Spill Width

The Spill Width Parameters option is only applicable in conjunction with the Bench Design option and allows you to customize parameters which are used to calculate the spill width radius of a failed wedge.

When an individual wedge fails, in practice, the result is a volume of failed material which comes to rest at the base of a slope or bench. The failed material typically forms a conical or pyramidal-shaped pile, the extent of which can be estimated by various methods. For example, equations given in Gibson et. al. (2006) can be used to estimate a radius of the failed pile of material. This spill width radius is used in the Bench Design option to determine the bench width necessary to contain the spill (i.e. minimum required bench width). This can be plotted with the Minimum Bench Width Plot in the Bench Design sub-menu in the Statistics menu. See Tutorial 10 and the Bench Design theory document for further information.

To customize spill width parameters, select Spill Width Parameters from the Analysis menu. You can change the following parameters:

• Swelling Factor
• Angle of Repose of Failed Material

These parameters are used in conjunction with equations given in Gibson et. al. (2006) which are used to calculate the spill width radius for a failed wedge, based on:

• wedge volume
• swelling factor
• bench face angle
• angle of repose of failed material