Radome tower structure monitoring, Arctic Canada
Cleland Jardine Engineering Ltd. (CJEL) engaged the services of SHM Canada for monitoring of the Radome tower structure in northern Labrador.
Completed: March 2014
The North Early Warning System comprises a series of radar stations located in the Canadian Arctic Region. Each radar antenna is supported on a structural steel tower and enclosed within a geodesic dome. Typically, these radar towers are situated on high-altitude plateaus and are subjected to unusual environmental and operating conditions – such as large temperature changes (daily and seasonal), ice accretions and high winds, as well as significant eccentric loads oscillating several times a minute. Some of the towers were experiencing cracking of the support structure, as well premature wear of operational components.
An engineering study was commissioned by the owner/operator to evaluate the response of each structure to real-life conditions at three such radar sites. The scope of study included visual inspections, finite element modelling, and validation of the model through measurement of strain, wind, and temperature using an automated Structural Health Monitoring (SHM) system at each site.
SHM Canada was retained by the prime consultant, CJEL, to design, install and operate Structural Health Monitoring systems on the support frames and provide monitoring data for five months. The monitoring data was used to validate the finite element model created by CJEL as part of their study. Various components of the system were customized to enable it to withstand extreme weather conditions and the strong influence of the electromagnetic field that typically surrounds high-energy radar equipment. Data transmission was effected through satellite communication. Data was acquired, reviewed for quality assurance, and forwarded to CJEL on a daily basis, over a five-month period.