Surface [PIG]

Two types of surfaces can be defined for use in load definitions:

1. Quadrilateral: This component is typically used to define the geometry of stay-in-place formwork loads and wearing surface loads.

2. Arbitrary Polygon: While a typical quadrilateral surface is suitable for various loading geometries and can define different transverse offsets for start and end points, the arbitrary polygon is more appropriate for irregular shapes such as L-shaped loadings.