[GSBN] Advise Large strawbale structures

[Andy Horn]

Hi 
I have been approached to offer advise to an engineer wanting to build a
most sizable wine cellar with straw bale.

I was wondering of those of you out there who have been involved in the
building of large SB structures, whether there was any specific advise you
could offer or know where to research more detail of the best was to handle
really large structures.

The engineer and his farmer brother have unfortunately already built a set
of standard warehouse steel portal frames without consideration for how a
straw bale structure may work with it. The thing is 52 meters (170 foot)
wide at the gables (with 2 gables next to each other with a valley gutter in
the middle) and 39 meters (130 foot) wide. Steel I sections are set at 6,0
meter (approx 20 foot) centres. 


The side eave walls (39 metres length) are 5 meters high 
The double gable ends (52 meters length) go up to approx 9 - 10 meters
high!!! 

I normally create a ring beam at eave height/every floor .(highest structure
i have done before is a modest 70 sq meter double storey house), so was
thinking ...this would mean using a ring beam/box beam/double horizontal
pole every 3,0 meters high. With vertical timber ladders and timber posts
every 3 bale courses...i.e. at 2,7 m intervals. Then using my normal method
of infilling with dipped bales and pinning and tying them to the timber
frame. The bales go in laid on edge, pre-dipped and partially dried on their
plaster edges and I pin horizontally by cutting a groove in the top of the
bale courses...Not sure if - even though will be using an infill method - we
should try strapping first ring beam at 3,0m height to the foundation and
the higher ring beams to ring beam below it?? Or just fit between and pin
bales to frames. 

Any guidance or pointers to useful sources would be greatly appreciated
Many thanks 
Andy Horn

ECO DESIGN ARCHITECTS
79 Roeland St. Cape Town
www.ecodesignarchitects.co.za