Parameters such as compressive strength, unit weight, pier and footing concrete cover over rebars, and allowable increases may be set here. If in App Settings, the values entered here will become the defaults for all subsequent new projects.
Concrete Cover
The concrete cover implies clear distance between the rebar and the edge of concrete. For e.g. the concrete cover in the pier implies the clear distance between the tie bar and the edge of concrete. For a soil-supported foundation, the bottom cover is the clear concrete cover between the steel and the bottom of the footing. For a pile-supported foundation, the bottom cover is the clear concrete cover between the steel and the top of the pile.
Note: The program uses the allowable increase in concrete stress due to short-term loads to compute the wide beam shear and the punching shear in the footings. If you multiply the load combinations containing short term loads by a reduction factor such as in a combination of the following type: 0.75*(1.4Dead + 1.7Live +1.7Wind), do not allow for an increase in the allowable stress.
Enable Pier Concrete Design
When this option is checked, all the piers in the current workspace are selected to undergo concrete capacity design. You may want to uncheck this option when there are significant number of piers and a significant number of load combinations to reduce the total calculation time in the initial phase of a foundation design. Once the footing design is close to being finalized, you can check this option to complete the pier concrete design.
Shear Enhancement Factor Close to Support
This factor allows an increased allowable beam shear stress value when checking shear stress values close to supports. The default value is 1. Any value between 1 & 2 may be entered. The basic or design shear stress is calculated at the code specific critical section. This basic or design shear stress is then multiplied by the shear enhancement factor * d/av if applicable. For eg if the shear enhancement factor to be considered is 2*d/av where d is the effective depth at the critical section being considered and av is the distance from the face of the support as defined by the selected concrete design code for soil or pile supported footings, then specify a factor of 2. If the shear enhancement factor to be considered is 1.5*d/av then specify a factor of 1.5. The final allowable shear stress then would be = the basic or design shear stress * shear enhancement factor * d/av.
This factor will be used for BS, CP, Euro, IS & AS codes. This factor will not have any impact on the allowable beam shear stress values for ACI, CSA & IBC codes. This factor will be used for both soil and pile supported foundations.
Distance to Effective Depth Ratio where Shear Enhancement should be considered
This factor allows shear enhancement to be considered for pile supported foundations when a pile or a line of piles close to the support face falls within the distance specified by this factor. For eg if this factor is 2, and if the piles are within a distance of 2*d (where d is effective depth) then shear enhancement is considered. If all piles fall outside 2*d then shear enhancement will not be considered. Also shear enhancement is considered only if all the piles within the specified distance are in compression.
Use separate concrete parameters for piers and footings
This option on the Concrete page of workspace settings allows using different concrete parameters - compressive strength and unit weight of concrete for the footing and the piers. The section called "Concrete Parameters" on this page are parameters that will be use for footing design. When this option is checked, another section called "Pier Concrete Parameters" displays which are the parameters that would be used for pier design.
If this option is unchecked, the pier and footing design are both based on the parameters specified under "Concrete Parameters".
Light weight concrete
If lightweight concrete must be used for a foundation design project, select or check the option "Use Lightweight Concrete". Specify a concrete density modification factor less than or equal to 1 for use with lightweight concrete. Some concrete design codes do not have lightweight concrete provisioning. In this case selecting this option will not have any impact on the calculation results.