Instruments for bridge control and  monitoring

The instrumentation designed and produced by us, currently used for the control of countless civil works of great importance, both for the technical structural aspects and for the “risk” aspects (dams, bridges, tunnels, large works in general), is of proven quality and reliability. Even if mainly applied on dams it is clear that this is not a limitation of applicability but only of opportunity. Unfortunately, the importance of monitoring becomes evident only after serious disasters; examples are the Vajont dam and the Morandi bridge. 

This last example has meant that bridge monitoring has exploded, both in the construction and management phases; Having some of the fundamental parameters of the structure under control can allow you to obtain valuable information on the state of health of the work and be able to intervene on it to avoid unforgivable disasters. New generation instruments are now available on the market, or presumed to be such, which are proposed (and requested) specifically for the control of bridges, as if a bridge were a completely different structure from other large structures and was not regulated by the same laws and problems given, for example, by the settlements of the ground, by the stability of the shoulders, by the displacements, by the inclinations of the pylons, by the joints, by the loads to be supported, by the concrete with its stresses and deformations and above all by its intrinsic qualities and characteristics (elastic modulus, …), by temperatures, by wind, by rain, by vibrations, etc etc, 

The necessary instrumentation is the same that we use on a dam, on a monument, in a tunnel, on any other large work with obviously some different operational problems (generally, on a bridge, there is no power supply and there is no fixed control house nearby but , nothing special. Settlement is always checked with plate settling gauges, BRS or USBR columns and probes, settling cells, topographic surveys, GPS, collimations, while the stability of the shoulders can be checked with stainless steel or fiberglass bar extensometers, load cells for tie rods and for load on the foundation soil, topographic measurements again. For the horizontal movements and rotations of the pylons, and therefore of the bridge, we still have collimation, pendulums with laser coordinometers, clinometers and/or tiltometers, inclinometric columns, GPS, Total Station for topographic measurements, etc. Strain gauges, both mechanical and vibrating wire, or LVDT or potentiometric, are used for checking joints while for deformations and/or stresses of the concrete (or iron) we offer our CV strain gauge bars. or electrical and tensiometric capsules. Finally, our meteo sensors (barometer, thermometer, hygrometer, anemometer for wind speed and direction, rain gauge, etc.), automatically control the surrounding weather conditions with all the parameters that can externally influence the stability of the structure. 

All these controls can be mechanical or automatic; the various electric sensors mentioned can be connected via cable to local acquisition units or can be connected remotely thanks to wireless measurement and transmission devices, VW-MDB vibrating wire converters (from vibrating wire to RS485 -MDBus), sensor digitizers analogue (Digitizer PZ-8I), Mesh technology nodes, LoRa communication transmitters, or IoT technology. Our SENTINEL software, for data management, equipped with a powerful and tested Data Base, is also able to manage measurements and communicate with the various digitized sensors or with local Acquisition Units (DAC3000 or CUM3000) Dynamic control systems, such as accelerometers and dynamic recorders, allow the control of the vibrational state of the structure and the consequent possibility of analyzing the structural behavior in comparison with the static characteristic data. we remember the GeoSIG products such as accelerometers, seismometers, velocimeters, recorders, etc etc