Reinforced Concrete Beam Module - Calculation of Beam Size

Calculation of Beam Size

How do you calculate beam size?

1. Download this calculation spreadsheet in free.
2. Open this sheet in MS Excel software.
3. Insert design data, beam data and reinforcement data.
4. Then click 'RUN ANALYSIS" and see the beam size result.

Default Design Data:

Design Moment, M = 18 KN-m

Design Shear at Support (for stirrups calculation), V = 87 KN.

Effective Length of Beam (for stirrups calculation), L = 5 m.

Reinforcing Bar Yield Strength, fy = 275 MPa.

Concrete Compressive Strength, fc' = 20.7 MPa.

Beam Data:

Depth of Beam, h = 250 mm

Width of Beam, b = 200 mm

Clear Covering, c = 38 mm

Steel Reinforcement data:

Number of layers for tensile bars (max=2 layers) NLay = 1 layer(s).

• First layer bars

Number of Reinforce Bars (1) N = 2 pc(s).

Bar (1) Size dia = 16 mm.

The number of Reinforce Bars (2) N = 0 number error.

Bar (2) Size dia = 0 number error.

• Second layer bars

The number of Reinforce Bars N = 0 number error.

Bar Size dia = 0 number error.

• Compressive bars

The number of Reinforce Bars(one layer only) 2 pc(s).

Bar size dia = 16 mm.

Stirrup Bar Diameter dia = 10 mm.

Result of Beam Design

Beam Design in Excel Spreadsheet

DESIGN NOTES:

• Minimum Cover for cast in place concrete as recommended by ACI
• Beams/Columns - 40 mm
• Slab/Wall/Joist - 20 mm-40mm (depending on bars sizes) 
• If exposed to weather, Beams/Columns - 40mm-50mm
• Slab with beams on four edges - 90mm

Download free excel spreadsheet here: Calculation of Beam Size Excel Spreadsheet. You can also free download Foundation Desing Excel Sheet on this website. For any question, white in the comment box, Thank you.