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Adaptations of road infrastructure must often be performed without interruption of traffic. Vibrations induced by ongoing traffic propagate to structural elements under construction and may affect the concrete hardening process and thus negatively influence quality of the final structure. This paper examines major influencing factors that contribute to large bridge vibration velocities during widening of bridge deck with ongoing traffic. The vibrations are evaluated in light of the considered limit for fresh concrete in hardening process. The analysis presents a case study of a reinforced-concrete bridge under traffic excitation. Vehicle velocity, type, mass, as well as road profile characteristic were varied in the simulation and bridge vibration amplitudes were calculated using full vehicle-structure interaction. The simulation results provide a basis for meaningful discussion on necessary traffic restrictions or other measures to avoid quality impairment in construction.

Trains passing through railway tunnels cause pressure and suction waves which affect the vehicle, tunnel equipment, and passenger comfort. In the Alps, several very long single-track, twin-tube tunnels either have been opened recently or are under construction. Pressurized cross passage tubes spaced every 333 to 500 meters interconnect the main tunnel tubes and are sealed with air-tight doors which must sustain high pressure loads. The impact of various configurations of the shallow cavity between the main tube and the cross passage and the pressure loads generated on installations in different configurations of high-speed tunnels are analysed by using Computational Fluid Dynamics (CFD) analysis and experimental validations at the Tunnel Simulation Facility Göttingen (TSG) in model scale experiments (1:25). The effects on internal tunnel installations (e.g., emergency exit doors) were investigated in connection with their structural dynamics using FEA. The life span was evaluated and compared with the cumulative damage method after Palmgren- Miner.