Canopy Tension

[ataman]

Hi

I'm working with an architect who wants to design a canopy over a pool deck to provide shade. The canopy which will be made out of a canvas type material will span about 13m between steel poles which will act a support. The canopy will have a slight slope to allow water to sheet off but we would need to apply a tension to the system so that we don't get any ponding. Herein lies by question. How do I go about calculating the amount of tension that is required so that I can design the columns and bracing.

Thanks

 

[civilperson]

Use caternary formula.

 

[msquared48]

I would also talk to the manufacturer of the canopy material. He may have specs, guidelines, and tensioon limits for his product. If there is a max tension, that would describe the catenary.

Mike McCann
McCann Engineering

 

[csd72]

ataman,

these things are prone to stability problems when snow loaded as the ponding can be a big issue. Make sure there is a good slope, not just the minimum for ponding.

Roarks has some good catenary formulii.

ASCE has a book on tension structures but it more about the details rather than any specific advice on calculations.

csd

 

[hokie66]

May not be the case where you are, but in Australia the design of tension membrane systems is normally done by specialist engineers who work for or provide services to the tension structure contractors. The overall project structural engineer is then provided with forces for design of the supporting structure or footings.