Pre-fabricated Stress Laminated Timber Bridge. Glen Alton Forest, Clarence River Valley

The TrailGate bridge is a pre-fabricated Stress Laminated Timber (SLT) bridge with two six-meter spans. It is designed for “lightly trafficked rural” applications such as farm road infrastructure and secondary public road bridges. The design choices are aimed at preserving the simplicity of assembly and use of standard farm machinery (farm tractor, fence post driver and digger) in the construction and assembly phase. Individual components of the bridge are sized so that they can easily be handled by two persons. The design choices allow the bridge to be manufactured using trade skills and commercially available components, with no specialised equipment for the manufacture of individual component parts. Design choices are guided by simplicity and oriented towards “low tech” solutions making the bridge design and construction accessible to small and medium size contractors with construction capabilities and skills available throughout New Zealand.