| Include Moment Due to Shear in Column for |
In footings supporting frame columns, the column shear induces an additional moment into the footing equal to the column shear times the footing thickness. In some cases this additional moment can be ignored in the design of the footing if there is some other mechanism (such as a floor slab) provided to take the shear. This criterion gives the engineer the option to include or ignore the moment due to the column shear when designing footings and can be specified separately for Spread Footings, Continuous Footings, and Pile Caps.
Note: This option does not cause the program to ignore the column moments on the footing; it only causes the program to ignore the additional moment resulting from the footing thickness.
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| Include Spread Footing Self-Weight When Checking Soil Stress |
This criterion gives the engineer the option to include or ignore the spread footing self-weight in the calculation of the soil stress. It is common to have a soil report state that the given soil capacity accounts for the footing self-weight. In this case it is not necessary to include the footing self-weight when checking the soil stress. |
| Keep Spread Footing Square During Optimization |
This criterion provides the opportunity to force spread footings to remain square during optimization. Selecting this option forces both plan dimensions to be increased equally if either of the plan dimensions need to be increased to satisfy the code design checks. This is done until the maximum dimension limit in either direction is reached. |
| Increase Spread Footing Size to Prevent Uplift in Concrete Load Combinations |
When the program optimizes the sizes of spread footings, it will increase the size of the footing, if necessary, so that there is no net uplift present in any of the Concrete Load Combinations (with a factor of safety against uplift as explained in Net Uplift
). When the option is deselected, the footing size is not increased to counter the uplift from the column axial load in the concrete load combinations. In this case, for a given concrete load combination that produces a net uplift on the footing, the footing is designed only to resist the factored self-weight and surcharge on the critical sections. Note that this will produce flexural reinforcement in the top of the footing.
When moments are applied to the footing through the supported column, the user's selection may be overridden by the program. If moment is present at the base of the supported column, the footing will be upsized as described above even if the user has not selected the option to do so. This is done so that the analysis conducted in RAM Foundation is consistent with the forces obtained from RAM Frame or RAM Concrete, in which the column base is always assumed fixed against translation in the vertical direction.
Note: Consider a spread footing that is optimized with this option selected. Any subsequent change made to the footing geometry within the View/Update dialog that produces net uplift in any of the Concrete Load Combinations will not produce a warning message.
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