In the case of railway facilities, there is particularly important to analyse work constructions under dynamic loads. Excessive railway bridge structure can threaten the movement by creating unacceptable changes in the vertical and horizontal track geometry, by creating excessive strain on rails and vibration of bridge structures. Excessive vibration can lead to instability ballast and unacceptable reduction of forces in contact with the rail wheels. Excessive strain can also have an effect on load utility in a track / bridge system and create conditions causing discomfort to passengers. The control of strain bridge structures should be carried out due to the safety and comfort of passengers. It is important to control movements and accelerations. While the acceleration measurements are relatively simple to implement, the measurements of displacements in automatic and unattended operations cause considerable difficulties.
The practical aim of the project is to develop a monitoring system for bridge constructions, a method for the measurement and evaluation of the dynamic response (hereinafter MODO). For MODO will consist of a measurement methodology, data analysis and inference, and a set of tools (hardware and of software) unit of measurement of response of dynamic operating railway bridge construction. MODO will be designed to monitor structural steel span length greater than 30 m, i.e. construction, in the case where it is not easy to substitute temporary structures for renovation or building a new structure.
As an object, the first railway bridge at the Citadel in Warsaw was selected. These are two old constructions with a span truss equal 5x67,60 + 66.80 + 66.80 m. On the bridge there is a significant amount of traffic - daily 130 passenger trains and 40 freight trains and small traveling speed - up to 40 km/h.
As a second object, an overpass at km 8 26.571 / 26.578 CMK line 4 (in the neighbourhood Huta Zawadzka) was selected. These are two new arc structures with a span length equal to 75.00 m. The facility was put into service at speeds up to 250 km/h.