minimum conc. beam size

huangyhg

minimum conc. beam size
i am designing a trellis structure. it measures 6x24 in plan view. the top beams in the long direction are  supported by columns at 6' o.c. (e.g. 4 typical spans each 6'-0" long.)
this beam will support very light wood trellis on top.
the beam will be cladded with coral rock veneer for a total dimenssion including finish of 12"x8" cross section.
question:
1. can the cross section of the beam be 5"x8.5"?
2. what is the minimum beam size allowed by aci318?
thanks.
provide required concrete cover to longitudinal reinforcing.  provide adequate spacing between bars.  is this a two way concrete frame?
minimum bean size 8x12
but it can be anything smaller by calculations
for cast in place 5" would probably by the minimum width, assume 2 # 4 bars @ 1/2" dia. ea, 2" clear each side and 1 " between the bars (using 3/4 " agg.)
however i would go at least 6" to give a little more room around the bars.
*.5" high is okay, but you may find it more convient to go 7.5 or 9.5 inches. this would allow you to use 2x8's or 2x10's for side forms.
good luck