Development of a Wireless Sensor to Detect Cracks in Welded Steel Connections

The objective of this thesis is to develop a prototype wireless sensor to detect cracks in welded steel moment resisting connections. These sensors are intended to be installed during construction after the connection has been welded. The sensor comprises two parts: a RF transmitter and a switch. Switches have been developed to monitor the formation of a crack at a single point, or distributed along the length of a weld. An electrical circuit model of the prototype sensor was also developed that provided an excellent representation of the measured characteristic frequency.