Numerical analysis of building damage caused by the exposure of a terrain threshold as a result of underground mining-induced subsidence

Underground mining exploitation causes deformations on the ground surface as a result of the filling of the resulting voids. In certain situations, apart from mild continuous deformations, discontinuous deformations may occur in the form of, e.g., steps in the ground. Unexpectedly occurring discontinuous deformations cause significant damage to buildings protected against the influence of continuous deformations, but do not lead to their complete destruction. For this reason, the aim of this paper is to present a numerical analysis of such an impact case, which, on the one hand, is sufficiently accurate and reflects the behaviour of the real structure, and on the other hand, it will be a guide for experts who will aim to determine the safety of similar structures. In the presented case, the multiple longwall mining of coal ended in the same place resulting in the formation of a step in the ground about 15 cm high under a residential building. Not protected building against such deformations, suffered significant damage. The numerical analysis of the residential building was carried out with the advanced ATENA software package. In order to accurately represent the building and the impacts, the structure and the surrounding ground were modelled. The structure of building and the ground were modelled with tetrahedron- and hexahedral-shaped volumetric elements. On the contact surface of the structure elements and the ground, flat contact elements were used. The loads on the structure were introduced in the form of displacements caused by the appearance of a terrain threshold. The results of numerical calculations are presented in the form of color stress maps. The obtained calculation results are very close to the actual damages, which confirms the correctness of the analysis.