Timber portal frame

Since i am concentrating on LVL and concrete in my project i thought it would be interesting to look at another project, besides the Brambuk Living Cultural and Information Centre, that the engineering consultants PJ Ytrrup and Associates have worked on.

This one is a store building in Mount Gambier, South Australia.

As you can see from these pictures the rafters and columns are LVL sections with nailed plywood gussets that provide for full moment connections. The purlins, girts and knee bracing are also all made from LVL. This particular portal frame has a span of up to 32m.

When it came to assembling the portal frame progressive crane lifts, a technique developed by Yttrup, was used to construct the crusher, dryer and gluing buildings. The building was fabricated with the column hinged to the rafters with all of the purlins and girts installed. Upon crane lifting the rafters, the columns rotated into position. The press and finishing building was constructed by standing the columns up unsupported on their rigid base connection. The rafters were then lifted into place as half span pairs with purlins attached.