- MacSlope allows an unlimited number of surcharges to be applied to the ground surface of the slope geometry.
- To create a surcharge, click Define Surcharge under the Materials/Loads tab in the tool palette, or select Define Surcharge from the Drawing Menu.
- Select a line on the ground surface using the mouse, then click and drag your cursor above the desired location.
- You will be presented with two blue markers representing the left and right boundaries of the surcharge.
- Click markers for manual input of the location, or slide markers to move location above the selected line. Note that surcharge boundaries do not snap.
- Use the Select/Pan tool to edit the surcharge pressure and inclination angle by right clicking over the surcharge. A constant or linear change in surcharge pressure may be specified.
- By default surcharges are created normal to the selected ground surface line. Surcharges can not be specified parallel to the ground surface line.
- The units to define surcharges are kPa in Metric and psf in Imperial.
- MacSlope sums each surcharge pressure over the width of each slice it passes over and creates a force acting at the top mid point of the slice, at the specified inclination angle.
- Once an analysis is complete, use the Inspector Tool and click over a slice to view the slice forces and verify the surcharge pressure has been modeled as expected.
- Take care specifying surcharges on a submerged ground surface. If the option "Include No Strength Regions in Slice" is enabled for submerged slopes, the surcharge will be applied to the top of a no strength region, which is not physically possible. In this case it is recommended to use the "Apply Hydrostatic Force to Top of Slice" option for submerged slopes.
Using the Select/Pan Tool to edit / delete a surcharge
- Click the Select/Pan Tool in the tool palette, and click once on a surcharge in the drawing to select it. The surcharge will be highlighted to indicate it is selected. Now right click over the selected surcharge and a menu will be presented with the option to edit the surcharge magnitude/angle, or delete the surcharge. Alternatively, a selected surcharge may be removed from the drawing by pressing the delete (⌫) key.