws of Spatial changeability of rock mechanic properties discovery in massif was based on the selection of kern samples in every 20–50 sm from the specially drilled holes 5–20 m deep. It was also based on their mechanical properties determination and the construction of graphics of these properties changeability along the holes. The research showed that in all the cases the obvious Spatial periodicity of mechanical rock properties changeability is observed. As an example in fig.1 the graphic of changing of modulus of elasticity of rocks in Sumsar deposit along the hole is shown. For every part of massif the Wavelengths are in similar ranges. In the whole we can note that the period of changing of mechanical properties of rocks along any direction in different rocks and massifs change from 0.3–0.4 to 3–4 metres. It was discovered that in the same rocks in different parts of the deposit which differ in the degree of cracks, parameters of spatial changeability of mechanic properties are different. The results of these experimental researches are supported by the geomechanical test of massif in natural conditions with the help of BP-18 unit, the application of which is based on the method of statistic forcing down the hard stamp (indentor) into the grounded face of the hole. We carried out our research in spot test of the massif in every 10–20 sm of holes 5–6 m deep on every experimental part with the help of three parallel holes 25–60 sm apart from each other. We forted the results in the graphic dependences of changing of failing efforts of forcing along the hole. As a result of statistic processing of data on stress measure in ore deposits massifs of folded areas. It was discovered that both in magmatic and metamorphosic rocks of different ore deposits variation of contact strength of rocks along the hole has a periodical character caused by block structure of massif. Parameters of the waves correspond to those meanings that we got when the area was tested with the help of selection and mechanical testing of kern samples. Rock massifs of ore deposits in Central Asia and South- East Khazakhstan are devided to primary blocks 0.20–0.70 m.

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