Diagnostic work before reconstruction of the Legion Bridge in Prague
After the fall of the bridge "Trojská lávka", which occurred in December 2017, reasons were sought.
At the same time, a number of historical bridges in Prague have also been found to have a number of shortcomings and their status. E.g. only in Prague 6 it is about 35 bridges.
For the static analysis of the load-bearing structure of the bridge, it is necessary to know not only the mechanical and physical properties of the materials from which the bridge is made, but also its deformation. These deformations depend on the direct load (eg transport), but also on the ambient temperature conditions and the temperature in the actual construction of the bridge.
Temperature information is therefore an integral part of bridge behavior. Both bridges, on which we conduct on-line measurements, are vault constructions, where the temperature course can hardly be simulated by numerical modeling.
That's why we installed these thermometers into the inner parts of the structure. The detected temperature cycles in the annual cycle with accompanying diagnostics allow to assess the real reliability of the structure.
Czech Technical University in Prague
doc. Ing. Petr Bouska, CSc.