SU1364743A1 - Method of forecasting shock hazard of rock body - Google Patents

Abstract

This invention relates to the mining industry and the me. used in hazardous fields to predict impact hazard. The goal is to increase the accuracy and efficiency of the forecast by taking into account the change in the stress state of the array under the action of tectonic forces. In the implementation of the method, mobile tectonic units (TV) are identified in the rock mass and the zones of influence of their contacts are established. In each TB, outside the zone of influence on neighboring TB and within the zone of influence of the contacts of mobile TB, the resistivity of the rocks is measured. Assessment of the impact hazard of a separate TB is made by the ratio of its ES outside the zone of influence on it, related TB, ES of neighboring TB and ES at the contacts of this TB with neighboring TE of rock mass. TB is considered the most dangerous because it has the maximum value among the defined ratios of its ES outside the zone. They affected neighboring TB, ES of neighboring TB and ES at contacts of this TB with neighboring TB of the rock mass. 1 il. S (l

Description

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The invention relates to the mining industry and can be used in hazardous fields to predict impact hazard.

The purpose of the invention is to improve the accuracy and efficiency of the forecast by taking into account the change in the stress state of the array under the action of tectonic forces,

The drawing is a diagram explaining the proposed method.

The diagram shows the openings 1, located outside the zone of purification works. Movable tectonic blocks 2 borders 3 blocks, zone 4 influences contacts between the blocks, plot 5 of the electrical resistivity along one of the openings crossing several blocks, р,, рг ,. .., P l average elect

resistance in individual blocks

 , P, e. - average electrical resistivity near contacts with block 1

The method is carried out as follows;

In the zone of flow 1, located outside the zone of purification works, geological data and long-term measurements of electrical resistances are used to separate the movable blocks 2 of the array in the host rocks and determine the boundaries of blocks 3 and zones 4 of the influence of contacts between the blocks. Within the zones, the largest amplitude of change in the resistivity of rocks is observed. When the interaction between the blocks increases, the electrical resistance values near the contact are 3-5 times lower than the electrical resistance of any of the interacting blocks until the strength of the rocks at the contact between the blocks is reached. If there is no interaction between the blocks, the electrical resistance near the contact is greater than the electrical resistance of any of the blocks due to the fact that rock material at the contact between the blocks is usually broken by mycracks, which can open if there is no interaction between the blocks, which leads to a sharp increase in electrical resistance contact blocks. Measurement of electrical resistances is carried out on the walls of high current by the LAS method with a spacing of electrodes, corresponding to the depth of measurements beyond the zone of the reference generation pressure, i.e.

AB

half-feed electrodes

must be greater than 5 m. A graph of the electrical resistivity is plotted for each output, determining the average electrical resistance for each allocated block and for each contact between the blocks. As a criterion for the shock-hazardous state of the blocks, a state is taken in which the electrical resistances of the two adjacent blocks differ by an order of magnitude. Impact blocks are installed from

to p

R

im

. P kirn

where K, is the indicator of shock hazard of the i-ro block;

n is the number of neighboring blocks surrounding the i-th block;

bPjr

five

0

the difference in electrical resistance between adjacent i and m blocks;

R. - electrical resistance in the zone of influence of contact between the i and m blocks.

The most dangerous block is the block with the maximum value, K). The increase in the degree of impact with time corresponds to an increase in K: when measuring electrical resistances at different periods of time.

Claims (1)

Invention Formula A method for predicting the impact hazard of an array of rocks, including the measurement of the electrical resistance of an array rocks beyond the reference pressure of the workflow in the host rocks, assessment of the impact hazard of the rock mass by them, characterized in that, in order to improve the accuracy and the efficiency of the forecast, by taking into account the change in the stress state of the array under the action of tectonic seeps, in the rock mass, there are mobile tectonic blocks, zones of influence of contacts of these blocks, electrical resistivity of rocks is measured in each moving tectonic block outside the zone affected by neighboring blocks and within the zone of influence of contacts of movable tectonic blocks; the impact rating of an individual block is estimated by the ratio of its electrical resistance outside its neighboring blocks. t