Project on the preservation of mining history evidence on the original site:
the Henrichenburg boat lift
The Henrichenburg boat lift, inaugurated in 1899, is – in terms of the history of technology – one of the most important hydraulic engineering structures in the region, and is still the largest structure on the Dortmund-Ems Canal. Since 2010 we have been helping the LWL-Industriemuseum to document the stone surfaces in line with heritage protection standards.
The stone surfaces of the trough of the boat lift showed deformation, cracks, exfoliation, biogenic encrustation and moisture damage. Our first task was to record this damage. To do this we worked closely with the stone conservator Franz Moll to develop an image-based pilot project mapping the north side of the stone trough construction. Because of the steel superstructure the image data had to be produced freehand, while climbing on the construction – a laborious procedure. Later it was necessary to rectify the digital image material using our own site survey as base data, i.e., geometrical lens distortions were removed by means of computer-aided image processing. The damage was then digitally plotted in the rectified image documentation using CAD software.
In 2011 our focus was on investigating possible ways to repair the damage found. To begin with, it was important to establish whether the causes for the cracks found in the stone were still present, or whether they had been caused by overloading which was no longer present. Based on knowledge about the development of the cracks, decisions about strengthening or load removal can be made. We therefore installed ten monitors to study the development of the cracks, and recorded the zero position with digital photographs. The monitors are checked at regular intervals to record any possible development of cracks. A restoration plan is being produced on the basis of the mapping of the damage, and the implementation of these measures is planned as part of the current project for subsequent years. The research department for information systems will provide academic support for the restoration work as an exemplary pilot project.
Restaurator Franz Moll
2012 - 2014