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An Analysis of Infrared Asphalt Repair

Technology for the Pittsburgh Public Works

Prepared by Max Goetschel, August 15th

, 2014

It is commonly understood that Pittsburgh’s streets are in need of serious repair. In 2014,

Public Works (PW) Director Mike Gable admitted that 60% of all asphalt streets in Pittsburgh–

over 550 lineal miles– have a rating of “zero”, as in being in the worst condition possible.1

Coupled with the unusual harshness of last winter, the city’s 311 Call Center received over

6,000 pothole complaints in the first three months alone.2

This report recommends that Pittsburgh Public Works explore alternative street

maintenance technologies in order to increase the efficiency and reduce the overhead costs of

asphalt repair jobs. The technology that this report focuses on is infrared asphalt repair systems.

The infrared method can perform seamless patches that can last up to 14 times longer than the

throw-and-roll method currently used today, and has also been shown to cost substantially less

over time. Infrared methods are also highly flexible, and can be used to dramatically improve

repairs on utility cuts, alligator cracks, settlement, longitudinal cracks, bumps, low spots, seam

bonding and manhole cover ramping.

1 Bauder, Bob. "Peduto Bemoans Pittsburgh Potholes, Says Most Complaints Addressed." TribLIVE.com. Pittbsurgh Tribune

Review, 2 Apr. 2014. Web. 08 Aug. 2014. 2 Balingit, Moriah. "Pothole Complaint s Top 6,100 in Pittsburgh." Post-gazette.com. Pittsburgh Post-Gazette, 2 Apr. 2014.

Web. 08 Aug. 2014.

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Contents

Overview of Current System......................................................................................................................... 1

Infrared Asphalt Repair Technology ............................................................................................................. 1

Method ...................................................................................................................................................... 1

Pros ........................................................................................................................................................... 2

Cons .......................................................................................................................................................... 4

Findings from Other Cities & Counties ........................................................................................................ 5

East Lansing, MI: Cutting Costs on Asphalt Purchases ............................................................................ 5

Columbus, OH: Battling Winter Potholes with Infrared ........................................................................... 5

Tallahassee, FL: “Flawless” Utility Cut Repairs ...................................................................................... 6

Bartow County, GA: Less Trucks, Less Workers ..................................................................................... 6

Fall River, MA: Hot-Mix Repairs all Year Round ................................................................................... 6

Policy Recommendations .............................................................................................................................. 7

Conclusion .................................................................................................................................................... 7

Appendix ....................................................................................................................................................... 9

Step-by-Step Process ................................................................................................................................ 9

Local Infrared Repair Laws .................................................................................................................... 11

Point Pleasant Beach, NJ .................................................................................................................... 11

Bloomingdale, NJ ............................................................................................................................... 12

Greenville County, SC ........................................................................................................................ 12

Randolph, ME .................................................................................................................................... 13

1

Overview of Current System

Pittsburgh’s Public Works (PPW) Street Maintenance Division maintains 866 lanes miles

of asphalt streets.3 This year, city council added $1.2 million worth of diverted funds to street

resurfacing.4 While this increase in funding was made to compensate for this winter’s unusually

vicious weather, a small portion of this fund could also be used to explore alternative pothole

repair methods, in order to increase the overall efficiency of our street repair methods as well as

save the city time and money in the long run.

This report assesses the costs and benefits of adding infrared asphalt technology to our

street maintenance division. Infrared was chosen because of its recent surge in popularity among

municipalities in New Jersey, Michigan, and Ohio: states that have climates similar to our own.

Other methods– such as UPM cold patch or green asphalt– were not included in this report, due

to their prohibitive costs and failure to address the current needs of Pittsburgh.

