Zones (object data)

Default Colors of Zones

When creating and editing zone colors the Quantm Desktop software uses a pre-defined palette to color the hatching of zones depending on their nature. For example, a water zone will be blue and a crossing zone will be yellow. The default palette for the zone’s colors can be edited in the Preference Settings dialog box by selecting the Zones tab. See Preference Settings.

Create a zone

To create a zone:

1. On the Insert tab, click the Create Zone button.

2. Select the type of zone. The appropriate dialog appears.

3.  Name the zone and enter its properties. Properties vary depending on the type of zone created. Select a layer from the Layer list to store the zone. See the examples for each zone type below.

4.  Trace the boundary of the zone in the Plan view by using the left mouse button. Double-click or press [Enter] to finish the definition of the zone. There is no need to close the zone, the system will close the zone automatically.

Caution: Create zones at least 100 meters square. Zones smaller than this may not be recognized by the optimizer and have no effect on the generated alignment. Clusters of small zones should be consolidated into a larger zone.

Avoid zones

Avoid zones are used to keep alignments out of areas of environmental, social, or heritage significance. There are three avoid zone types with differing priorities: high, medium, and low. The default avoid zone priority is high. If the location of the avoid zones is such that an alignment cannot fit between them, some can be “sacrificed” by giving them medium or low priority. The alignment will still try to minimize the extent of the intrusion, but will enter them in preference to high priority zones.

Create an Avoid zone

1. On the Insert tab click the Create Zone button. Choose Avoid.

2. The Layer field is set to Avoid but it can be placed in any existing layer by clicking on the drop down list.

3. Set the level of priority:

• Apply High priority avoid zones to regions into which alignments cannot enter under any circumstances.

• Apply Medium or Low priority avoid zones to regions into which alignments can enter, perhaps resulting in reduced costs or improvements to the geometry.

4. Click OK.

Tip: To create an object in a new layer that does not exist, type the name for a new layer in the Layer field while setting the properties of your feature.

Crossing zones and Water zone

A Water zone is the same as a crossing zone, however when it is created the properties of the zone will visually appear as a water body in the ‘nature’ field. By default, the color of the zone will be either blue for water or yellow for crossing.

1. Follow the steps for Creating a zone. Select crossing or water for the zone type.

2. The Layer field is set to Crossing or Water but it can be placed in any layer by clicking the drop-down list.

3. The Reference Altitude field options are; Local low, Mean sea level, and Natural Surface.

• The Local low is the lowest point on the DTM within 100 meters of the road being optimized.

• The Mean sea level uses an absolute height above zero, this being the elevation at sea level.

• The Natural surface is determined using the terrain model.

4. In the Crossing type field:

• Select the relevant type from the drop-down list. The options are; Unspecified Bridge, Tunnel, Structure (zone), Culvert, Wall on fill, Wall in cut, and Wall always.

• To use the most economical means for crossing the area, select Unspecified. The most economical crossing type is normally earthworks, but (in some cases) it is more cost-effective to cross using a structure.

• In an area where a particular crossing clearance is required, but where a crossing does not impact the type of construction, select Unspecified. For example, crossing a buried pipeline affects the clearance but not the type of construction.

5. If you selected a crossing type other than Unspecified, select a structure type from the list:

Note: What you select here overrides the local default structure type. Select Unspecified to retain the local default structure type.

6. Trace the boundary of the zone on the Plan view, Double-click to stop the trace. There is no need to close the zone.

To edit these settings, see Global Zones.

Using a Culvert as a Crossing type

A culvert is a crossing type in the crossing zone. Use this crossing type in a flat area that sometimes has sheet flows of water. The alignment is generally on an embankment that has to accommodate a specified number of culvert cells per km to allow the water to pass under the route. These culverts are usually located where the alignment crosses dips, and if the mean separation of cells is, for example, 200 m (5 cells per km), the minimum separation of cells is half that - 100 meters.

