"24/7 Technical Inspections" for Bridges

Every hairline crack or minute change in the fabric of a building structure emits sonic signals. These "stress relaxations" are audible and provide a clear indication of the condition of the underlying material. Besides frost, heat or vibrations, the prevailing, high-frequency ambient sounds can also make it harder to 'clearly hear' a structure from the outside. Now that this technology has been refined, Bilfinger is able to listen in to the sounds emitted by a bridge's supporting structure.

The acoustic emissions analysis used by Bilfinger in monitoring the safety of bridge-bearing structures is helping to make Germany's roads even safer. This service allows any incipient structural deteriorations to be identified promptly and located more precisely. To this end, Bilfinger continuously monitors the structure using sensor technology and intelligent data analysis.

In a pilot project pursued jointly with the local public transport company Hessen Mobil, intelligent acoustic emissions testing (AET) was successfully used for the first time to monitor the load-bearing structures of the Thalaubach viaduct near Fulda. The complex data-analysis process uses high-tech sensors in combination with special software that can track every single event occurring in the structural fabric, even under challenging environmental conditions. Thus, it was possible to keep Autobahn A7 in uninterrupted service throughout the entire critical winter season.

Our costumer promise: this innovation supplements visual inspections and walk-throughs, raising the inspection of bridge structures to a new level.