# StructuralSurfaceAction

## Surface load

Defines actions on surfaces – plates, walls. The surface load is defined on the whole slab automatically. If only a part of the main slab is supposed to be subject to this load, a subregion ([StructuralSurfaceMemberRegion](/structural-analysis-elements/structuralsurfacememberregion.md#region-of-different-plate-thickness)) must be defined inside the main slab.

![](/files/tMCIk4kYOASY4MnUdRAH)

### Specification in the excel

| Name of the column header | Type of data |                        Value example or enum definition                       | Required value                                | Description                                                                                                                                                                                                                                                                                                                                                                                                            |
| ------------------------- | ------------ | :---------------------------------------------------------------------------: | --------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Name                      | String       |                                      PF3                                      | yes                                           | Human readable unique name of the force                                                                                                                                                                                                                                                                                                                                                                                |
| Direction                 | Enum         |                            <p>X</p><p>Y</p><p>Z</p>                           | yes                                           | Specifies the base direction of the load                                                                                                                                                                                                                                                                                                                                                                               |
| Type                      | String       |                                    Standard                                   | no                                            | This property defines what the load is caused by, E.g. Standard, Wind, Snow, Self weight, Hoar Frost, Predefined, Plane Load, Water Pond, Water Pressure, Soil Pressure, Generated Water, Generated Soil                                                                                                                                                                                                               |
| Force action              | Enum         | <p>On 2D member</p><p>On 2D member region</p><p>On 2D member distribution</p> | yes                                           | Specifies on which type of object the load acts                                                                                                                                                                                                                                                                                                                                                                        |
| Value \[kN/m2]            | Double       |                                      -10                                      | yes                                           | Specifies the size of the load in kiloNewtons per square meter.                                                                                                                                                                                                                                                                                                                                                        |
| 2D Member                 | String       |                                      S15                                      | yes, if Force action = On 2D member           | The name of the [StructuralSurfaceMember](https://saf.guide/Content/A_Objects/8_StructuralSurfaceMember.htm) to which is the surface load related to                                                                                                                                                                                                                                                                   |
| 2D Member Region          | String       |                                       R1                                      | yes, if Force action = On 2D member region    | The name of the [StructuralSurfaceMemberRegion](https://saf.guide/Content/A_Objects/10_StructuralSurfaceMemberRegion.htm) to which is the surface load related to                                                                                                                                                                                                                                                      |
| 2D Member Distribution    | String       |                                      FL1                                      | yes, if Force action = 2D Member Distribution | The name of the [StructuralSurfaceActionDistri](/loads/structuralsurfaceactiondistribution-1.md) to which is the surface load related to.                                                                                                                                                                                                                                                                              |
| Load case                 | String       |                                      LC5                                      | yes                                           | The name of the load case to which the force belongs                                                                                                                                                                                                                                                                                                                                                                   |
| Coordinate system         | Enum         |                           <p>Global</p><p>Local</p>                           | yes                                           | Defines the co-ordinate system of the member in which the load is applied                                                                                                                                                                                                                                                                                                                                              |
| Location                  | Enum         |                         <p>Length</p><p>Projection</p>                        | yes                                           | Specifies whether the load is "put directly on an inclined 2D member" or whether the "projection on plan" is defined.                                                                                                                                                                                                                                                                                                  |
| Parent ID                 | String       |                      67b35d84-3d04-47aa-aa4a-dc1263982320                     | no                                            | <p>Is filled for objects created be dividing curved geometry to series of straight line objects.<br><br>Parent ID will ensure that curved edge is imported as straight parts to nonsupporting application, and back to original supporting application as curved geometry.</p><p>To ensure successful round trip of segmented objects and their related objects, Parent ID needs to be present in both directions.</p> |
| Id                        | String       |                      39f238a5-01d0-45cf-a2eb-958170fd4f39                     | no                                            | Unique attribute designation                                                                                                                                                                                                                                                                                                                                                                                           |


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