To define a culvert, set the Crossing type field to Culvert:

Crossing zone example

A flood area is another way of using the Crossing zone. Flood areas can be defined by using a crossing type that can be built above ground; Bridge, Structure (zone), Tunnel, or Culvert.

Insert a flood area in an area where the road or railway has to stay above likely flood levels. For example, you might define a flood zone:

• In a river valley. Because the valley floor drops as the river flows downstream, the potential flood levels also drop.

• In an open area, twenty kilometers or more across, that has a relatively gentle slope and an occasional low ridge.

Neither of these lends itself to a defined height above sea level or to a defined height above the natural surface. Instead, define a flood zone by setting the reference altitude to Local low point for the Bridge, Structure (zone) or Tunnel crossing types. The local low point is the lowest point on the DTM within 100 meters of the road. If you apply a clearance of 5 meters above the local low point, every point on the alignment will be at least 5 meters above the lowest point that is within 100 meters of the local low point. This encourages the alignment to follow the sides of a valley as it parallels a river, or to follow a low ridge across an open area, without forcing it to climb when crossing a narrow ridge.

Local defaults zone

1. For the general procedure, see Create a zone and choose the Local Default option.

2. The Layer field is set to Local defaults as the type of zone but it can be placed in any existing layer by clicking on the drop down list.

3. Select a local default for one or more of the following:

• • Bridge type

  • Tunnel type

  • Wall type

  • Geology type

  • Geometry type

If you select this option, then:

• Unspecified - The local default zone will not affect the parameter. For example: Selecting Unspecified for Geometry type will cause the zone to use the default geometry type. If the default is changed to another geometry type, the geometry of this zone will change to match it.

• Global default - The parameter within the zone will be the same as the global default (marked with a blue tick)

• New - Another dialog opens to enable you to define a new type for that parameter.

Note: What you select will replace the default for that item. If you only want to change one attribute (e.g. only change the bridge type) set the values for all of the other parameters as Unspecified. The default type will be used for these. You do not need to re-specify every type in a Local Defaults zone if the parameters you want to use are already specified in the default type.

Example

If the global default geometry is 4-lane 100 km/h and there are two other geometries, 4‑lane 80km/h and 4-lane 60 km/h, then:

• Zone A is a local default zone that specifies 4-lane 60 km/h. 

• Zone B is another local default zone, contained in zone A.

If Zone B specifies Global default or 4-lane 100km/h, the initial effect is the same. But if you change the Global default to 4-lane 80 km/h, the results change:

• In the first instance, the geometry in the interior of zone B would be 4-lane 80 km/h (which is now the Global default).

• In the second instance, the geometry in the interior of zone B would be 4-lane 100 km/h (because you specified the geometry by name).

Earthwork Limits zone

You can also limit the height or depth of earthworks so that the scars of cuts or fills on a landscape are limited.

To create an earthworks Limits zone:

1. On the Insert tab click the Create Zone button. Choose Earthworks Limits from the drop-down menu. The Earthwork Limits dialog appears.

• If an embankment exceeds these limits, the software inserts a retaining wall.

• If the centerline exceeds these limits, the software inserts a dry bridge in fill or tunnel in cut. When Quantm Desktop inserts a dry bridge, it extends it either side of the bridge where the alignment attains the bridge abutment limit. Transitions between cuts and tunnels are treated in the same way.

  • In the above dialog, if the earthwork embankments go beyond 30m the system will revert to retaining walls. If the centreline of the alignment goes beyond 30m fill, the system will insert a dry bridge.

  • Bridge abutment limits must not exceed the fill limit, and the tunnel portal limit must not exceed the maximum cut depth. In this instance the system will extend the length of the bridge in both directions until the bridge height actually commences at 10m (the Bridge Abutment value), then extend further with the abutment slope defined in the Bridge Tab of the Cost Parameters dialog. If the centerline of the alignment goes beyond 40m in cut, the system will insert a tunnel. However, the system will extend the length of the tunnel until the tunnel entry and exit portal height is at 15m (the Tunnel Entry value).

