> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/templates/retaining-wall-workflow/earthwork-rw/retaining-wall-excavation-rw.md).

# Retaining Wall Excavation \[RW]

The Retaining Wall Excavation object computes the excavation required to build a wall segment, measured between the existing ground surface and the underside of the footing. It is used for earthwork quantity take-off.

## General

**Wall Segment:** The wall segment the excavation is computed for.

**Existing Ground (DTM):** Digital terrain model representing the existing ground surface. The excavation volume is measured down from this surface.

**Boundary Offset Beyond Footing:** Horizontal distance the excavation extends beyond the footing edges, providing working room (default: 12).

**Over-Excavation Below BOF:** Additional excavation depth below the bottom of footing, for example to remove unsuitable material (default: 0).

## Display

**Show Excavation\[No=0/Yes=1]:** When Yes, the excavation solid is drawn in the 3D view (default: Yes=1).

**Opacity:** Opacity used when drawing the excavation solid (default: 0.6).

## Quantities

**Excavation Volume:** Computed excavation volume. (Read-only)

**Top Surface Area:** Area of the top surface of the excavation. (Read-only)

**Bottom Surface Area:** Area of the bottom surface of the excavation. (Read-only)

## IFC

**Type:** IFC entity used when exporting the earthwork solid.

**Predefined Type:** IFC predefined type. Default `EARTHWORKS_EXCAVATION`.


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