PPW uses the throw-and-roll system as its primary method for repairing potholes. This

method is the oldest and most popular form of pothole repair jobs because it’s fast, easy, and

requires little technology. The process involves cleaning the pothole of water and debris, pouring

hot-mix or cold-mix asphalt into the hole, and compacting the newly placed material with a

roller. The benefits behind throw-and-roll is the short amount of time it takes to complete the job,

as well as the low amount of training needed to perform the patch. The costs, however, are steep:

cold-mix throw-and-roll patches typically only last 3 months, and must be re-patched later in the

year5. Even hot-mix throw-and-roll patches. Using hot-mix asphalt makes more permanent

repairs than cold-mix, but can also lead to permanent patch failure if the process is not correctly

sealed.6 7 8

Infrared Asphalt Repair Technology

Method

The infrared method consists of two main components: an infrared reclaimer and a

pavement heater. The reclaimer is essentially a portable heater that keeps the hot-mix asphalt at a

workable temperature (between 250-350F). The pavement heater is capable of heating the

3 The entire Operations Department also maintains 90 lane miles of concrete streets, 80 lane miles of brick and block stone

streets, 22 lineal miles of City steps, 44,000 street lighting fixtures, 850,000 street signs, 9,272 lots owned by the city, 195 park

facilities & various green spaces, 330 outdoor courts, 128 sports fields, and 129 play areas. 4 City Council Resolution 2014-0365. Pittsburgh City Council Resolutions. 2014. Pittsburgh. Municipal Archives.

5 Wilson, T. P., and A. R. Romine. Materials and Procedures for Repair of Potholes in Asphalt-Surfaced Pavements. Tech. no.

FHWA-RD-99-168. McLean: Federal Highway Administration, 1999. Print. 6 Kubanek, Kathrin. POTHOLE: Final Report. Rep. no. 832700. 5th ed. Vol. 10. N.p.: ERA-NET ROAD, 2013. Print. 7 Ipavec,, Aleksander. Study of Existing Standards, Techniques, Materials and Experience with Them on the European Market.

Rep. no. 832700. Vol. 3. N.p.: ROAD ERA NET, 2012. Print. 8 Nazzal, Munir D., Ph.D., P.E., Sang-Soo Kim, Ph.D., P.E., and Ala R. Abbas, Ph.D., P.E. Evaluation of Winter Pothole

Patching Methods. Rep. no. FHWA/OH-2014/2. N.p.: Ohio Department of Transportation, 2014. Print.

2

existing pavement surface, within and around the area to be patched, to a workable temperature

close to 320F without burning or oxidizing it.

Once the area needing repairs is heated to the appropriate temperature, the area is raked

for higher permeability. Then, the virgin hot-mix asphalt is removed from the reclaimer and

placed into the pothole area, easily blending in with the existing asphalt material and allowing

for a seamless patch that doesn’t allow water to leak in, leading to rapid deterioration of the

repair and permanent patch failure. Figure 1 illustrates the typical design for a trailer-mounted

infrared asphalt repair system.

Figure 1: General Set-Up of a Tow-Behind Combination Infrared Machine

Source: Evaluation of Winter Pothole Patching Methods, Ohio University & ODOT Report

The newly applied asphalt is then luted to form a level cap over the damaged area. Once

that asphalt is in place, a roller must press the area down to form a level cap, starting with the

seams and working its way in. No loud machinery is required, which allows repairs to be

conducted at any time of day without disturbing local residences.9

Infrared can also be used to remove excess asphalt, smooth existing patches, and re-seam

a previous patch job without having to cut into anything. An infrared machine essentially

removes the need for a saw for any kind of job, and uses far less asphalt and labor hours in the

process.

Pros

One of the main causes of patch failure when using the throw and roll and spray injection

methods is due to an inadequate bonding between the patching material and the existing colder

pavement material surrounding the pothole. The temperature difference can result in the

separation of the two materials, which in turn creates a point of entry for debris and water to

9 A detailed explanation of this entire process is in the appendix of this report, and was written by the Ohio Department of

Transportation in partnership with University of Ohio & University of Akron.

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penetrate and may ultimately lead to the failure of the patch. 10

Infrared solves this problem by

heating the existing material to a comparable temperature, rejuvenating the old pavement and

fusing it to the new asphalt. That new asphalt can contain high proportions of used asphalt,

which can substantially reduce new asphalt purchases. This feature is why infrared repair is one

of the most environmentally friendly methods of asphalt repair in the field.

The infrared method is also known to be highly flexible: after talking with ten different

street supervisors and road directors from across the country, this report found that infrared

machines are also being used in utility cuts, settlement, cracks, bumps, low/high spots, potholes,

seam bonding and manhole cover ramping.11

No milling is required when conducting a repair.