2. Enter the limits.

3. Click OK.

4. Trace the boundary of the zone in the Plan view, double-click to close the zone.

To edit the zone, see Editing Zones.

Area Cost Zones

Area Cost Zones add a cost value to the construction process for a particular task within the specific region defined. This may include the additional cost for land acquisition or land clearing prior to construction. The specific costs related to the Area Cost activities relate back to the Area costs previously defined in the Cost Parameters dialog box, see Area costs.

Create an Area Cost Zone

1. Select Area Cost Zone from the Create Zone pull-down in the Insert tab.

2. The default Layer Field is Area cost, this can be changed if required. 

3. Choose a Name for the new zone

4. Select a corresponding Area cost type to associate with this Zone.

5. Click OK.

6. Create the zone by clicking on the Plan view to trace the outline of the zone.

7. Double click to close the zone.

Linear Cost Zones

Similar to Area Cost Zones, Linear Cost Zones allow you to define a region where a specific additional linear cost will be required for construction. This may be an additional linear cost for road marking, signage or installing safety berms. The Linear Cost used relates to those previously defined in the Linear tab of the Cost Parameters dialog box, see Linear costs.

Create a Linear Cost Zone

1. From the Insert tab select Create Zone. Select Linear Cost Zone from the drop-down list.

2. The default Layer Field is Area cost, this can be changed if required.

3. Choose a Name for the new zone.

4. Select a corresponding Linear cost type to associate with this Zone.

5. Click OK.

6. Create the zone by clicking on the Plan view to trace the outline of the zone. 

7. Double-click to close the zone.

Global Zones

Global Zones are unique in the sense that they do not require a polygon to define their geographic location, so they do not appear on the study area: Global Zones automatically cover the entire study area. They impact alignments in the same way as the previously mentioned zones, but are truly global, covering the entire DTM. Only one global Crossing zone and one global Earthwork zone can be employed at a time, although multiple Global Area cost and Global Linear cost zones are allowed.

Create a Global Zone

1. In the Insert tab select Create Global Zone.

There are four distinct types of Global Zones that can be created. The process for defining the properties of Global Zones is the same as normal local zones, except that you do not need to trace a polygon boundary to define the zone. Global Zones have a different icon to normal zones in the Layer View as defined below:

a. Global Crossing Zone see Crossing zones and Water zone.

b. Global Earthworks Limits Zone see Earthwork Limits zone.

c. Global Area Cost Zone see Area Cost Zones.

d. Global Linear Cost Zone see Linear Cost Zones.

Delete a zone

Do one of the following:

• Select a Zone, by clicking on the polygon in the Plan view. Right-click and then select Delete. 

• In the Layer view, open the layer containing the zone. Click on the zone name. Right-click the zone object and select Delete.

Note: All objects in a layer need to be deleted in order to delete a layer.

Global zones have no visible boundary. Delete Global zones in the Scenario Explorer (Layer view tab). Right-click the zone and select Delete.

Overlapping zones

When you create different zones that overlap each other, the particular crossing rules at these locations may change. It is important that when zones overlap, you investigate the constraints of each overlapping zone to ensure that the combination of constraints are still valid and that there are no contradictory crossing rules applied. The following is a list of rules which must be addressed when dealing with overlapping zones. These rules apply to the sections of zone intersection (i.e. where the zones in question overlap):

• When Avoid zones overlap, and the zones carry constraints of differing severity, the most severe of the constraints are applied.

• When Crossing zones overlap, the software uses the intersection of their vertical clearances.

• Crossing zone requirements override local or global default requirements. 

