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Temporary supports, consisting of a stack of wooden elements and a hydraulic jack, are used in the process of removing deflections in buildings with one to three aboveground floors in mining areas. During uneven raising, the supports are loaded monotonically, unloaded and loaded cyclically. Laboratory tests were designed for the supports. For the investigated range of loads of 0 to 400 kN, under a growing load, a linear relationship exists between a load and the change in the stack length, which signifies that the deformations of wooden elements and displacements related to their mutual interactions increase proportionally. A seemingly higher stack stiffness is seen at the beginning of the unloading process and for cyclical loads, meaning that in this phase of loading, the material deformation of the wooden elements and the jack is responsible for changing the jack length in this load phase, with a negligible presence of mutual displacements of wooden elements. The support, after being unloaded, returns to the initial position and its permanent deformations are not observed. The stiffness of a temporary support decreases as the height of the stack of wooden elements increases.

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In the article a case study of consequences of underground mining exploitation of hard coal deposit on terrain surface and in a residential building has been presented. It was realized an exploitation of two hard coal seams (in three layers) in Poland, in the Upper Silesian Coal Basin, in 2013 – 2019. Operation was conducted at relatively small depth and by use of five longwalls with significant height and large decline. There were observed exploitation influences of fifth longwall on terrain surface and in the building by use of geodetic surveys. Measurements were carried out on the ground and wall points located in two perpendicular directions. Heights differences and distances between next points before and after the end of exploitation of last longwall have been measured. There the inclinations changes of particular sections have been determined. Analysis of surveys results shown that processes of the terrain and buildings deformations take place differently and terrain inclinations and building deviations have other values. Moreover, next to the building four discontinuous linear deformations of terrain surface (one in front of the building, one under the building, two behind the building) have been occurred. The ground steps location was detected by use of profile leveling of road located on the east of the building. A ground step with height of 15 cm under the building caused its crack. Example of the building with a partial basement proved that a consolidation type of building in the ground has a significant influence on values of its deviations.

The subject of the article is an analysis of the stabilisation method of the western gable walls of a barrack with the inventory number B-123, situated at the section BI of the former German Nazi concentration and extermination camp Auschwitz II-Birkenau. The barracks of the former Birkenau have a documentary and historical value and are subject to protective conservation. A barrack with inv. no. B-123 had been erected in the last months of 1941 as a residential barrack, then it was used as a hospital facility. The barrack walls are characterised by low stiffness, because with the building’s plan of 36.17 m  11.39 m, the walls are only 0.12 m thick. Gable walls have been greatly deformed, as a result they have detached from longitudinal walls and their deflection is up to 120 mm. The construction of the walls is at risk, because a bad-quality wall is loaded with horizontal and vertical forces transmitted from the roof, on the eccentricity reaching 120 mm. Deformations are progressing as a consequence of such forces and the walls must be stabilised. In case of the western wall, it was decided to stop its further deformation and to increase the local carrying capacity by stabilising with steel elements connected with ties anchored in the ground. Given the historical value of the plasters with paint coats layers covering the wall, it was decided not to remove the wall deformation mechanically. For the eastern wall, which is not covered with plaster and was partly reconstructed after the war, the removal of its deflection by rectification was designed.

The construction of the German Nazi concentration and extermination camp Auschwitz II - Birkenau started at the end of 1941. A barrack with the current inventory no. B-123, situated at the section BI, was then erected. The barrack has a documentary and historical value. The barrack walls are characterised by the low stiffness, because with the building’s plan of 36.17 m × 11.39 m, the walls are only 0.12 m thick. All the outer walls have been substantially deformed or vertically deflected. Up to 100 mm wide gaps have formed between the deformed and deflected external walls and contiguous walls as a result. The stability of the walls was at risk, because a bad-quality wall was loaded with horizontal and vertical forces transmitted from the roof on the eccentricity reaching 100 mm. Deformations were progressing over time as a consequence of such forces. Individual rectification procedures were designed and implemented for each wall as part of the comprehensive conservatory and building works, the purpose of which was to ensure the stability. This article presents a procedure of rectification the eastern gable wall and the outer, longitudinal northern wall. The deformation of the eastern gable wall was removed by changing its static scheme, by inserting hinge regions into the wall along the line of selected bed joints. Separate wall patches, which could rotate relative to each other, were created as a result of the forces acting perpendicular to the wall surface. By causing the mutual rotation of such patches, the eastern gable wall reached the desired vertical position. The vertically deflected, longitudinal outer northern wall was rectified by rotating the wall in relation to the wall support edge on the foundations. An analogous procedure was applied to the outer longitudinal southern wall. After the completed rectification, the walls were anchored to the contiguous walls; the places of rotation and anchoring were filled with mortar. A different procedure was adopted for the other deflected walls. The advancing deformations of the western gable wall were stopped by stabilising its position with the steel elements connected with ties anchored in the ground. It was inadmissible to rectify this wall because it is covered with plaster and paint coats with a high historical value.