Minimum clear spacing between the contact lap splice and adjacent splices or bars is controlled automatically according to 25.2.1.

Tension lap splice length lst for deformed bars and deformed wires in tension is controlled with Table 25.5.2.1.

Compression lap splice length lsc is controlled automatically according to 25.5.5.


Symbols

As = area of nonprestressed longitudinal tension reinforcement, in.2
ld = development length in tension of deformed bar, deformed wire, plain and deformed welded wire reinforcement, or pretensioned strand, in.
ldc = development length in compression of deformed bars and deformed wire, in.
lsc = compression lap splice length, in.
lst = tension lap splice length, in.
Ktr = transverse reinforcement index, in.
db = nominal diameter of bar, wire, or prestressing strand, in
f'c = specified comprehensive strength of concrete, psi
fy = specified yield strength of nonprestressed reinforcement, psi


25.5.1 General

Lap splices couldn’t done for rebars larger than No. 11, according to 25.5.1.1. Minimum clear spacing between the contact lap splice and adjacent splices or bars is controlled according to 25.2.1.Minimum Spacing of Reinforcement

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. for noncontact splices according to 25.5.1.3.

Transverse reinforcement is provided such that Ktr is not be smaller than 0.5db, for bars with fy≥80000 psi, according to 25.5.1.5.

25.5.2 Lap splice lengths of deformed bars and deformed wires in tension

Tension lap splice length lst for deformed bars and deformed wires in tension is controlled with Table 25.5.2.1.

25.5.5 Lap splice lengths of deformed bars in compression

Compression lap splice length lsc of No. 11 or smaller deformed bars in compression is calculated according to the rules below:

(a) For fy≤60000 psi : lsc is the longer of 0.0005fydb and 12 in.
(b) For 60000 psi < fy ≤ 80000 psi: lsc is the longer of (0.0009fy – 24)db and 12 in.
(c) For fy > 80000 psi, lsc is the longer of (0.0009fy – 24)db and lst calculated in accordance with 25.5.2.1.
For f'c < 3000 psi, the length of lap is automatically increased by one-third.

Compression lap splices is not used for bars larger than No. 11.

Compression lap splices of No. 14 or No. 18 bars to No. 11 or smaller bars is permitted. Where bars of different size are lap spliced in compression, lsc is the longer of ldc of larger bar calculated in accordance with 25.4.9.1 and lsc of smaller bar calculated in accordance with 25.5.5.1 as appopriate.