Road Properties

You can set ramp (haul road) parameters in the Road Properties form whenever you add a ramp or edit the properties of a ramp. See: Add Ramp and Edit Properties.

Width

Specify the width of the road.

In order to end up with an accessible road, when you set the width, you may need to take into account the Berm width (if Berm access is enabled as part of your design parameters).

Gradient and Gradient Units

Specify a gradient value and the Gradient Units.

Generate clockwise ramp

If this option is selected, the road will be ramped in a clockwise direction. Clear the check box to ramp in an anti-clockwise direction.

Road Length Calculation

Select an option to determine whether the road length versus gradient will be calculated using either the Inner, Centre, or Outer radius of the road. The length calculation method you choose (and the accuracy of the result) will depend on the characteristics (tightness of curve etc.) of the road.

Select the Custom option to specify an offset value as a factor of the road width. The offset value can only be between 0 and 1 (inclusive of 0 and 1). This parameter is set when adding the road and, once the road has been added to the design, it can only be changed using the Road List or interactively via the Properties pane.

The default calculation method is Inner. If you do not specify a calculation method, the inner radius of the road will be used to calculate the road length.

The selection you make here will determine how the gradient and radius of the switchback (if any) are measured.

Add Flat Section in Next Bench Transition

The ability to generate horizontal parts of a road for a specified distance, including the option of having flat road sections between benches, is a technical requirement in many mines.

Flat section length

If flat sections are required, select the Add Flat Section... option and specify the length of each flat section.

Override Pit Design default parameters

By default, full-width berm access is allowed at both the CREST and the TOE when you add a road to the pit. However, you may choose to override these defaults:

Berm access options

The Toe access width and Crest berm access width options specify how the berms will be accessed from the roads.

Where a berm is accessed by a road you can choose to make the Toe and/or Crest access width the FULL width of the berm, or HALF the width of the berm. You may want to restrict berm access to people, rather than vehicles, for example.

In situations where you do not need to access every berm, you can choose to restrict the access to the Crest or the Toe, or neither, by selecting the ZERO option for one or both to disable berm access to them completely.

If you select CUSTOM for the access width option, you can specify a Fraction value:

Fraction

The Toe access fraction and Crest access fraction options allow you to specify a ratio of the toe/crest access/berm width to apply to the bottom/top of the current road segment.

Taper length

The Toe access taper length and Crest access taper length options can be automatically calculated by leaving the Auto default applied. However, if you want the Toe access or Crest access berms to be tapered at a specific length, enter a value. The length of taper is the distance from the road crossing to the place where the taper starts.

You will receive a warning if the specified taper distance is not appropriate for the pre-defined design parameters. Specifying an inappropriate taper distance may lead to incorrect ramp projections.

Create road centreline

Select this option to display a road centreline.

Road width at Berm Crossing

If Berm access is enabled, choose to use the specified Berm access width to Widen or Shorten the width of the road at the berm crossing.

Switchback Parameters

The following parameters determine how a switchback with a gradient will be built when the road elevation changes from one bench to the next.

Curve Radius

Specify a radius value that will be used to determine the extent and tightness of the curve of the turning area.

Gradient and Gradient Units

Specify a gradient value and the Gradient Units.

Height from start of bench

Specify the height of the switchback from the start of the bench. This parameter characterises the distance from a bench, from which a road making up a segment begins to change direction.

Radius Calculation Line

The radius is measured from a specified (Inner , Centre, Outer, or Custom ) point on the road, taking into account the road width (which is already defined as part of the properties of the road).

• Inner curve radius must be greater than 0

• Outer curve radius must be greater than the road width

• Centre curve radius must be greater than half of the road width

• To measure the radius from a specific point on the road, select the Custom option and specify a value which is a factor of the road width.

Forms

Click the Forms button to select and open a saved form set, or if a form set has been loaded, save the current form set.

OK

Click OK to close the Pit Road form and apply any changes you have made to the form.