Concrete Beam Design

Project:

Lafarge Republic Inc Platform

Reference No. :

Version 2.0

I. BEAM DETAILS: BEAM MARK: Beam Width B = Beam Height H = Concrete Clear Cover cc = Size of Flexural Reinforcement db = Size of Stirrup dbs = No. of leg = Reduction factor flexure, ø = Reduction factor shear, ø = REINFORCED CONCRETE DESIGN PROPER:

Subject:

B-1

Beam Mark:

B1

Calculated By:

Checked By:

Date:

Page

I. Guevarra

I. Guevarra

4/1/2013

1 of 2

DESIGN OF SINGLY REINFORCED RECTANGULAR SECTION (in accordance with NSCP 2001 Vol.1 5th edition) II. MATERIAL DETAILS/SPECIFICATION Concrete Strength fc' = B1 β1 = 250 mm Steel Strength for Main Bars fy = 400 mm Steel Strength for Stirrup fy = 40 mm 16 mm 10 mm 2 pcs 0.9 0.85

20.7 Mpa 0.85 276 Mpa 248 Mpa

Mild Steel Mild Steel

III. DESIGN LOADS FOR ANALYSIS: Negative Moment Mu neg = 55.47 KN-m Positive Moment Mu pos = 27.73 KN-m Computed Ultimate Shear Vu = 83.2 KN

I. Design of Flexural Reinforcement

Top Bars

Assumption: if fs = fy, ok! Reduction factor flexure, ø effective Depth, d Min Steel Area, Asmin Max Steel Area, Asmax Depth of compressive block a Computed Stress of Steel fs Use this as the reqd Fs Actual Steel Area Asact Remark on Asact Prefered Area of Steel As Number of reqd rebar Use this no of rebar Designed No. of steel bars spacing between bars Designed No. of layers

= = = = = = = = = = = =

= = =

0.9 360.0 456.5 2505.2 41.3 3846.74 276 658.0 Use Asact 658.0 3.273 4 5 17.5 2-layer

Bottom Bars

mm sq.mm sq.mm mm fs = fy Mpa sq.mm sq.mm pcs pcs pcs mm

0.9 360 456.5 2505.2 20.01 8573.9 276 319.0 Use Asmin 456.5 2.271 3 4 28.67 1-layer

mm sq.mm sq.mm mm fs = fy Mpa sq.mm sq.mm pcs pcs pcs mm

II. Design of Shear Reinforcement I. Shear force validation effective depth, d theoretival area of stirrup, Av Actual shear force, Vu Nomimal Shear strength of concrete Vc factored Shear strength of concrete øVc 0.5 ø Vc II. Verify if the section is adequate to carry the shear Nominal Shear strength of Stirrup Vs

= = = = = =

2/3 SQRT(fc') bw d Remark

= = =

III. Determine Stirrup spacing Computed Theoretical Stirrup Spacing, S Min allowable computed Smin Max allowable computed Spacing, Smax Prefered Stirrup Spacing, S Desinged Stirrup Spacing, S

= = = = =

360.0 157.1 83.2 68.25 58.01 29

mm

:

Theoretical Spacing is needed

sq.mm

KN KN KN KN

29.6 KN 273.0 KN Beam section is ok! 473 180 180 180 180

Remark: Vu > øVc

mm mm mm mm mm

Required Spacing: Provide : 10mmø (Fy=248 Mpa) stirrups spaced:

Rest

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