Mass Haul Diagram
Click the Mass Haul button in the Alignment tab to see the mass haul in profile.
The mass haul diagram is derived from a cumulative plot of cut minus fill. If cut exactly balances fill over the diagram, the accumulated imbalance in the plot also indicates the volume of material being moved past any point and the direction of movement.
A surplus of cut (above the axis) at a point means that you must move the surplus material past that point toward the finish.
A deficit of material (below the axis) at a point means that you must move material toward the start to make up the deficit.
However, mass haul is usually not as simple as the situation described above. One or more of the following factors may apply:
Features, such as an unbridged river, form a barrier that prevents material from being hauled past and divide the alignment into independent sections.
Some cut may be unsuitable for use as fill and must be dumped.
Cut and fill may not balance exactly within the sections.
Dump sites provide locations where unwanted material can be disposed of.
Borrow pits provide locations where extra material can be acquired.
Material may be exported for some external purpose, such as overpass ramps, and provided at no cost. This material must be sourced and transported as part of the overall earthmoving task.
Material may be imported from some external sources and may need to be transported and used, or dumped as part of the overall earthmoving task.
Imbalances between cut and fill on a section are resolved at dump sites and borrow pits, and their location affects the direction that material flows. As a result of these factors, usable and unusable material may move in opposite directions past some points and need to be accounted for separately. For a more detailed explanation of mass haul and the usage of barriers, borrow pits and dump sites, see Earth Moving.
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