Calculate Model

The Calculate Model button evaluates the foundation system’s performance under service load combinations. To achieve this, the software generates a comprehensive analytical model of the foundation system.

Finite Element Modeling (FEM)

The foundations are modeled using Q3 shell elements. These are triangular finite elements with three degrees of freedom (DOF) at each node:

• Displacement in Z
• Rotation about X
• Rotation about Y

The triangular mesh is generated based on a hexagonal grid of equilateral triangles. The edge length is defined by the “Mat & Strip Mesh Size” parameter (located in Project Settings), with a default value of 0.3m. This grid is automatically refined in the vicinity of load points to ensure accuracy.

Load Application

The foundation system is subjected to various load types, which are applied as follows:

1. Distributed Area Loads:
   • Source: Soil weight and the foundation’s self-weight.
   • Application: These loads are assumed to be uniform and are assigned to each node based on its tributary area.
2. Lateral Soil Restraint (Line Loads):
   • Source: The passive pressure or restraint provided by the surrounding soil.
   • Application: This is applied as a linearly distributed load to nodes along the edges compressed by the soil, based on their tributary width.
   • Calculation: The software determines the resultant force on the foundation and projects it onto the outward normal vector of each edge. This process identifies which edges are under compression and quantifies the magnitude of the restraint.
3. Pedestal Loads (Point Loads):
   • Source: Concentrated loads from the superstructure.
   • Distribution: Point loads are distributed across 5 specific points on the pedestal footprint:
     • 2/6 of the total load is assigned to the pedestal’s center point.
     • 1/6 of the total load is assigned to each of the four corners.