Analysis of removal method of a 19^th church‘s deflection

Silesian University of Technology, Faculty of Civil Engineering, 44-100 Gliwice, ul. Akademicka 5, Poland

^* Corresponding author: krzysztof.gromysz@polsl.pl

Abstract

A historic mid-19^th C. church building is located on the area affected by the impact of underground coal mining. In the past, the building was secured many times against an adverse effect of the mining area deformation by providing massive reinforced-concrete reinforcements. As uneven depressions have emerged, caused by underground coal mining, the structure has become vertically deflected by 39 mm/m in the eastern direction. With the building length of 51 m, the corners have been vertically displaced in relation to each other by 1.99 m. The existing deflection impedes the structure‘s usage, decreases its value and threatens the stability of its furnishings. The deflection should therefore be removed. Due to the building‘s historic character and the presence of massive reinforcements installed already during its operation, three scenarios of deflection rectification were assessed. After the assessment, a scenario was chosen where the building is detached with the use of hydraulic jacks in the floor level, and then straightened by uneven raising. The lifting height of the corners is up to 1.99 m. The article presents the results of the building model calculations and the reinforcements proposed for the time of straightening. It was assumed that the structure, with the total weight of 810,000 tonnes, will be straightened by means of 178 jacks. The outlined procedure will restore the building‘s architectural assets and value and will allow the church goers to use the church comfortably.