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summarized in Tables 2.11 and 2.12, respectively. These ranges Costs
are based on information reported by various sources, repre-
senting a variety of conditions, and using different perfor- Although treatment costs do not affect treatment performance,
mance measures. As such, these reported ranges may be based certain cost considerations are inevitably a part of the treat-
as much (or more) on perception instead of on well-designed, ment selection process. The cost of each treatment depends on
quantitative, experimental analyses. features such as the size and location of the project, severity and
Additional evaluation of treatment performance was per- quantity of distresses, and the quality of a treatment's con-
formed in this study, taking into consideration factors such stituent materials. It also depends on the type and amount of
as traffic volume, climatic/environmental conditions, and surface preparation work and the degree of traffic control
existing pavement conditions. This evaluation, which is doc- required to accompany the treatment.
umented in the project report, resulted in refinements to Allowing roads to deteriorate over time costs significantly
some of the performance estimates listed above. The refined more than maintaining roads in good condition. The cost for
estimates are presented later in this document as part of the reconstruction of a 25-year-old roadway can be more than
treatment selection process. three times what it would have cost to "maintain" it using a
Table 2.11. Expected Performance of Preservation
Treatments Applied to HMA-Surfaced Pavements
Expected Performance
Treatment Pavement Life
Treatment Life (yr) Extension (yr)
Crack filling 24 NA
Crack sealing 38 25
Slurry seal 35 45
Microsurfacing
Single course 36 35
Double course 47 46
Chip seal
Single course 37 56
Double course 510 810
Ultra-thin bonded wearing course 712 NA
Thin HMA overlay
Dense graded 512 NA
Open graded (OGFC) 612 NA
Gap graded (SMA) NAa NA
Cold milling and thin HMA overlay 512 NA
Ultra-thin HMA overlay 48 NA
Hot in-place recycling
Surface recycle and thin HMA overlay 610b NA
Remixing and thin HMA overlay 715c NA
Repaving 615 NA
Cold in-place recycling and thin HMA overlay Between 68 and 715d NA
Profile milling 25 NA
Ultra-thin whitetopping NA NA
Sources: Peshkin et al. 1999; Lamptey et al. 2005; Peshkin and Hoerner 2005; Dunn and Cross 2001;
Newcomb 2009; Cuelho et al. 2006; Okpala et al. 1999; Caltrans 2008; NDOR 2002.
Note: NA = Not available.
a Current indications are that SMA overlays perform the same or slightly better than dense-graded overlays.
b Range based on reported performance of surface recycle and subsequent surface treatment.
c Range based on reported performance of remixing and subsequent HMA overlay of unspecified thickness.
d Range based on reported performance of CIR and subsequent surface treatment (6 to 8 years) and CIR and
subsequent HMA overlay of unspecified thickness (7 to 15 years).
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Table 2.12. Expected Performance of Preservation exclusive of traffic control costs and any associated surface
Treatments Applied to PCC-Surfaced Pavements preparation costs.
Expected Performance For HMA-surfaced roadways, the costs of crack sealing and
Treatment Pavement Life
filling are relatively low compared with other preservation
Treatment Life (yr) Extension (yr) techniques; however, the other preservation treatments can
effectively address a broad range of conditions, so a direct
Concrete joint resealing 28 56 comparison of costs is not appropriate. Reported cost esti-
Concrete crack sealing 47 NA mates for slurry seals are approximately $0.75 to $1.00/yd2,
Diamond grinding 815 NA depending on the size of the project, materials used, and the
rate of application. Costs for microsurfacing vary consider-
Diamond grooving 1015 NA
ably, but normally range between $1.50 and $3.00/yd2. While
Partial-depth concrete patching 515 NA
the cost of cold in-place recycling depends on numerous fac-
Full-depth concrete patching 515 NA tors, including depth of milling and the properties of the
Dowel bar retrofitting 1015 NA existing pavement, average costs are approximately $1.25 to
Ultra-thin bonded wearing course 610 NA $3.00/yd2. The cost of recycling can be four to six times more
Thin HMA overlay 610 NA
than the cost of chip seals and can be higher than the cost of
constructing a thin HMA overlay.
Sources: Peshkin et al. 1999; Smith et al. 2008; Peshkin et al. 2007; Caltrans
2008; NDOR 2002.
