Roadworks and Pavement Base

A typical section includes prepared subgrade, optional select subgrade or stabilization, granular subbase, granular base, and one or more asphalt courses, plus subdrains and curb where designed. Exact materials and thicknesses depend on soil, frost, drainage, traffic, and owner standards. Harrowgate builds the issued section and verifies every buried layer.

Under OPSS.MUNI 1010, Granular A is commonly specified as a tighter-graded base close to asphalt, while Granular B types are commonly used as deeper subbase. Their permitted source materials and gradations differ. Harrowgate confirms the specified type and source, prevents cross-contamination, and places each at the designed compacted thickness.

Proof rolling applies a controlled load to reveal yielding, pumping, rutting, or non-uniform support that spot tests may miss. The geotechnical reviewer interprets the response. Harrowgate marks unstable areas, investigates their depth and cause, completes the approved drying, undercut, drainage, or stabilization repair, and repeats review before granular cover.

Surveyed subgrade and top-of-layer elevations provide a broad thickness check, supplemented by depth checks or quantity reconciliation where specified. Harrowgate controls loose spread depth so compaction reaches the target without leaving thin areas. Particular attention goes to crowns, curb lines, utility structures, widened edges, and transitions where grader geometry changes.

Paving should not proceed over saturated, pumping, rutted, frozen, contaminated, or unstable base. Moisture at the surface can also interfere with bond and finishing. Harrowgate restores drainage, dries or replaces affected material, regrades, recompacts, and obtains acceptance. Paving over a temporarily firm crust does not correct a weak layer below.

The trench receives specified embedment and backfill in controlled lifts, with density attention at edges and around structures. Granular and asphalt layers are reconstructed to the road detail, often with saw-cut or stepped limits. Harrowgate removes loose edge material and addresses differential support so the narrow trench does not settle as a visible longitudinal strip.

Provide plan and profile, pavement design, geotechnical report, material and compaction specifications, utility and drainage plans, curb details, traffic staging, proof-rolling and testing criteria, undercut or stabilization allowances, source approvals, restoration limits, survey tolerances, seasonal restrictions, and anticipated construction traffic. Identify whether the road will be municipally assumed.