Bridges feature within lifelines where the sheer volume of traffic without any monitoring solution would cause severe safety problems and significant interference to the free movement of goods, services and people between trading nations. Bridges can feature within road to road traffic solutions within traffic management systems designed to minimise lengthy road transport delays, and longer bridges can feature as essential links between any mainland and its nearby island otherwise separated by sea. Bridges may feature in geographical areas that alone warrant the monitoring of seismic effects caused by natural earth activity, and may feature at localities exposed to higher than average wind speeds. As with tunnels GeoSIG demonstrate the necessary understanding of the technologies required to become a genuine competitor offering a Swiss made solution no matter how daunting the bridge challenge first appears. 

The scope of the Oresund project was to deliver a Cable Stayed Bridge Structural Monitoring System. Oresund is an Impressive highway and railway link consisting of an immersed tunnel, artificial island and a combination bridge requiring observation of the oscillations of cables of the stayed bridge under heavy wind conditions. The bridge system solution monitors the deflections of the bridge under loads generated by the highway and railway traffic. An on-site traffic control centre of the bridge is where excesses of any threshold values are recorded and managed from. 

The system comprises 105 channels and a data acquisition and processing centre, digital RS-485 cable communication with provision for 15 hours autonomy in case of power failure. Temperature/environmental data correlation are made alongside strain gauge measurements. A single CR-4 PC based recording system running programs, SEISLOG data acquisition, CENTRAL remote access, CMS, and static data processing. A telephone line connection to the traffic control centre is provided for data, event and alarm transmission.

 

Solution	Type	Product
22 x Accelerometers	Triaxial Force Balance Accelerometer	AC-53
19 x Strain Sensors	Uniaxial Strain Gage	GSG-XX
14 x Metereological Sensors	Temperature Sensor, Weather Station	METEO-TT METEO-WSDT
1 x Data Acquisition And Processing Centre	Electronic Cabinet computer Software	RACK-1 Computer GeoDAS, CMS