Motor Grader
CSI Division 31, Earthwork
A piece of heavy equipment with a long, adjustable blade mounted between its front and rear axles, used to cut precise, exact final elevations and slopes across a site, the finishing step after rougher equipment has already moved most of the material into place.
Why it matters
A bulldozer gets material roughly into position quickly, but a motor grader is what actually achieves the exact elevations and slopes a civil design calls for. Its long blade and fine-adjustment controls let an operator cut a surface flat and true within a fraction of an inch, which is impossible with equipment built for speed instead of precision.
On a real project
Once a bulldozer has rough-graded a parking lot area, an operator uses a motor grader with GPS machine control to cut the final surface to the exact elevations and slopes the civil drawings specify, so that stormwater drains correctly once paving goes down.
Who this matters most to
A Equipment Operator runs a motor grader during final grading, where the tolerances are tight enough that small errors can cause real drainage problems later.
Where this goes wrong
A motor grader operator cuts a lot's final grade slightly off the design's specified slope, assuming it's close enough. Once paving is complete, water doesn't drain the way the design intended, pooling in a spot that wasn't supposed to collect water at all.