• There can be only one geology, geometry, bridge type, tunnel type, and retaining wall type at any point in the study area. If multiple zones impose conflicting conditions at some point, the software selects the type in the zone that has the closest boundary to the east of the point. If boundaries have been correctly drawn, these conflicts should not occur. However, this feature can be used to create islands of differing requirements within a larger zone. This feature enables you to:

• Create a geology zone of type A, surrounded by a geology zone of type B, which is itself surrounded by the default geology, without having to define a “hole” in zone type B in order to accommodate zone type A.

• Create zones that have holes in them, because you can set the inner zone to match the current default type rather than a specific type. If the default is changed to another type, the inner zone will also change.

Edit Zones

The properties of a zone can be edited, providing it has not been used in an alignment optimization. Edit the zones in the Scenario Explorer (Layer view tab), the Properties window or the Plan View.

Scenario Explorer (Editing Zones)

Use the Scenario Explorer (Layer view tab) to

• edit the layer of the zone

• edit the name of the zone

• enable or disable the zone (activity)

• change the color of the zone

• display or hide labels for the zone

• control the visibility of the zone

See Layer View tab.

Properties Window (Editing Zones)

Use the Feature Properties window to:

• edit the nature of the zone

Warning: Editing the Nature of the zone has a major impact on the zone and the properties displayed.

• edit the zones layer

• enable or disable the zone (activity)

• edit the display properties of the zone (the nature of a zone determines its default color)

• edit the position of the zones label

• edit the position of the zones boundary

• edit properties unique to the zones nature including:

• priority of an avoid zone

• geometry type

• crossing type

• structure type

• reference altitude

• clearance

To edit a zone in the Properties window:

1. In the Scenario Explorer select the Layer view tab. Select the zone to edit. Alternatively, select the zone in the Plan view.

2. Click the Feature Properties icon. The Feature Properties window appears. Details displayed depend on the nature of the selected zone.

Tip: When viewing the properties of a selected object, the cells of the table are highlighted either in white or light gray. Only those cells highlighted white can be edited.

Note: The value in the Area field is calculated from the coordinates of boundary vertices, and cannot be edited.

3. Edit the appropriate field.

Plan View (Editing Zones)

After zones have been imported (see Import GIS/CAD data) or created, it is possible to alter their shape by editing the vertices of the objects.

Move a vertex

1. 1. Unlock feature points by clicking the Lock Feature Points point icon. The Lock Feature Points icon will change to an unlocked icon allowing you to manipulate the vertices of objects.

2. Select the zone from the Scenario Explorer (Layer view) or click the object in the Plan view.

3. As you move the cursor over a vertex (highlighted by white squares around the boundary of the zone) the cursor changes to a square with four arrow points north, south, east, and west. Click and hold the vertex that is to be moved. Drag-and-drop the vertex to the required place. In this example, it is moved to the left.

Add a vertex to a zone

1. Select the zone from the Scenario Explorer (Layer view tab) or the Plan view.

2. Press and hold [Ctrl] as you click the boundary where you want to add a vertex. The cursor will change to a square with an arrow above it pointing south.

3. Drag-and-drop the new vertex to where you want it. See To move a vertex.

Note – Objects can only be edited and moved within the plan view once the Lock Feature Points icon is turned off.

Delete a vertex from a zone

1. If objects are locked and cannot be edited, unlock by clicking the Lock Feature Points icon.

2. Select the zone.

3. Press and hold [Ctrl] as you click the vertex that you want to delete. When the cursor is over a vertex it will change to a square with an ‘X’ in the top right corner.

Use the “snap to” feature to make the vertices that define a zone boundary match the vertices of another zone boundary or the vertices of a feature.

Snap to a vertex

• Press and hold [Shift] as you drag-and-drop the vertex. The vertex snaps to the nearest vertex within 16 pixels of the cursor. Any vertex that is more than 16 pixels away has no effect.

In this figure, a vertex is dragged from its original position and snapped to a new location, indicated by the cursor. When you release the mouse button, the two vertices match exactly.

Note: It is possible to snap to any object (or its vertices) within the plan view.

Next topic: Features (object data)