Theoretical framework and reliability verification of the loaded three-zone structural model in coal mine overburden strata

The fundamental stresses that determine rock burst in coal mine workings are primarily gravitational stress and tectonic stress, with the inducing force mainly coming from the stress generated by the structural movement of the overlying strata in the workings. The variable structural forms and movement patterns of the overlying strata are the main reasons for the complex mechanisms of rock burst and the various forms of impacts. By studying the relationship between the boundary conditions of the workings and the structure of the overlying strata, and based on mine pressure and strata control theory, a 'Three Load Zones' structural model of the overlying strata influencing the stress field of rock burst in the workings is proposed. The definition of the Three Load Zones and the subsequent computational model are introduced, and the differences between the 'Three Load Zones' and the traditional 'Three Zones' are explained. Using microseismic monitoring technology, the evolutionary characteristics of the overlying strata under mining conditions are studied, and the evolutionary patterns of the Three Load Zones are quantitatively analyzed. The influence of the 'Three Load Zones' on lateral and strike support pressure in the working face is also discussed. An estimation model for the 'Three Load Zones' stress is proposed, and the application of this theory in evaluating rock burst in the workings is analyzed. Through field measurements and applications, combined with theoretical analysis, microseismic monitoring, and numerical simulation methods, the validity of the proposed 'Three Load Zones' theory is demonstrated. This method can be used for the risk assessment and classification of rock burst in coal mine workings, providing a theoretical basis for targeted mitigation of rock burst.