This structural detail provides standard reinforcing requirements for penetrations in one-way concrete floor and roof slabs. Large openings exceeding one foot six inches up to four feet in width require two number five top and bottom bars placed above and below the main reinforcement, along with four-foot-long diagonal bars at each layer extending to supports. Small openings under one foot ten inches maximum width utilize scheduled reinforcement with one continuous bar on each side of the opening and three-foot-long diagonal bars. Additional top and bottom reinforcement equal to half of the steel interrupted by the opening is placed at three inches on center each side unless noted otherwise, with added reinforcing extended fully to the supports.
14" 42" LARGE OPENINGS SMALL OPENINGS 14" (2) #5 T&B TOP BELOW MAIN REINF, BOT ABOVE MAIN REINF #4x5'-0" DIAG FOR EA LAYER OF MAIN REINF HOOK T&B BARS UNINTERRUPTED MAIN BAR ADD T&B REINF EQ TO HALF OF THAT INTERRUPTED BY OPNG @ 3" OC ES UNO EXTEND ADDED REINF TO SUPTS #4x3'-0" DIAG ADD (1) CONT BAR ES OF OPNG (1) #5 T&B SCHED REINF SPAN SPAN 1'-10" 1'-6" MAX MAX TYP 2' - 0" GREATER THAN 1'-6" (4'-0" MAX)
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