Abstract
Weirs are civil engineering structures designed to dam up the stream of water. They are often very old structures subject to preservation care. In order to maintain the level of ground water, it is essential to keep them in good repair. Therefore, weirs require monitoring of their technical condition and geometry.
This article contains an elaboration of the results of measurements of the geometry of a steel cylinder which is a major component of the historical weir Czersko Polskie in Bydgoszcz. The spatial layout and the geometry of the cylinder were determined on the basis of results obtained from measurements referenced to selected points located on its surface, downstream of the dam. The availability of the cylinder surface for the measurements was limited to the visible part, downstream of the structure. Nevertheless, using the adopted calculation procedure it was possible to determine the position of the cylinder axis as well as the twisting and deformation of the cylinder surface.