What makes Unique of RC…?
It is a COMPOSITE MATERIAL…
- It requires APPLICATION of more involved Principles of Mechanics…
- Structural Design is iterative requiring both ANALYSIS and DESIGN DECISIONS aided by judgment and EXPERIENCE.
- ACI 318 -the model code in the United States of America for guiding the design of RC members, look at Chapter 8.
- NSCP Code -the code in the Philippines..conforms to the provisions of ACI 318 Code!!!
Important Material Properties…
Concrete Strength and Steel Strength…
- 28-day Compressive Strength, f’c: ACI 318 Code 2011 edition, Chapter 5.
- Modulus of Elasticity of Concrete, Ec: ACI 318 Code 2011 edition, Chapter 8.5
- Strength property or yield strength, fy..
- Modulus of Elasticity of Steel, Es: 29,000,000 psi –ACI 318 Code 2011 edition.
1. –Procedures on how to Design Reinforced Concrete Beams!!!
Concrete Beam Sizing..!
Beam Section Diagram
Determination of Beam Size (b x h)—USE Spreadsheet or Hand Calculation!!!
Concrete Beam Size (b x h) or (b x d), FORMULA:
Beam Size Formula
Beam Section, Strain and Force Diagram
Equilibrium Equation orm Neutral Axis Distance, c — Quadratic Equation for c
Area of Steel (As) determination!!!
The ACI Code 10.3.3 to 10.3.5 limits on the Steel Ratio (rho):
1.1 Minimum Beam Size for which Deflections are NOT LIKELY to be a Problem.
1.1.1 Set Neutral Axis distance, c = 0.375cb….
Smallest Beam Size NOT LIKELY TO HAVE DEFLECTION PROBLEM
1.2 Arrangement of Rebars, Splicing points and splice length, development length, hooks requirement, and required Stirrups.
Stirrup Spacing Requirements per ACI
Stirrup Maximum Spacing
ACI Bottom Bar Splice Requirements
ACI Standards for Top and Bottom Splice Requirements
ACI Standards for Beams Reinforcements
2. –Procedures on how to Design Reinforced Concrete Columns!!!
Tie Design Standards
ACI Standards Columns Bars Details
ACI Column Splice Details
ACI Bar Bending Details
ACI Bar Bending Details
ACI Column Ties Requirements
2.A. –Structural Design for column using Interaction Diagram!!!
Interaction Diagram plot using Column design software and MS Excel Spreadsheet
2.B. –Example of ACI Interaction Diagram.
Interaction Diagram-Rectangular Section-Courtesy of ACI
Interaction Diagram-Spiral Column-Courtesy of ACI
2.C. –Summary of Column Design Requirements!!!
Column Design Requirements
2.1 Strength Reduction Factor, phi =0.70 -applicable up through ACI 318-1999; they have been changed to phi =0.65, for compression controlled members (columns and beams under compression controls) beginning with ACI 318-2002 Code, and continuing with the ACI 318-05 and 2008 up to present.
3.–Example: Design of Concrete Members, i.e. Frame Analysis, Beams, Columns, Footings using MS Spreadsheet.
FRAME ANALYSIS-My own Spreadsheet Program
MS Excel Spreadsheet for Column
Column Excel Spreadsheet
- Design of Reinforced Concrete by Jack. C. McCormc, 3rd edition-1993, 7th edition-2005, 9th edition-2011;
- Design of Concrete Structures by Arthur H. Nilson, 12th edition -1997, International edition;
- Design of Concrete Structures by Arthur H. Nilson, 14th edition -2010, International edition;
- Reinforced Concrete (A Fundamental Approach), by Edward G. Nawy, 6th edition -2008,
- Reinforced Concrete, Mechanics and Design, by James K. Wight and James G. MacGregor, 6th edition -2012,