What does the zero balance line represent on a mass diagram?

What does the zero balance line represent on a mass diagram?

• A. Excavation quantity equals embankment requirement
• B. Waste region above zero line
• C. Borrow region below zero line
• D. The maximum point

Answer: (A)

In a mass diagram you track how much earth you cut (excavation) versus how much you need to build up (embankment) along the alignment. The zero balance line is the point where those two quantities are equal, so the net earthwork is zero. That means no material has to be borrowed from outside the project and no waste material needs to be disposed of at that location. If the diagram sits above the zero line, you have more excavation than fill and surplus material must go somewhere or be wasted; if it sits below, you need additional borrow to supply the embankment. So the zero balance line represents excavation quantity equals embankment requirement.

In a mass diagram you track how much earth you cut (excavation) versus how much you need to build up (embankment) along the alignment. The zero balance line is the point where those two quantities are equal, so the net earthwork is zero. That means no material has to be borrowed from outside the project and no waste material needs to be disposed of at that location. If the diagram sits above the zero line, you have more excavation than fill and surplus material must go somewhere or be wasted; if it sits below, you need additional borrow to supply the embankment. So the zero balance line represents excavation quantity equals embankment requirement.