7437 Race Road
Pavement Consulting
Hanover, Maryland
Facility Engineering Associates, P.C. (FEA) assisted the owner with the repairs of the building's surrounding parking lot. The project scope included repairs to various asphalt pavement sections, concrete repairs at curbs, gutters, and sidewalks, and implementation of various drainage improvements for surface and subsurface water.
FEA assessed existing conditions at the parking lot, including visual inspection of all pavement and concrete areas and limited investigation of drainage conditions. A previously produced external geotechnical report outlining pavement and soil conditions taken from various boring investigations was referenced during the assessment. The results of the evaluation indicated that the majority of the pavement area was in fair condition and still had several years of useful life left. However, various areas of pavement were observed to be in poor condition with alligator cracking or surface rutting and needed repairs. The deterioration was determined to be primarily caused by base failure due to insufficiently thick asphalt sections, soft soils, and excessive subsurface water.
The concrete sections were found to be in good condition overall, with several areas of deterioration or damage present. Limited drainage investigation indicated excessive subsurface water seepage through cracks in the pavement, as well as various areas of ponding surface water throughout the parking lot.
FEA developed a repair approach that was intended to repair problematic areas only and seal the remainder of the pavement area to allow for an extended useful life before requiring a full mill and overlay repair. Pavement repairs included full-depth repairs at base failure of the pavement and mill and overlay repairs at rutting in parking spaces. Concrete repairs included replacement of damaged or deteriorated curbs, gutters, sidewalks, and dumpster pad. Drainage improvement included installation of underdrains at various pavement sections to control subsurface water, as well as a trench drain and troughs cut through landscape islands to help control surface runoff. Once these initial repairs were completed, the full pavement area was crack filled and seal coated to seal the pavement area and help increase the useful life of the section.
The pavement repairs were specified to allow for continual use of as much of the parking lot as possible. Careful phasing and continual discussion with the contractor and client allowed for smooth phasing changes and successful road closures that created minimal distress to the building tenants.
The project included several elements that increased the durability of the pavement repairs, and increased the useful life of the pavement. Increased thickness of pavement section to a 10+ inch section Inclusion of geo-textile fabric between the subgrade soil and stone base layers at all repair areas Installation of underdrains within the pavement section to help prevent subsurface water retention Application of crack filler and seal coat to entire pavement surface.