Influence of Foundation Settlement on the Behaviour of Strasbourg Cathedral, France

The Strasbourg Cathedral is actually built on the foundations of a pre-existing church. Settlement is responsible for most of the problems that may be observed in the cathedral. Certain parts of the cathedral, for example, have been built on a layer of gravel deemed incompressible, whereas other parts sit on a bed of silty soil, whereby compressibility is dependent on the groundwater level, a condition that may lead over time to settlement. This set of soil and foundation-related characteristics, in conjunction with a change in the groundwater level, serve to explain the differential rates of settlement observed. In order to assess the condition of the central part of the cathedral and to evaluate the support reactions under settlement, a computation was carried out with the help of a finite element model.