NTIS: PB/243-899 Available for Reference At Bureau Libraries :124 pages
Criteria were developed for the design of roof bolt systems for coal mine roofs cut by fractures or intersecting joints. The problem was studied by mathematical finite element models and by laboratory models. Equations were developed to express relationships of such factors as horizontal formation pressures, inclination, and friction of joints, bolt loads, roof spans, and rock properties.
CP; Final Contract Report;
NTIS Accession No.
NTIS: PB/243-899 Available for Reference At Bureau Libraries
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