In September 2014, a Resensys structural health monitoring system was deployed on the West and East Bound bridges on I-70 bridge over Patapsco River. The solution consists of several strain gauge SenSpots for monitoring the amount of stress on the deck, girders, and beams, tilt SenSpots to measure the deflection of the piers and rotation of the bridge rocker bearings to temperature change. Resensys wireless SenSpot sensors allows continuous monitoring and measurement of the bridge deck and superstructure thermal expansions and contractions and response of bridge rocker bearings, girders, and piers to thermal expansion. Using this system, damages in the form of fatigue cracks in steel cracks or bridge piers and abutments can be prevented if the accumulated stress (due to malfunctioning bearings) is closely monitored. Thanks to our engineers who have done a great job in installation of over 40 SenSpots. We will keep our big eye on this bridge for a while. Non-responsive bearings had cause damage to piers and steel girders of the bridge, which led to its closure in June 2014.
Tilt SenSpots can measure the rotation of the bearings to verify the correct operation of these members in accommodating thermal movement of the deck.
In the event that some bearings are locked an excessive amount of tilt can be seen on the piers measured through tilt SenSpots. In other words, tilt SenSpots measure the deflection of the piers.
SenSpot installation is done is less than a minute.
The strain gauge SenSpots show if the amount of stress on the deck is in the acceptable range.