Rectangular Concrete Beam Section Analysis Crack Control per. ACI 318-95 Codes

Civil Engineering Design Data | Beam Deflection Equation and Calculators

Crack Control - Distribution of Flexural Reinforcing
Per ACI 318-05 and ACI 318-95 Codes
Input Data:
Beam or Slab Section?
Exterior or Interior Exposure?
Reinforcing Yield Strength, fy = ksi
Concrete Comp. Strength, f 'c = ksi
Depth to Tension Reinforcing, d = in.
Tension Reinforcing, As = in.^2
Tension Reinf. Bar Spacing, s = in.
Clear Cover to Tension Reinf., Cc = in.
Working Stress Moment, Ma = ft-kips
Per ACI 318-05 Code:
Es =
The Modulus of Elasticity for Steel, 'Es', is assumed = 29,000 ksi
Ec =
The Modulus of Elasticity for Concrete, 'Ec', is calculated as follows:
Ec = 57*(f'c*1000)^(1/2) ksi
Note: "normal" weight concrete is assumed.
n =
The Modular Ratio, 'n', is calculated as follows:
n = Es/Ec
n = Es/Ec
fs =
The working stress tension in the reinforcing, 'fs', is calculated as follows:
fs = 12*Ma/(n*As*d*(1-((2*As/b*d)+(n*As/(b*d))^2)^(1/2)-n*As/(b*d))/3))
fs(used) =
The actual value of 'fs' used in the calculation of the required spacing of flexural tension reinforcing shall be the lesser of the calculated value of 'fs' based on the applied moment and 2/3*fy.
ksi  (lesser of 'fs' and 2/3*fy)
s(max) =
The center-to-center spacing, 's', of the flexural tension reinforcing shall not exceed the following:
s(max) = 15*(40000/(fs*1000))-2.5*Cc
but not greater than 12*(40/fs).
Per ACI 318-95 Code:
dc =
The concrete cover, 'dc', is the distance from the tension face of the beam/section to the centerline of the tension reinforcing and is calculated as follows:
dc = h-d
z =
The factor limiting the distribution of flexural reinforcement, 'z', is calculated as follows:
z = fs*(dc*2*dc*b/Nb)^(1/3)
z(allow) =
The allowable factor limiting the distribution of flexural reinforcement, 'z(allow)', shall not exceed the following values:
Interior Exposure: Exterior Exposure:
Beams z = 175 z = 145
One-way slabs z = 156 z =129
Contribute Article
Spider Optimizer

© Copyright 2000 - 2017, by Engineers Edge, LLC
All rights reserved
Disclaimer | Feedback | Advertising | Contact

User Reviews/Comments:

There are currently no comments available.

Add a Comment (you must be logged in to post comment Register):
Email: (Optional)