Phase 2 - Bridge Scour

Background: The objective of the research was to develop a production ready float-out device bridge scour monitoring system. Initially, float-out devices are buried around a bridge abutment at specific locations and depths. After a scour event, a float-out device is released and wirelessly communicates with a receiver, located near the bridge. The receiver produces a visual indication to an inspector in the vicinity of the bridge that a float-out device has been released at the specified location and depth.

Findings: After reviewing the Phase 1 prototype, multiple adjustments were required to the float-out device and radio frequency receiver. The float-out device has been modified to comply with durability and operational requirements. The communication frequency and transmission power have been changed to operate within FCC regulation.

Results: An RF transmission distance test, a capsule pressure test and capsule drop test were performed in the laboratory to ensure that the float-out device can withstand a wide range of environmental conditions. The power reset circuitry developed in Phase 2 was tested to ensure the float-out device can remain active for a period of 20 years. During two different river tests, a simulated scour event verified the operation of the scour monitoring system.

Recommendations: Based on the testing performed in Phase 2, the float-out device bridge scour monitoring system can be deployed and remain operational for a period of 20 years. The installation would provide a test case for the implementation of a state wide scour monitoring system.