For PCC-surfaced roadways, the cost for full-depth repairs
Note: NA = Not available. on jointed pavements varies significantly. Typical costs in the
year 2000 ranged from $75 to $150/yd2. Diamond grinding
costs were, on average, between $1.75 and $5.50/yd2. Costs
sequence of preservation treatments over the same 25 years. fluctuate depending on many factors, including the existing
Hence, cost is a critical component in the selection of appro- pavement's aggregate quality and PCC mix properties, average
priate treatments at any traffic level. depth of removal, and smoothness requirements. SHAs have
Tables 2.13 and 2.14 list the typical unit-cost ranges and found that the cost of diamond grinding is generally lower than
corresponding relative costs of preservation treatments the cost of an HMA overlay, and such cost-effectiveness makes
applied to HMA- and PCC-surfaced roadways, respectively. diamond grinding an appealing alternative for many concrete
The costs represent the in-place costs of the treatments, rehabilitation projects.
Table 2.13. Estimated Treatment Costs for Preservation
Treatments on HMA-Surfaced Pavements
Treatment Relative Cost ($ to $$$$) Estimated Unit Cost
Crack filling $ $0.10 to $1.20/ft
Crack sealing $ $0.75 to $1.50/ft
Slurry seal $$ $0.75 to $1.00/yd2
Microsurfacing (single-course) $$ $1.50 to $3.00/yd2
Chip seal (single-course) $$ (conventional) $1.50 to $2.00/yd2 (conventional)
$$$ (polymer modified) $2.00 to $4.00/yd2 (polymer modified)
Ultra-thin bonded wearing course $$$ $4.00 to $6.00/yd2
Thin HMA overlay (dense graded) $$$ $3.00 to $6.00/yd2
Cold milling and thin HMA overlay $$$ $5.00 to $10.00/yd2
Ultra-thin HMA overlay $$ $2.00 to $3.00/yd2
Hot in-place recycling (excluding
thin HMA overlay for surface
recycle and remixing types) $$/$$$ $2.00 to $7.00/yd2
Cold in-place recycling (excluding
thin HMA overlay) $$ $1.25 to $3.00/yd2
Profile milling $ $0.35 to $0.75/yd2
Ultra-thin whitetopping $$$$ $15.00 to $25.00/yd2
Note: $ = low cost; $$ = moderate cost; $$$ = high cost; $$$$ = very high cost.
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Table 2.14. Estimated Treatment Costs Although these estimated costs depend on the condition
for Preservation Treatments on of a particular roadway, as well as local contracting and con-
PCC-Surfaced Pavements struction costs and materials and techniques used, the direct
Relative Cost cost of the treatment is often the easiest to determine. Gen-
Treatment ($ to $$$$) Estimated Unit Cost erally, this is available as historical cost data or estimated
based on previous bids. In considering pavement condition,
Joint resealing $ $1.00 to $2.50/ft
a pavement with more cracks will take more money per mile
Crack sealing $ $0.75 to $2.00/ft to seal or patch, and rougher pavements may take a higher
Diamond grinding $$ $1.75 to $5.50/yd2 quantity of emulsion for a chip seal. However, treatments
Diamond grooving $$ $1.25 to $3.00/yd2 such as milling and overlay or recycling are relatively inde-
pendent of existing pavement condition, provided that the
Partial-depth patching $$/$$$ $75 to $150/yd2
(patched area) pavement is in sufficiently good shape to be a candidate for
(equivalent $2.25 to the treatment.
$4.50/yd2, based on The cost of eventual rehabilitation should account for how
3% surface area
patched) often the preservation process will be repeated and what
needs to be performed. For example, a chip seal at the end of
Full-depth patching $$/$$$ $75 to $150/yd2
(patched area) its life span can generally be covered with another chip seal.
(equivalent $2.25 to However, if the project was an overlay in an urban area with
$4.50/yd2, based on curb and gutter, milling might be necessary to maintain pro-
3% surface area
patched)
file before another overlay can be added.
Although less than a quarter of the survey respondents
Dowel bar retrofitting $$$ $25 to $35/bar (equiva-
lent $3.75 to
reported that they account for user costs when selecting a
$5.25/yd2, based on preservation treatment for high-traffic-volume roadways,
6 bars per 12-ft these costs can represent a significant portion of the total
crack/joint and
cost and should be taken into account. Detailed guidance
crack/joint retrofits
every 30 ft) in computing certain forms of these costs is provided in
Chapter 3.
Ultra-thin bonded $$$ $4.00 to $6.00/yd2
wearing course
Thin HMA overlay $$$ $3.00 to $6.00/yd2
Note: $ = low cost; $$ = moderate cost; $$$ = high cost; $$$$ = very high cost.
