# 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](https://gitbook.saf.guide/structural-analysis-elements/structuralsurfacememberregion#region-of-different-plate-thickness)) must be defined inside the main slab. ![](https://2984879901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FP3f3I86mz7TGPX0pWLAB%2Fuploads%2Fgit-blob-004d23056815d161e62ebf639a85e34a781f8812%2F35_structuralsurfaceaction.png?alt=media) ### 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 |

X

Y

Z

| 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 |

On 2D member

On 2D member region

On 2D member distribution

| 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](https://gitbook.saf.guide/loads/structuralsurfaceactiondistribution-1) 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 |

Global

Local

| yes | Defines the co-ordinate system of the member in which the load is applied | | Location | Enum |

Length

Projection

| 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 |

Is filled for objects created be dividing curved geometry to series of straight line objects.

Parent ID will ensure that curved edge is imported as straight parts to nonsupporting application, and back to original supporting application as curved geometry.

To ensure successful round trip of segmented objects and their related objects, Parent ID needs to be present in both directions.

| | Id | String | 39f238a5-01d0-45cf-a2eb-958170fd4f39 | no | Unique attribute designation |