Rock Mass Bolting in Coal Mine Workings for Floor Heave Control

This article addresses the problem of floor heave in preparatory mine workings of the Karaganda Coal Basin and proposes technological solutions based on rock mass anchoring systems. Long-term field observations, supported by analytical interpretation and numerical modeling, made it possible to identify the principal factors controlling deformation processes around mine roadways, including floor rock fracturing, stress redistribution during longwall mining, and the interaction between adjacent workings. Special attention is given to the performance of different types of anchors installed in the floor and to their optimal arrangement depending on the width and geometry of the excavation cross-section. Empirical relationships are proposed for estimating the magnitude of floor heave and determining the required anchor length, and their applicability is supported by numerical simulations performed using RS2 software v. 11.027. Based on the results obtained, technological schemes aimed at reducing the intensity of floor heave and improving the stability of the surrounding rock mass were developed for mining in inclined and gently dipping coal seams. Field experiments conducted in the Kazakhstanskaya, Saranskaya, and Abayskaya mines of the Karaganda Coal Basin confirmed the effectiveness of steel–polymer anchors in stabilizing excavation contours.