In addition, these detailing requirements have been frequently revised in recent years. The required length of lap or development is determined according to the design procedure used (allowable stress design or strength design). Reinforcing bars may be spliced by lapping the reinforcement, by proprietary mechanical splices or by welding. The development of the reinforcing bars relies on mechanical interlock of the bar deformations, hook, and/or anchor along with sufficient masonry cover to prevent splitting of the masonry. Reinforcement can be developed by embedment length, hook, or mechanical anchoring device. Splicing of reinforcement serves a similar purpose: to adequately transfer stresses from one reinforcing bar to another. Minimum development lengths are necessary to adequately transfer stresses between reinforcement and the grout or mortar in which it is embedded. 7), covers these requirements based on the 20 editions of the IBC. TEK 12-6, Splices, Development and Standard Hooks for Concrete Masonry (ref. In addition, prestressing steel is discussed in Post-Tensioned Concrete Masonry Wall Construction, TEK 3-14 (ref. 5) includes basic material requirements, corrosion protection and placement tolerances for reinforcement used in concrete masonry construction.
#Aci class b lap splice code
Masonry design in these codes is primarily based on Building Code Requirements for Masonry Structures (MSJC) (refs. This TEK presents these requirements, based on the provisions of both the 20 editions of the International Building Code (IBC) (refs. Where bars of different sizes are lap spliced in compression, l sc is the longer l dc of the larger bar calculated in accordance with 25.4.9.1, and l sc of the smaller bar is calculated in accordance with 25.5.5.1 as appropriate.Building codes include requirements for minimum reinforcement development lengths and splice lengths, as well as requirements for standard hooks, to ensure the adequate transfer of stresses between the reinforcement and the masonry. 80000 psi, l sc is the longer of (0.0009f y – 24)d b and l stcalculated in accordance with 25.5.2.1.įor f ' c < 3000 psi, the length of the lap is automatically increased by one-third.Ĭompression lap splices are not used for bars larger than No. Maximum percent of A s spliced within required lap length Tension lap splice length l st for deformed bars and deformed wires in tension is controlled with Table 25.5.2.1.Ī s,provided/A s,required over length of splice Lap splice lengths of deformed bars and deformed wires in tension Transverse reinforcement is provided such that K tr is not smaller than 0.5d b, for bars with fy≥80000 psi, according to 25.5.1.5. for noncontact splices, according to 25.5.1.3. The transverse center-to-center spacing of spliced bars does not exceed the lesser of 1/5 the required lap splice length and 6 in. Minimum Spacing of Reinforcement per ACI 318-19 with ideCAD
Minimum clear spacing between the contact lap splice and adjacent splices or bars is controlled according to 25.2.1. Lap splices couldn’t be done for rebars larger than No. K tr = transverse reinforcement index, in.ĭ b = nominal diameter of bar, wire, or prestressing strand, inį' c = specified comprehensive strength of concrete, psiį y = specified yield strength of nonprestressed reinforcement, psi L sc = compression lap splice length, in.
L dc = development length in compression of deformed bars and deformed wire, in. L d = development length in tension of deformed bar, deformed wire, plain and deformed welded wire reinforcement, or pretensioned strand, in. Compression lap splice length l sc is controlled automatically according to 25.5.5.Ī s = area of nonprestressed longitudinal tension reinforcement, in.2
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