Structural Detailing of Reinforcement for Economy - Simplified Design of Reinforced Concrete Buildings - page 243

lap length

d b

s = (s 1 - d b )

s 1

d b

s = (s 1 - d b )

s 1

(a) Wall and slab reinforcement

Spliced bars

s

Spliced bars

s

s

s

(b) Column with offset corner bars (b) Beam bar splices

Figure 8-2 Effective Clear Spacing of Spliced Bars

apply for all concrete strengths greater than or equal to 3000 psi. For Grade 60 bars, the minimum lap splice
length is 30 d b but not less than 12 in. When bars of different size are lap spliced, the splice length shall be the
larger of 1) development length of larger bar, or 2) splice length of smaller bar (ACI 12.16.2). For columns, the
lap splice lengths may be reduced by a factor of 0.83 when the splice is enclosed throughout its length by ties
specified in ACI 12.17.2.4. The 12 in. minimum lap length also applies.

Table 8-4 Minimum Compression Lap
Splice Lengths for Grade 60 Bars*

Bar
size

Minimum lap length
(in.)

# 3 12

# 4 15

# 5 19

# 6 23

# 7 26

# 8 30

# 9 34

#10 38

#11 42

*

› ≥ 3000 psi