Time deformations of the large openings in the rock salt mine

In the room and pilar method of rock salt exploatation it is necessary to invest!” gate the Theological behaviour of massif on the frame of a room. We must make the measurements on the different profiles in a very large room. It must be done because the differentdeformations on different places alog the longest axis of the room occur. Measurements, which are presented here, point out the high complexity of the measurements, and the measurements interpretation problems. The basic idea of this work is a presentation of the methods of measurement, characeteristic rea-suit obtained, and its presentation. We must to present a new view in the rheolo-gycal rock mass investigation in the large underground oppenings.