A length of reinforcement is left protruding up from the top of every grout pour, to lap with the reinforcement in the next grout pour. Lap splices are used to ensure reinforcement continuity up the height of the wall. Mortar protruding more than ½” into the grouted cell must be removed before grouting ( Building Code Requirements and Specification for Masonry Structures Spec. Small amounts of mortar and debris are acceptable so long as grout bond is not severely inhibited. Special care needs to be taken when building reinforced masonry walls to prevent excessive amounts of debris, mortar droppings, etc., from falling into the reinforced cell. These units have one or both end webs removed, and can be placed around vertical reinforcement projecting up from the foundation or the previous grout pour. The practice of stabbing bars into freshly placed grout is not permitted as it does not permit the inspector to verify proper reinforcement placement.Īnother option is to use open-end “A” or “H” block units. The Building Code Requirements and Specification for Masonry Structures requires reinforcement to be in place prior to grouting (See Building Code Requirements and Specification for Masonry Structures Section 3.2 E). It is good construction practice to have vertical reinforcement in place before grouting. Vertical reinforcement is typically placed by dropping the bar into empty cells after the wall is built. Splices, Development and Standard Hooks for Concrete Masonry Walls.For 8-inch masonry units, the cell area is approximately 32 square inches, into which a maximum of 1.3 square inches of reinforcement may be placed. The total reinforcement area placed in a cell may not exceed 4 percent of the cell area (8% at lap splice locations). When masonry is designed using the Strength Design provisions ( Building Code Requirements and Specification for Masonry Structures Chapter 3) the maximum bar size is limited to the lesser of #9 bars, 1/8 times the nominal wall thickness, or ¼ of the clear dimension of the cell, course, or collar joint being reinforced. The Building Code Requirements and Specification for Masonry Structures reported by the Masonry Standards Joint Committee (MSJC) permits reinforcement sizes up to #11 (1 3/8” diameter) to be used in masonry construction, but it is rare to see bars larger than #8 (1” diameter). Grade 60 reinforcement with a yield strength of 60,000 psi is most common in some markets Grade 40 (yield strength of 40,000 psi) may also be available. Steel Reinforcement for Concrete Masonryĭeformed reinforcing bars (rebar) should conform to ASTM A 615.Reinforced Brick Masonry - Materials and Construction.Reinforced Brick Masonry - Introduction.Masonry columns and pilasters are also reinforced vertically to increase resistance to axial loads. Vertical reinforcement is used in masonry walls to resist tensile stresses that may arise from flexural and shear loads.
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