Asphalt Paving

A typical system includes prepared subgrade, granular subbase where required, compacted granular base, one or more asphalt binder courses, and a surface course. Geotextile, geogrid, stabilization, or subdrains can be added by design. Thickness and materials depend on soil, groundwater, frost, traffic repetitions, axle load, and drainage, not one standard parking-lot detail.

The pavement designer uses geotechnical support values, frost conditions, drainage, expected axle loads, traffic repetitions, turning and braking, and design life. Truck courts often require thicker granular and asphalt, stronger binder mixtures, and local concrete at trailer or dock positions. Harrowgate builds the approved section and verifies each layer before it is covered.

Proof rolling applies a controlled load to expose yielding, pumping, rutting, or non-uniform support before granular and asphalt hide the problem. It does not replace density or geotechnical testing. Harrowgate marks unstable zones, removes or stabilizes them as directed, restores grade, and repeats acceptance so the pavement is supported consistently.

The contract controls acceptance. City of Toronto TS 310 lists minimum compaction of 91 percent of maximum relative density for SP 19.0 and SP 25.0 and 92 percent for other listed hot mixes. Field gauges or cores are used as specified, and low-density areas can require removal and replacement.

Paving cannot produce accepted bond and density on frozen, wet, or excessively cold surfaces. The specification sets seasonal and temperature limits. Harrowgate also evaluates haul distance, wind, lift thickness, and mix cooling. Covered loads, uninterrupted delivery, and rollers close to the paver help, but they do not correct an unsuitable base or weather window.

We establish crossfall and longitudinal grade, set catch basins and curbs accurately, protect granular from saturation, and install subdrains where designed. Dense asphalt and sealed joints limit infiltration, while stable shoulders and curb interfaces protect edges. Final survey and water checks identify low points before markings and full site traffic begin.

The asphalt must cool sufficiently to resist rutting, pickup, and steering marks, and all joints, edges, structures, and temporary transitions must be safe. Light vehicles can often return before concentrated truck turning. Harrowgate stages reopening by zone and load, considering lift thickness, temperature, mixture, and any concrete or sealant work tied into the paving.