Concrete filled HSS column to flat plate moment conn.
Concrete filled HSS column to flat plate moment conn.
(OP)
One of my current projects is an irregularly shaped work platform or mezzanine. I have designed other more regularly shaped mezzanines using a steel braced frame and composite deck that worked well. Because of the shape of the current platform and limitations on column / brace locations the one way nature of composite slabs is not going to work well and I'm looking into other structural systems. The client wants concrete for the floor surface. I would like to use concrete filled HSS columns and a reinforced concrete slab with rigid connections to the columns if I can get it to work. If not I could try steel columns to composite beam & slab moment frame. The latter system is common and well documented. I havent had any luck finding any info on filled HSS columns to concrete beam or slab connections though. Any idea's or resources to suggest? Thanks.






RE: Concrete filled HSS column to flat plate moment conn.
RE: Concrete filled HSS column to flat plate moment conn.
RE: Concrete filled HSS column to flat plate moment conn.
RE: Concrete filled HSS column to flat plate moment conn.
RE: Concrete filled HSS column to flat plate moment conn.
Now, composite structures in general are not the better for strong motion or blast. There's always then something hard and strong, the steel, punching its way throug the weaker concrete. I always remember how in the 1st bombing of the basement of WTC the slabs were cleanly spitted off the shearhead by the explosion.
In your context, however and anyway, a weak shear-head may still work. Sometimes even here that we have only less than .04g surface EQ accelerations I have used horizontal connectors to the shearheads to enhance connection. Furthermore the shear-head will help for inversion of moments; AND, since you are required to calculate the structure for the condition of strong motion, ascertain well its degraded stiffness, this might help to comply with an enforced strong column approach.
Also, if seemingly noncomplying, I would look if compliance on fundamentals of engineering is permitted by the code; for, frankly, for a structure like yours, any adscription of such a thing as a "beam" looks as imagination. This is a irregular plate on columns; does the code gives specific procedure to analyze such structure? prohibits it? If not, you may analyze it according to the science of construction, and showing compliance with all those requirements that are clearly still applicable should suffice.
RE: Concrete filled HSS column to flat plate moment conn.
RE: Concrete filled HSS column to flat plate moment conn.