Truss failure - video

[Frank S]

A light weight and one of the strongest roof systems there is would be a space frame structure. The company I was with before retiring build among other things lots of steel structured buildings some of our space frame designs clear spanned 200 ft by 300 ft on 3 sides made up of a labyrinth of small pipes all bolted together no single connection carrying more than another once complete



and to secure glass panels we used stainless steel spiders
the pic also shows how the system connected together

And for the lightest fastest structure to erect the award has to go to K span.
anything under 30 ft wide by 18 ft tall only needs a 3/8" thick by 6 inch wide curved steel rib placed between every 10 feet of roof panels 60 ft by 30 to 35 ft tall buildings needed 3/4" thick by 10 inches added every 30 ft along with the smaller ones. the panels were made on site in a mobile form rolling machine from coils

[SRQSid]

One more thing from the dustbin of history: In 1961 the family lumber business built a modest store/showroom, about 20 X 30 or so. The trusses were built on-site using split rings which connected the sides of overlapping 2 X 4 truss chords and webs. Circular grooves were cut in both members and the ring rested half in each and secured by a center through bolt. The ring was split so it could adjust to the wood's changing size due to seasonal moisture level changes. This was constructed by employees when things were slow and has stood the test of time (55+years) and western Massachusetts snow loads.
This may be an option for modest DIY projects at difficult sites using engineered drawings.
Link: Split Ring Timber Connectors - Split Ring Connectors

[SRQSid]

The last shot looks a larger version of a Quonset Hut. Quick and easy construction made it popular and necessary during WW2. The name comes from their place of manufacture, Quonset Point, RI.

[Frank S]

The last shot looks a larger version of a Quonset Hut. Quick and easy construction made it popular and necessary during WW2. The name comes from their place of manufacture, Quonset Point, RI.

Yes actually just the newer version except instead of taking corrugated sheets and curving them or using High edge rib standing seam heavy galvanized metal the K span is made from stupidly thin gauge metal that comes in 24 ft wide coils a 1000's of ft in length rolled to shape and curved in the same machine right on location
In another division of the company we had a 45 ft high cube container with a roll form machine to make the std commercial siding and roof sheeting on location it made 2 shapes of metal one above the other at the same time or separate When making both the upper an lower sheets simultaneously they were routed through 2 more double open ended containers placed in line with the forming machine in the middle container foam was injected between the sheets in the last container the now sandwich panels were cured and cut to length. Other construction companies mostly imported their sandwich panels from Izopoli in Turkey we Leased the equipment and made our own under license and partnership with Izopoli