Abstract

Purpose. Research of deformation processes of protective structures of preparatory mine workings to ensure the stability of side rocks in the coal massif and preparatory workings in excavation areas in a coal mine. Methodology. To simulate the behavior of security structures under static load in laboratory conditions, experimental samples have been tested under conditions of uniaxial compression. Results. Rigid security structures (coal targets, BZBT bollards, cement blocks and cast strip) and flexible security structures (wooden bonfires and rolling bonfires made of wooden sleepers) have been considered. It has been established that under conditions of uniaxial compression of flexible security structures under the action of a static load, when the ratio of the potential energy of the change in shape Uф to the change in volume Uо is Uф/U0 ≤2.12, compaction of wooden structures (without loss of stability) and an increase in their bearing capacity, which makes it possible to limit the convergence of lateral rocks. For rigid protective structures, when Uф/U0 ≤4.1-6.5, there is a loss of stability of the supporting structures, a decrease in their bearing capacity, which eventually leads to the collapse of side rocks. The assessment of security structures in terms of stability, rigidity and bearing capacity should be based on the properties of the material of the supporting structures. Scientific novelty. Under the conditions of uniaxial compression, the functional dependence of the change in the specific potential energy of deformation of protective structures of preparatory mine workings on the coefficient of their transverse deformation has been established. Practical significance. To ensure the stability of side rocks in the coal massif during its unloading, it is advisable to use flexible protective structures.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call