IES VisualFoundation User's Guide
Pile Supports
Piles in VisualFoundation act as anchors during the foundation analysis. Piles are defined by a location, cross-section, material, batter and length. You can specify a stiffness or use the default "rigid" stiffness of AE/L. The pile is treated as an axial-only spring element during analysis. (There are no soil-structure considerations in our pile analysis.)
A pile can be battered (i.e. not vertical) by setting the batter angle for the X and/or Y directions. This causes the axial-only spring element in the finite model to be at the batter angle and will resist both vertical and horizontal loading.
Piles cannot be loaded; you may define a pier above the pile and load that.
When performing the Sliding Stability checks for the foundation, piles can be set to have either an infinite sliding resistance (i.e. the total sliding resistance of the foundation is infinite) or a total resistance of the piles may be entered. When a total pile resistance is entered, it will be added to the frictional resistance and the passive resistance when calculating the factor of safety for sliding.
Piles represent structural members drilled or driven into the soil below the foundation. In VisualFoundation they carry only axial forces, even if they are battered. You can model concrete, steel, or wood piles with properties set from the Model & Load view. If a pile is marked as Compression Only and during the analysis goes into tension, the pile will be removed from the analysis model of that load combination, assuming failure has occurred (similarly for piles marked as Tension Only).
You specify an axial force limit for tension (uplift) and/or compression. This is the force at which the soil supporting the pile will fail and is a value you typically get from a geotechnical engineer or report. A unity check with either service or strength-level loads is performed to compare the actual demand against the specified capacity.
Design parameters, including reinforcement for concrete, are specified using the properties available from the Foundation Design view. You may specify whether your pile is braced or not for lateral buckling. We check the axial demand against the applicable limit state for the appropriate material design and the specification chosen (or shown).
Report tables, which include intermediate details are available for each check and/or limit state.