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Assalam o alaikum, Dear seniors, Recently i had two design a concealed beam for a case where, A slab of Lounge of dimensions 18 ft x 28 ft is to be designed. The slab is resting on walls o all 4 sides. I broke the span of slab in between and converted it into two panels of 14 ft x18 ft with a beam spaning in 18 ft direction. Slab is of 5 inch thickness and 4 inch thickness finishing. So Total debth of concealed beam i can provide is 9 inch ( 5 inch + 4 inch). Total factored load that comes out to be acting at slab area is nearly 0.22 ksf. I designed this concealed beam with dimensions 24 in width and 9 inch depth. The steel i provided is 10 # 8 US bars at bottom and 6 # 8 US bars at top of beam through out. The design philosofy i followed is that i designed for moment wl2/8 for 9 inch depth and steel required came out 8 # 8 bars. a secion of 24 x 9 in2 can take just 4 #8 bars as singly reinforced section ( i.e. p.max). I had to provided 8 # 8 bars so I provided 10 # 8 bars at bottom and 6 # 8 bars at top ( to balance extra steel provided in bottom so that compressive strength of section equally get increased as tensile strength is increased in excess of rho max) and designed ad doubly reinforced beam. The stirups i provided is #4 @ 6" c/c 2 legged...... Can any one of you confirm me this design? Thanx.