Concrete slab-on-grade construction and contraction joints incorporate two distinct methods for load transfer and crack control. The first assembly utilizes a continuous keyway formed at mid-depth of the slab with a depth of T/3 and width of T/6 minimum, featuring 1/8-inch radius tooled edges and two inches of clear cover at each side. Reinforcement is interrupted at the joint, and sealant requirements are coordinated with architectural documents. The second assembly incorporates a doweled construction joint utilizing a diamond plate dowel system spaced at 18 to 20 inches on center depending on slab thickness, with a bond breaker applied to the slab edge and reinforcing steel interrupted across the joint interface.
TOOLED EDGES (1/8" RADIUS) CONTINUOUS KEYWAY AT MID-DEPTH OF SLAB SEE ARCHITECTURAL DOCUMENTS FOR SEALANT REQUIREMENTS T T/6 MIN T/3 REINFORCEMENT TO BE INTERRUPTED AT JOINT TOOLED EDGES EQ EQ APPLY BOND BREAKER TO SLAB EDGE DIAMOND PLATE DOWEL SYSTEM: 1/4" @ 18" OC FOR T ≤6" 3/8" @ 18" OC FOR 6" < T ≤8" 3/4" @ 20" OC FOR T > 8" SIDE OF CONSTRUCTION JOINT 2" CLEAR COVER AT EACH B CONSTRUCTION JOINT / CONTRACTION JOINT D DOWELED CONSTRUCTION JOINT (WHERE INDICATED ON PLAN)
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