One-Way Slab Design Strip

M_{u} = \frac{w _{u} ℓ _{n}^{2}}{8} (simple) t_{m i n} = \frac{ℓ}{20} (SS, ACI)

One-way action: main steel perpendicular to the long supports. Design a 12-in-wide strip. Continuous ACI moment coefficients (e.g. wu ln²/11 interior positive) when qualifying spans. Temperature steel in the other direction.

$w_{u}$: Factored uniform load on the strip
$ℓ_{n}$: Clear span

Step-by-step solved example

Simple 12-in strip, wu=0.20 kip/ft, ln=12 ft. Mu?

Design strip 12 in wide; loads from slab tributary.

1. Simple Mu
Mu= w ℓ²/8 = 0.20×144/8=3.60 kip·ft / ft width.

Answer: 3.60 kip·ft per foot of slab

10 practice questions

0/10 correct

1.One-way vs two-way: ACI uses

2.Main flexural steel runs

3.tmin for simple solid one-way (ACI, fy=60) is about

4.Temperature/shrinkage steel is

5.A 12-in strip wu is

6.Interior positive coefficient wu ln²/16 (or /11 depending on condition) is

7.Clear span ln is

8.Cover for interior slab bars is typically

9.Check shear in a one-way slab as

10.Distribution bars (if used) help