In this example, a road is designed with a large end haul section; the resulting material is used up in a buried culvert crossing of a gully. We want to know how much material is moved and how far.

The middle section on this road has steep side slopes and therefore the cross sections are full bench cut. Full bench construction generates material, when this material is hauled out (instead of being sidecast) it is called end haul.

When excess material is created that cannot be wasted along the road a suitable waste site must be found. In this case the waste material is used to fill a gully and thus make a smoother road as a side benefit.

The fill section is from station 200 to 350. Here is a typical cross section.

As you can see in the figure above showing the profile and mass haul, there is almost no material left over at the end of the construction. The second half of the road (after station 350) was designed to provide reasonable grades and yet to minimize cut (no unnecessary through cuts or daylights). Then, the gully section (station 200 to 350) was re-designed while watching the total mass haul. When the fill required for the gully balanced the end haul material the design was complete.

The Mass Haul graph in the above figure can be read from left to right in the following way:

• From station 0 to 200, a cut of 500 cubic meters is pushed into the start of the gully.
• From station 200 to 1000: 12000 cubic meters is pulled from ahead into the gully.
• From station 1000 to end: the road is roughly balanced (no material moved except sideways).

Fortunately it is possible to move equipment across the gully before the fill has been placed (using a pioneer road). Thus we don’t need to borrow 12000 cubic meters just to get to the area where we start cutting.

The 12000 cubic meter volume is moved somewhere between 300 and 1000 meters (this would be done by truck due to the large distance).

If we break the Mass Haul graph vertically into smaller quantities (2000 cubic meter bands) we can be more specific about how the material is moved.

Turning on the grid options in the Mass Haul Profile sub-window created the above image. (View-Profile Options, select Mass Haul in the Sub-Window list, click the Options button, then finally click the grid button.) The red distance arrows were added later by drawing on the screen capture in the Terrain module (you would probably use a printout in practice).

In this case we can see that 2000 cubic meter chunks are moved various distances (280 meters to 700 meters). If we total these distances we can say that 2000 cubic meters is moved a total of 2960 meters (2.96km).

700
610
550
470
350
280

2960m

The Mass Haul cost is measured as the product of distance and volume (the area under the graph). In this case the cost would be (2.960x2000) = 5920 cubic meter-km. Or if each truck holds 10 cubic meters then one truck must drive 592km loaded and 592km empty. We already know that the total of 12000 cubic meters will take 1200 round trips. 592 truck-km divided by 1200 is an average haul distance of .493km; this is the same as the average of the above distances.

The above analysis assumes that the first cut material (around station 600) is used to fill the end of the gully (around station 350). What if the contractor carried that material to the start of the gully instead?

This reverse construction method produces a different series of haul distances for our 200 cubic meter chunks:

371
395
483
537
565
609

2960m

The total and therefore the cost is identical to the previous scenario:

592 truck-km
1200 round trips (1200 cubic meters at 10 per truck)
493m average haul.

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