Isolated Column Footing Design in Excel - USD Method

Isolated Column Footing Design in Excel
Isolated Column Footing Design in Excel

Hi, I'm Engr. Bala Ram. Today I share an Isolated column footing design calculation excel sheet in free. This design calculated in the Ultimate Strength Design method.

How to design isolated column footing in an excel sheet:

Step - 1: Insert data like fig-01
Footing Design in Excel step-1

Step - 2: Footing Size

Since the space between the bottom of the footing and the surface will be occupied partly by concrete and partly by soil (fill), the average unit weight of 125 lb/ft3 will be assumed.
Step - 2: Footing Size


Step - 3: Thickness

Assuming, d = 20.50  in ( assuming sum of (L+B) in the unit of inch)

Step - 4: Punching Shear Check

Factored Load from Colm, Pu = 494.00 kip (Taken from Staadpro)
Upward pressure caused by the factored load of the column,      qu = Pu / (LxB) = 5.78 ksf.
The footing depth in square footings is usually determined from the two-way or punching shear on the critical perimeter "abcd". Trial calculation suggests d = 20.50 in.
Punching Shear Check

Step - 5: Beam Shear Check in the Long direction (L)
The selected value d= 20.50 in will now be checked for one-way or beam shear on section "EF". 
The factored shear force acting on that section is:-
Beam Shear Check in the Long direction


Step - 6: Beam Shear Check in the Short direction (B)

The selected value d= 20.50 in will now be checked for one-way or beam shear on section "IJ". 
The factored shear force acting on that section is:-
Beam Shear Check in the Short direction

Step - 7: Bending Moment in the Long direction (L) or on section "GH"
=  5858666.67 lb-in

Step - 8: Bending Moment in the Short direction (B) or on section "KL"
Bending Moment in the Short direction

Step - 9: Check "d" considering Max moment
considering Max moment

Step - 10: Steel requirements in the Long Direction (L)
Steel requirements in the Long Direction
Step - 11: Steel requirements in the Short Direction (B)
Steel requirements in the Short Direction
shall be uniformly distributed across a bandwidth, B centered with respect to the column and having a width equal to the length of the short side of the footing, The reminder of the reinforcement shall be uniformly distributed in the outer portion of the footing.

Steel requirements in the Short Direction

Step-12: Development Length for footing in the long direction (L)
Development Length for footing in the long direction


Step - 13: Development Length for footing in the Short direction (B)

Development Length for footing in the Short direction


Step - 14: Development Length for Column

Development Length for Column
Step - 15: Final Design

Isolated Column Footing Design in Excel - USD Method
Isolated Column Footing Design in Excel - USD Method
Download and open this spreadsheet here: Excel File. You also know how to design Wall Footing in Excel Sheet USD method. If any problem for calculated this design, comment below, Thank you.

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