STAAD Foundation Advanced Help

Design Parameters page

Design parameter is grouped under three categories. They are Material Density, Bearing and Stability and Concrete Design Parameters

Setting	Description
Number of Increments Along the Pile	Type the number of discrete sections along the length of the pile at which a analysis is performed.

Setting	Description
< Previous	Steps the Wizard to the previous step.
Cancel	Exits the Wizard without creating a new Drilled/Driven Pier job.
Finish	Closes the Wizard and creates the Drilled/Driven Pier job in the current project

Reinforcement

Setting	Description
Reinforcement Strength	Type the yield strength of steel reinforcing bars (f_y), in the selected units.
Modulus of Elasticity	Type the Young's Modulus of steel reinforcing bars (E), in the selected units.
Min / Max Bar Size	Select the minimum and maximum allowed reinforcing bar sizes to be used in the design.
Max Spiral	Type the maximum size to use for spiral confinement steel.

Concrete

Setting	Description
Concrete Strength	Type the ultimate strength of the concrete (f'_c), in the selected units.
Modulus of Elasticity (Concrete)	Type the Young's Modulus of concrete (E), in the selected units.
Concrete Density	Specify a density to be used for concrete (w_C), in the selected units.

Critical Depth for Axial Capacity

Setting	Description
Critical Depth Ratio Calculation	Select to either have the program Calculate the critical depth or to type the value as User Input.
Critical Depth Ratio	(User Input only) Soil depth at which vertical stress appears to become constant is known as the Critical Depth. This value is the ratio of critical depth to the pier diameter. Typical range of critical depth ratio lies from 10 to 20.

Pile Condition

Setting	Description
Pile Batter Angle	For battered piles, type the angle between vertical and the centerline of the pile, in degrees.
Ground Slope Angle	Type the angle between horizontal and the surrounding ground slope, in degrees.

Axial Load Parameters

Setting	Description
F.S. End Bearing	Factor of safety for base resistance.
F.S. Skin Friction	Factor of safety for side resistance.
Tip Resistance % for Axial Capacity	Percentage of base resistance (end bearing) force to be considered in axial capacity.
Skin Resistance % for Axial Capacity	Percentage of the maximum skin friction that is being developed as a function of downward deflection of the pile, where that downward deflection has been normalized to units of pile diameters.
Neglected Top Soil Layer for Skin Friction	For top layer skin friction, typically first five feet are neglected. Additionally, any backfill layer should be neglected for skin friction. Note: Neglected soil zone at top at bottom are regions excluded from skin friction calculation.
Neglected Bottom Soil Layer for Skin Friction	For bottom layer skin friction, in case of Straight pier profile typically soil layer equal to one pier diameter thickness is neglected and in the case of Belled pier profile, a soil layer equal to sum of bell periphery and pier diameter is neglected.