[ERROR] FOOTING HAS FAILED THE CHECKS FOR THE CURRENT LOAD CASE BECAUSE CORNER PRESSURES HAVE EXCEEDED THE SOIL BEARING CAPACITY, OR, MINIMUM CONTACT AREA REQUIREMENTS WERE NOT MET.

In recent versions of the program, you ought to see messages that indicate which load case was last solved before a failure took place, and the kind of calculation that was being performed when the failure occurred. When a failure occurs, either the number of errors or warnings or both will be a non-zero value and you ought to be able to scroll through those messages to see what the error or warning is.

For example, if an error or warning immediately follows something like the following statement

[INFO] PROCESSING LOAD COMBINATION 104 FOR SLIDING/OVERTURNING WITH LENGTH = 5000.0000, WIDTH = 5000.0000, DEPTH = 700.0000

it means the failure occurred during a sliding/overturning check for load case 104, and the program has reached the limits as far as it can go towards increasing the plan dimensions.

Or if you see a message along the lines "FAILED IN ONEWAY SHEAR, MAXIMUM PERMISSIBLE DEPTH EXCEEDED"

[INFO] PROCESSING LOAD COMBINATION 227 FOR ULTIMATE DESIGN WITH LENGTH = 5000.0000, WIDTH = 5000.0000, DEPTH = 700.0000
[INFO] BENDING MOMENT ABOUT LOCAL X AXIS = 95.163710 KN-M
[INFO] BENDING MOMENT ABOUT LOCAL Z AXIS = 72.734804 KN-M
[INFO] ONEWAY SHEAR FORCE - LOCAL YZ PLANE = 55.010776 KN
[INFO] ONEWAY SHEAR FORCE - LOCAL XY PLANE = 68.263674 KN
[INFO] PUNCHING SHEAR FORCE = 243.104089 KN

then, the limit has been reached for all three sides.

Make sure that the values you have specified for the various parameters are consistent with the units in which they are specified. For example, unit weight of concrete should generally be in the range 15 to 35 kN/m3. So, if the number is 25, but the units are kN/mm3, that could cause an unsuccessful design. A number of checks have been added to the program to identify such input errors, and you ought to see warnings in such instances.

Here are reasonable values for the other input terms:

Compressive strength for concrete and yield strength for steel should be between 15 to 75 and 200 to 700 N/mm2. Clear cover - 25 to 100 mm, bar spacing - 50 to 500 mm, Bearing capacity of soil - 100 to 500 kN/m2, Height of soil above footing - 0 mm to 10000 mm, surcharge pressure - 0.0 to 10 kN/m2, footing plan dimensions - 1000 mm to 20,000 mm (minimum to maximum), footing thickness - 200 mm to 1000 mm, factor of safety in sliding and over turning - 1.0 to 3.0, Coefficient of friction between soil and concrete : 0.1 to 0.6, etc. These are just recommended values. There may be special situations where values may be outside these ranges.

Another common mistake that we have found in many models : Including all load cases (basic cases and combinations) in the job. Include only the combination cases in the job. Never include a pure lateral case like wind only or seismic only case. Such cases may not have sufficient "P" to mobilize sufficient resistance for sliding and overturning.

If the above information isn't giving you sufficient clues to find the reason, please attach the .SFA model.