curved steel beam design

huangyhg

curved steel beam design
i am looking for some guidance on designing a steel beam that is "s-curved" in plan view.  the beam is approx. 30' long, the max. offset from a straight line connecting each end is approx. 3'.  this beam supports one edge of a residential floor that is open to below (joists hanging flush to curved beam, railing over curved beam).  the floor trib. is approx. 5' at one end, increasing to 12' near the middle, then back to 5' at the other end.  40 psf ll and 15 psf dl.  i propose a rectangular hss for torsional stability.
i am aware this is complex and am looking for other ways to create what this designer wants.  i would like to know what it would take if he insists on this design.  online research proved fruitless.

could you provide a sketch of the beam in plan view and the applied load?  it need not be anything more than a freehand sketch.

analyze it using risa 3d.
mike mccann
mmc engineering
if you do not have risa 3d (and i do not), analyze it using established structural principals.  if you do not know how to analyze it precisely using established structural principals, try to approximate the answer using the principals you do know.
if, in the end, you do not know how to approximate the answer you are seeking with a reasonable degree of confidence, you must advise your client that you are unable to continue the project using his criteria.  
either he must vary his criteria or you should abandon the project.   to use a piece of software which produces results which you do not have a "feel" for is not professional.  you must decline to continue with the project.

hi keypitsimple,
the steel construction institute (sci) are uk based but they have a publication "design of curved steel" - it may get you started, all you'd have to do is  try to match up code requirements if you're based in the states.
link is:
hope this helps, hm
  
no more things should be presumed to exist than are absolutely necessary - william of occam
msquared48
i have risa 3d and i was not aware that you can analyze a curved   
dwha:
thanks chip. i have done that before with an arch. i was hoping that there was a way to do it as an actual curved   
feed your coordinates into the program in the xz plane segmentally, the same as an arch, then load the