Asphalt Maintenance – Investing Versus Cost

Below is an example of the 30 year cost of having a proper maintenance program vs. a reactive approach:

Properly Maintained Parking Lot

  • New cost of Asphalt lot- year 1- 30,000 sq ft parking lot- $ 75,000
  • Proper 2 coat squeegee/spray application after year 2- $3,800  (oil spots treated/ minimal cracks fixed)
  • Proper 2 coat squeegee/spray application every 4 years after- $4,000 /application x 7 applications= $28,000

Total cost for proper 30 year maintenance plan- $31,800

Same parking lot not properly invested in a true maintenance program but reactively having work done:

  • Sealed with spray only application after year 5- $2,700  (add $1,500 for hot crack repair)= $4,200
  • Year 10- Replace asphalt driveway and deteriorated oil spots, some alligator cracks (5,000 sq ft)= $12,500  and sealed with spray application- $2,700=  $15,200
  • Year 18- add 2” overlay on entire parking lot= $45,000
  • Year 25- sealed with spray application- $2,700
  • Year 30- sealed with spray application- $3,000

Total cost of reactive asphalt maintenance- $70,100

30 Year cost difference of $38,300 more money spent by not having a pro-active asphalt plan.  These number are real, contact a local asphalt contractor to verify.

Alligator Cracking

Alligator cracking is a load associated structural failure. The failure can be due to weakness in the surface, base or sub grade; a surface or base that is too thin; poor drainage or the combination of all three. It often starts in the wheel path as longitudinal cracking and ends up as alligator cracking after severe distress.

FIX: Because a structural failure is taking place the only possible solution to alligatoring is to perform a full-depth patch.

Raveling 

(very porous asphalt)

Raveling is the on-going separation of aggregate particles in a pavement from the surface downward or from the edges inward. Usually, the fine aggregate wears away first and then leaves little “pock marks” on the pavement surface. As the erosion continues, larger and larger particles are broken free and the pavement soon has the rough and jagged appearance typical of surface erosion.

FIX: Apply a thin hot-mix overlay. Other solutions could include: sand seal, chip seal, slurry seal or micro-surfacing.

Block Cracking

Block cracks look like large interconnected rectangles (roughly). Block cracking is not load-associated, but generally caused by shrinkage of the asphalt pavement due to an inability of asphalt binder to expand and contract with temperature cycles. This can be because the mix was mixed and placed too dry; Fine aggregate mix with low penetration asphalt & absorptive aggregates; poor choice of asphalt binder in the mix design; or aging dried out asphalt.

FIX: Less severe cracks measuring 1/2 inch or less can be sealed to prevent moisture from entering into the sub grade. More severe cracks should be fixed by removing the cracked pavement layer and replacing it with an overlay.