Rectangular or round openings up to six feet in maximum dimension within a slab on grade are reinforced with two number four reinforcing bars placed diagonally in each corner at the slab midheight. These diagonal hairpins extend two feet past the opening corners with a three inch clearance from the edge. Openings smaller than two feet eliminate the need for these bars and keyed joints. The top of slab elevation is established per plan.
RECTANGULAR OR ROUND OPENING (2) #4 IN EA CORNER AT MIDHEIGHT ON SLAB PLAN NOTE: ELIMINATE BARS AND KEYED JOINT IF OPENING IS LESS THAN 2'-0". 6'-0" MAX 6'-0" MAX TYP 2' - 0" TYP 2' - 0" 3" TYP 2" TOP OF SLAB PER PLAN
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