What is mass excavationin construction?

Mass excavation is the open cut that lowers the whole site or pad, dug with large equipment at high production. Structural excavation is the confined digging for footings, grade beams, pits, and elevator shafts after the mass cut is done, usually slower and several times more expensive per cubic yard. Specs and bid forms often separate them so the unit prices reflect the different work, and estimators should never blend them into one rate.

A bank cubic yard (bcy) is soil measured in place, before excavation. Once dug, it swells: common earth at an illustrative 25 percent swell turns 1 bcy into 1.25 loose cubic yards (lcy) in the truck or stockpile. Compact it as fill and it shrinks below its bank volume. Pay quantities for mass excavation are usually bank measure, while truck counts and stockpile sizes run in loose measure.

By comparing two surfaces: the existing grade from the topographic survey and the design subgrade from the grading plan. Earthwork software builds both surfaces and reports the volume between them. By hand, the grid method divides the site into cells, averages cut depth at each cell's corners, and multiplies depth by cell area, while the average end area method works from cross sections. Either way the answer is in bank cubic yards.