Excavation Surface¶
When you define the surface in a building excavation, you do this in two operations. First, you digitize data for the surfaces within a boundary contour in the form of points and lines. Then you add the cut and fill surfaces, that is, the transition to the terrain.
The result of the construction is two triangular networks, one for the surfaces within the boundary contour (hereinafter called the main surfaces) and one for the surfaces outside the boundary contour (hereinafter called the side surfaces).
A = Main surfaces, B = Side surfaces, C = Boundary contour
Main Surfaces¶
Points and lines (boundary contour, break lines, hole contour) with elevations are the starting point for the main surfaces in the excavation. You can enter this data foundation by typing, constructing on screen, or pasting from the clipboard (for example, copied from application layer).
When you construct points and lines on screen, you do this in the same way as when you construct in application layer. You have the same functions to generate parallels, adjust elevations to defined planes, close lines (form polygon), snap elevations to grid, and interpolate elevations to intermediate points.
Often you have a situation plan (for example in DXF/DWG format) as the starting point for the excavation. This can be, for example, excavation and blasting plans for the intervention or 3D DWG professional models. You can then place the plan as an underlay drawing and snap to points in it. It is also becoming increasingly common to receive IFC models for excavations in connection with buildings.
Side Surfaces¶
You can control how you want the transition between main surfaces and terrain. You define the side surfaces with available parameters under the Edit cut/fill parameters option.
The most relevant parameters are:
| Parameter | Description | Side |
|---|---|---|
| 0410 | Ditch 1, width | |
| 0411 | Ditch 1, slope | |
| 0511 | Rock cut 1, slope | Right |
| 0591 | Rock bench, width | Right |
| 0611 | Soil cut 1, slope | Right |
| 0711 | Fill 1, slope (low) | Right |
| 0791 | Fill 1, slope (high) | Right |
These are the same functions you use when you define the normal profile for road (Parametric method). You always enter parameters for the right side.
Application of Parameters¶
How does the program use parameters 0510 Rock cut slope, 0610 Soil cut slope, and 0710/0791 Fill slope high/low?
In a drawing, as mentioned under the chapter on data foundation, you can have up to four different layers:
- Topsoil
- Mass replacement
- Soil
- Rock
0510 Rock cut slope goes to layers 06-10: Rock. If these layers do not exist in the drawing, this parameter is not used.
0610 Soil cut slope goes to the uppermost of layers 01-05: Soil, 11-15: Mass replacement, and 16-20: Topsoil that are in the drawing.
0710/0791 Fill slope high/low goes with normal construction only to the uppermost layer in the drawing. However, it is possible to build the fill through the mass replacement layer. This is described in more detail in the section on Mass Replacement.
Build Layers¶
The program builds two triangular networks for the layer:
- 0: Main surfaces
- 1: Side surfaces (cut/fill)
These are marked in orange in the illustrations below.
0: Main surfaces
1: Side surfaces (cut/fill)
You can choose to display the triangular network on screen. Any errors are marked in the triangular network with a symbol. A typical error situation occurs with intersecting lines.
Important
Be aware that we cannot triangulate vertically, meaning that the same point cannot have two elevations. If the main surfaces span multiple levels, we cannot have vertical walls in the transitions. We must enter a small offset (dx) between top and bottom, for example 1 cm.
dx = offset between top and bottom