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Individual 'Pad Footing' Table
Tables are shown for f'c Concrete at 2000 psi and 3000 psi |
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f'c = 2000 psi Concrete
psi = pounds per square inch Footing Width = Square Footings, where Both sides of Footing have same dimension |
f'c = 3000 psi Concrete
psi = pounds per square inch Footing Width = Square Footings, where Both sides of Footing have same dimension |
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Maximum Soil Pressure (lb/sq.ft.) |
Plate or Column Width (inches) |
Allowable Load on Footing (kips) |
Footing Thickness (inches) |
Footing Width (inches) |
Reinforcing Each Way |
Allowable Load on Footing (kips) |
Footing Thickness (inches) |
Footing Width (inches) |
Reinforcing Each Way |
| 1500 psf | 8" | 12.4 | 10" | 3'-0" | 3 No. 3 | 12.4 | 10" | 3'-0" | 3 No. 3 |
| 8" | 16.8 | 10" | 3'-6" | 3 No. 4 | 16.8 | 10" | 3'-6" | 3 No. 4 | |
| 8" | 22 | 10" | 4'-0" | 4 No. 4 | 22 | 10" | 4'-0" | 4 No. 4 | |
| 8" | 28 | 10 | 4'-6" | 4 No. 5 | 28 | 10" | 4'-6" | 4 No. 5 | |
| 8" | 34 | 11" | 5'-0" | 5 No. 5 | 34 | 10" | 5'-0" | 6 No. 5 | |
| 8" | 48 | 12" | 6'-0" | 6 No. 6 | 49 | 11" | 6'-0" | 6 No. 6 | |
| 8" | 65 | 14" | 7'-0" | 7 No. 6 | 65 | 13" | 7'-0" | 6 No. 7 | |
| 8" | 83 | 16" | 8'-0" | 7 No. 7 | 84 | 15" | 8'-0" | 7 No. 7 | |
| 8" | 103 | 18" | 9'-0" | 8 No. 7 | 105 | 16" | 9'-0" | 10 No. 7 | |
| 2000 psf | 8" | 17 | 10" | 3'-0" | 4 No. 3 | 17 | 10" | 3'-0" | 4 No. 3 |
| 8" | 23 | 10" | 3'-6" | 4 No. 4 | 23 | 10" | 3'-6" | 4 No. 4 | |
| 8" | 30 | 10" | 4'-0" | 6 No. 4 | 30 | 10" | 4'-0" | 6 No. 4 | |
| 8" | 37 | 11" | 4'-6" | 5 No. 5 | 38 | 10" | 4'-6" | 6 No. 5 | |
| 8" | 46 | 12" | 5'-0" | 6 No. 5 | 46 | 11" | 5'-0" | 5 No. 6 | |
| 8" | 65 | 14" | 6'-0" | 6 No. 6 | 66 | 11" | 6'-0" | 7 No. 6 | |
| 8" | 88 | 16" | 7'-0" | 8 No. 6 | 89 | 15" | 7'-0" | 7 No. 7 | |
| 8" | 113 | 18" | 8'-0" | 8 No. 7 | 114 | 17" | 8'-0" | 9 No. 7 | |
| 8" | 142 | 20" | 9'-0" | 8 No. 8 | 143 | 19" | 9'-0" | 8 No. 8 | |
| 10" | 174 | 21" | 10'-0" | 9 No. 8 | 175 | 20" | 10'-0" | 10 No. 8 | |
| Caution! Care needs to be taken when using the tables. You must be sure of what type of loading you are going to place over the footings and what is the soil bearing capacity. If you do not know be sure ask your Engineer or Architect. | |||||||||
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Definitions:
f'c = 2000 psi (Concrete Strength), Example: When Ordering Concrete simply specify 2000 psi concrete, or what ever is the required Concrete you will be using. Soil Pressure = the capacity of the soil to resist a load placed on it. Column or Plate Width = The Square size of the Column or Plate that will be in contact with the top of the Footing. Allowable Load on Footings = This is the Total Load that comes down the Column to the top of the Footing. Footing Thickness = How thick the Footing must be from the top of the concrete to the bottom of the concrete. Footing Width = How wide and how long the Footing must be. These Footings are square footings, which means they have the same dimension on both sides. Reinforcing Each Way = The size and the number of steel reinforcing bar that are required in each Pad Footing. For Example: 4 No. 5 means use 4 steel bars (rebars) of the number 5 size. The placing of the rebars are to be a mimimum of 3 inches from the dirt on the bottom of the Pad Footing and 3 inches clear of the side dirt walls. The bars are placed in a checker board pattern and tie together with bailing wire at the points where they intersect. The spacing between each rebar should be equal. A piece of concrete block or a metal piece, called a chair, should support the rebars at least 3 inches off the bottom of the hole for the Pad Footing. Pad Footings must be physically connected to a Column. The type of Column used will require that you install either dowels (bent steel rebars extending from the Pad Footing into the Concrete Column) or J-Bolts if you are using a Steel Column with a Steel Plate. Once all of this is done, you need to call the Building Department to request for a Footing Inspection. Once the Footing has been inspected by the Building Official and he or she approve the installation, you may now call the Concrete Plant to deliver the Concrete for you Footing. If you intend to make your Concrete, be sure to speak to your Building Official, because the Strength of the Concrete is based on the proportions of mixture of cement, sand, aggregate (rocks) and water. Any variation in the mixture content will change the Strength of the Concrete, so be careful. Check if your Building Department will allow you to use a Premixed Concrete which come in bags and can be purchased a local Lumber Yard or Hardware Store. When using Premixed Concrete Bags, you must be aware of how much water you can add to the Premix, since the amount of water will also affect the Strength of the Premixed Concrete. Loading Conditions: (where, psf = Pounds per Square Feet = lb/sq.ft.) The design of footings require that you know what is the capacity of the soil. The tables shown are for two assumed soil bearing capacities (1500 psf and 2000 psf). If your soil has a larger bearing capacity, you will find that when you have the Loads Calculated, the footing size will be smaller. If you do not know what the soil capacity is for you project, be sure to get help. These Tables are to be used to Estimate the Footing Needed for Construction and MAY ONLY BE USED FOR DESIGN BY SOMEONE WHO HAS THE KNOWLEDGE AND EXPERIENCE IN CONSTRUCTION. |
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