> 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-backfill-rw.md).

# Retaining Wall Backfill \[RW]

The Retaining Wall Backfill object computes the backfill placed behind a wall segment, measured between the wall and the finished grade surface. It is used for earthwork quantity take-off.

## General

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

**Finished Grade (DTM):** Digital terrain model representing the finished grade surface. The backfill volume is measured up to this surface.

**Boundary Offset Beyond Footing Heel:** Horizontal distance the backfill extends beyond the heel of the footing (default: 12).

## Display

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

**Opacity:** Opacity used when drawing the backfill solid (default: 0.5).

## Quantities

**Gross Backfill Volume:** Computed backfill volume, before deducting any structure volume. (Read-only)

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

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

## IFC

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

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


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