Damage Data Analysis of Deep Coal Roadway Roof and Application of Long Anchorage and Zone Linkage Support Technology

Abstract

China’s energy structure mainly depends on coal resources, which will still play the dominant role in economic development in the future. With the mining depth increasing, the deep roadway construction will be exposed to a complex stress environment, increasing the difficulty of roof control and further hindering the mining activities. The problem of deep roadway excavation causing significant fracture scope of surrounding rock in and outside the anchorage zone has attracted much attention. For the large crack scope existing in the roadway roof of deep underground openings, this paper focuses on the exploration of upgrading the support system. In order to solve this problem, we investigated the zone damage of the roadway roof with the discrete element model using the UDEC trigon method and damage quantified evaluation with data analysis. The long anchorage and zone linkage support technology was proposed based on the damage control effect of varying lengths of supporting bolts. The purpose of extending the length of bolts is to link the more severely damaged rock mass in the shallow part to the minimum damaged part in the deep place, aiming to form the thick anchor zone to mobilize the rock mass in each zone to participate and bear the load together. Furthermore, the onsite application of long anchorage and zone linkage technology gained good control effects in the selected typical roadway with different geological conditions. The results show obvious resistance in cross-section shrinkage, integrity maintenance, and minimization of crack scope in the roadway roof. The promotion of long anchorage zone linkage technology can help the mine with similar situations uplift the efficiency of working and guarantee the safety of miners during mine service life in the deep coal roadway.

Failure properties of roadway with extra-thick coal seams and its control techniques

“…Therefore, the deformation and failure characteristics of top coal in extra-thick coal seam roadway and its control technique need to be further studied. In recent years, the high preload and thick anchorage support technique [ [23] , [24] , [25] , [26] , [27] , [28] , [29] ] has provided a new solution for the stable control and efficient excavation of thick top coal in the mining roadway during the extra-thick coal seam mining.…”

Research on a Non-Synchronous Coordinated Reduction Method for Slopes Based on the Hoek–Brown Criterion and Acoustic Testing Technology

“…The mechanical parameters of the slope rock mass need to be determined before the slope stability analysis, and the deformation parameters and mechanical behavior of the rock mass are the basis for the implementation and safety assessment of all kinds of geotechnical engineering projects, being thereby related to the construction of engineering projects, economic benefits, and safety [37,38]. A widely used empirical estimation method is the Hoek-Brown criterion, which integrates various structural features describing the deformability and strength of a rock mass [39,40], where the important parameters to be estimated are the geological strength index, GSI, and the disturbance factor, D. The estimation method was also provided by Hoek et al [41,42], who also plotted its conditions and range of use.…”

Review on Improvements to the Safety Level of Coal Mines by Applying Intelligent Coal Mining

“…In addition, the mining depth is extended at an average rate of 10-25 m per year [8,9]. Deep underground, the working conditions deteriorate sharply, including high geo-stress, geo-temperature, karst water pressure, and gas content.…”