References

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percent, along with a corresponding

increase in penetration values.

It became evident that the rejuvenator

could work in Travis County. The

use of a rejuvenator was of most interest

as product cost was one-third to

one-half the cost of the closest alternate,

which would be a wear course seal.

Using that alternative, the condition of

several days ahead of the application,

and to-date there has been a 95 percent

success rate in clearing the streets

of vehicles prior to application.

The subdivision streets are vacuum-

swept in 24 to 48 hours after application.

A bonus is that because the

rejuvenator does not contain asphalt,

coal tar base or gilsonite, any tracking

is kept to a minimum with little or no

residential complaints.

Factual examples of core data testing

are shown in the accompanying table.

Travis County and Pavement

Restoration, Inc. have led by example

and are showing other Texas municipal

agencies their method of extending

pavement life at a low cost.

 

the F mix—along with the many miles

of inventory—would have deeply impacted

the county budget (wear course

seals being chip or Type 1 and 2 slurry

are placed on more severely distressed

pavements in the county).

PROGRAM COMMENCES

Starting in 2006, Ward and Travis

County went forward with a program

of rejuvenating 35 to 50 miles per year.

The project was let to bid with a tight

set of specifications, as the county

knew what it wanted to achieve.

Any remedial hot pour rubber

crackfilling work was to be done four

to eight weeks ahead of the application.

In 2008 the program was in its

third year. Work is performed during

June to August, when ambient

temperatures are 65 to 85 deg F (18 to

30 deg C).

The rejuvenating emulsion is applied

at application rates of 0.07 to

0.08 gallons per square yard, diluted

2 parts product to 1 part water (0.32 to

0.36 liters/sq. meter). A washed concrete

sand is used as a blotter at a rate

of 1 to 2 lbs. per sq. yard (0.45 to 0.90

kg/sq. meter). The sand blots any rejuvenator

that has not fully penetrated

the surface. The rejuvenating emulsion

breaks or cures in about 40 minutes.

Typically two to three streets are

done at the same time, half of the

road per application. Traffic control

is maintained by the contractor. Door

knockers are used to advise residents

On Travis County, Tex., pavements, the top

three-eights inch of each core was removed

for testing. The asphalt was extracted and

recovered as prescribed by California Test

Method 365 (CTM 365). Viscosities were

determined on the recovered asphalt binder

using a sliding plate microviscometer (CTM

348). Penetrations were calculated from a

nomograph.