Multi-scale hybrid sensor nodes for acceleration-impedance monitoring for steel structural connections

This paper presents hybrid structural health monitoring of steel girder connections using wireless acceleration and impedance sensor nodes based on Imote2-platform. To achieve the research objective, the feasibility of the sensor nodes is examined about its performance for vibration-based global monitoring and impedance-based local monitoring in the structural systems as the following approaches. First, a damage monitoring scheme is described in parallel with global vibration-based methods and local impedance-based methods. Second, multi-scale sensor nodes that enable combined acceleration-impedance monitoring are described on the design of hardware components and embedded software to operate. Third, the performances of the multi-scale sensor nodes are experimentally evaluated from damage monitoring in a lab-scaled steel girder with bolted connection joints.