The work presents the tests and considerations on roof control at caved longwall faces advanced under the strata composed of hardly workable rocks with the use of powered supports. A part of the supports in the process of caving and regulation of pressures in the strata of the immediate roof and solid coal ahead of the face is presented. On the basis of the obtained results the functional relationships were derived and diagrams for determination of a necessary value of the load—bearing capacity of the face supports were prepared to obtain the optimum conditions of mining and maintenance of the longwall workings.

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