20m Span Floor I Beam VS Truss Beam
20m Span Floor I Beam VS Truss Beam
(OP)
I am designing a double story amphitheater and clear span of this structure is 20m ,so i am stuck in floor beam design , either it should be a simple I beam(Standard Sections) or i should go with hot rolled truss beam so any one can suggest for this type of clear span (20m) which option will be better???
Additional Information:
however the floor joist are UB Section @ spacing 1.2m and frame bay spacing is 5.5 m
floor live load is 5KN/m^2.
Floor Beam is supported by the UC column
Additional Information:
however the floor joist are UB Section @ spacing 1.2m and frame bay spacing is 5.5 m
floor live load is 5KN/m^2.
Floor Beam is supported by the UC column






RE: 20m Span Floor I Beam VS Truss Beam
RE: 20m Span Floor I Beam VS Truss Beam
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: 20m Span Floor I Beam VS Truss Beam
after initial design it comes know that UB762-267-197 section is enough for this span (max deflection is coming 50mm DL+LL) so the effect of vibration will be enough for this much deep beam if yes then how we can control the vibration any suggestion??
however truss depth is required 1150mm so my question is that does the vibration effect will be less in trusses as compare to I beam section??
one more option in my mind is that i run the main floor beam in shorter span (5.5m) and floor joist in longer span (20m) but i guess this will be an expensive option as a lots of splice connection involves due to transportation limitations??
RE: 20m Span Floor I Beam VS Truss Beam
RE: 20m Span Floor I Beam VS Truss Beam
RE: 20m Span Floor I Beam VS Truss Beam
You gotta do the math and get a good match between mass, stiffness, and excitation characteristics.
Often stiffness is a big help with vibration. A deep truss will often be stiffer than a shallower beam.
that does sound promising. You'll have more splices but also a lot few pieces and connections overall to erect.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.