Describe the cut/fill balance method using cross-section area data.

Describe the cut/fill balance method using cross-section area data.

• A. Compute volumes of cut and fill from each cross-section and sum; balance equals total cut minus total fill.
• B. Compare cut volumes to fill volumes and take the larger as the balance.
• C. Use only the largest cross-section to estimate balance.
• D. Balance is defined as total fill minus total cut.

Answer: (A)

Cut/fill balance with cross-section area data means turning the ground profile along the alignment into a series of cross-sectional areas of material to be removed (cut) or added (fill). For each cross-section you determine how much must be cut where the existing ground is above the design grade and how much must be filled where it is below grade. These cross-section areas are then converted to volumes—typically by using the spacing between sections and applying a trapezoidal or prismoidal rule to approximate the volume between adjacent sections. After you have the volumes for every section, you sum all the cut volumes and sum all the fill volumes. The balance is the net difference: total cut minus total fill. A positive result means there’s surplus material to export or place elsewhere; a negative result means additional material must be imported or borrowed to reach the grade.

Cut/fill balance with cross-section area data means turning the ground profile along the alignment into a series of cross-sectional areas of material to be removed (cut) or added (fill). For each cross-section you determine how much must be cut where the existing ground is above the design grade and how much must be filled where it is below grade. These cross-section areas are then converted to volumes—typically by using the spacing between sections and applying a trapezoidal or prismoidal rule to approximate the volume between adjacent sections. After you have the volumes for every section, you sum all the cut volumes and sum all the fill volumes. The balance is the net difference: total cut minus total fill. A positive result means there’s surplus material to export or place elsewhere; a negative result means additional material must be imported or borrowed to reach the grade.