Evaluating test drill results in coal seams - uses different types of coal as base for evaluation

摘要

The test drill results evaluation from coal strata indicates the risk of a rock burst. The drilling spoil from the test is measured in lit/m of drilling and by forming quotients for the actual and theoretical value of the amounts of the spoil, together with the incorporation of strata reactions, results are obtained. they are evaluated in accordance with the type of coal in question pref. composition is included, partic. the proportion of vitrain in coal for the typical evaluation. ADVANTAGE - No need for complicated measures and for stress relief or even work stopages