Seismic strengthening of an existing structure
Founded in 1952, Tawa Baptist Church has been a long standing staple in the surrounding community. Sitting on a seismically active zone, the structure required retrofitting to increase resiliency. The engineer worked with the Tectonus team to find a simple, cost-efficient and easily implementable solution taking into consideration reducing disruption to the building use. The Tectonus tension only braces were fully installed in days with minimum labour requirements and disruption to daily functions.
The single storey building is a steel portal frame structure with masonry infills. In this project, the Tectonus tension-only brace units are rated for 110kN forces with stainless steel rods giving a very high quality finish. As the simplest retrofit solution with significant cost-savings, installing braces added damping to the system while enabling the structure to develop about 1% drift. The presence of 3 pins in each brace prevents the occurrence of buckling when the direction of the movement shortens the brace.
Tectonus units can be fitted with mechanical or digital gauges to show the capacity used during seismic events. In Tawa Church, mechanical gauges were installed and will give a visual indication of the unit capacity used.