Infrared asphalt repair is so effective at utility cuts that this report found six different

municipalities and counties with laws that require every utility cut to be repaired using infrared

technology.12

The University of Ohio partnered with the Ohio Department of Transportation (ODOT)

to conduct a comprehensive analysis of the infrared method.13

Their report found that the

infrared patches had much higher quality ratings than those installed using either the throw-and-

roll or spray injection methods, and are expected to survive up to 14 times longer. 14

Figure 2: Overall Rating with Time for Each Patching Method

Source: Evaluation of Winter Pothole Patching Methods, Ohio University & ODOT Report

10 Munir, Kim, & Abbas ibid. 11 For an expansion on these usages, consult the Findings section. 12 For a list of specific infrared utility cut laws, consult the Appendix section. 13 To request a copy of this report, email maxgoetschel21@msn.com 14 Munir, Kim, & Abbas ibid., 83

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The study also conducted a survey of private companies and municipal governments

who’ve purchased an infrared machine, and over 90% of the survey respondents said their

machine had higher longevity and was more cost-effective than existing pothole repair

methods.15

16

The report concludes that while infrared does cost more than the throw-and-roll method

in the initial 12 months, infrared becomes more cost-effective afterwards due to the long-lasting

repair job, which makes up for the cost of re-doing a patch later down the road.17

The method is

also labor saving: only two workers are required to complete each job. It has also been proven to

be highly effective at conducting longitudinal joint repairs.18

Cons

Infrared repairs are limited to the months in which hot-mix asphalt is in local production.

It may be possible to ship in hot mix from other regions, but shipping costs may be prohibitive.

(although this report found many Public Works who stockpile hot-mix asphalt in the fall, in order

to avoid using the temporary and highly-priced cold-mix asphalt). Infrared also takes longer than

throw-and-roll and spray injection methods, as the heating process typically lasts 5-10 minutes.

Infrared rays can only penetrate 2.5 inches below the surface of asphalt; therefore, infrared

machines cannot be used as a substitute for a full asphalt replacement (PPW’s cold-patch

recycling method is far more efficient for repairing entire stretches of road).

Sometimes when the existing asphalt of a repair site is too old (15-20 years since

creation), infrared heating can cause the brittle asphalt to crack. Those jobs can only be

permanently repaired by either total street reclamation or the semi-permanent method (a.k.a. cut

and saw).

Summary of Pros and Cons

Pros Cons

Requires only two laborers per patch team 5-10 minutes slower than existing methods

Extremely versatile (can be used for utility

cuts, settlement, cracks, bumps, low/high

spots, potholes, seam bonding, manhole cover

ramping, etc.)

Cannot penetrate farther than 2.5 inches below

surface point of asphalt

Lasts 14 times longer than throw-and-roll

methods

Not as effective for older asphalt (+15 years

since initial laying)

Seamless cracks Requires hot-mix asphalt

Low carbon footprint

Easy to use and to teach to existing workers

15 Note: This analysis did not include the cost of car damage that occurs when patch jobs fail, which would add more to the total

cost of using the throw-and-roll method. 16 Munir, Kim, & Abbas ibid., 29 17 Munir, Kim, & Abbas ibid., 78 18 Huang, Baoshan, Ph.D., P.E., and Xiang Shu, Ph.D. Evaluation of Longitudinal Joints of HMA Pavements in Tennessee. Rep.

no. RES 1304. Knoxville: Tennessee Department of Transportation, 2010. Print.

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Substantially reduces amount of asphalt needed

per permanent repair

Highly recommended by other cities/counties

No milling or loud equipment required

Can also be used for longitudinal joint repair

Findings from Other Cities & Counties

East Lansing, MI: Cutting Costs on Asphalt Purchases

Over the years the price of cold patch in Michigan has steady increased from $60 per ton

to around $110 per ton. East Lancing’s Public Works could not afford this increase, so it decided

to look into asphalt saving techniques. Since infrared technology can mix previously used asphalt

in with the virgin asphalt inside the reclaimer, the method requires less asphalt per patch.

Luke Reynolds of Asphalt Solutions met with Homer Allen, Streets Supervisor for the

City. Reynolds did three demonstrations (a utility cut repair, an alligator crack repair, and an

existing patch job that was too high) with a KASI infrared machine. Allen remembered that

“those three jobs that would normally have used ten tons of cold patch cost us only two tons of

hot-mix. Now, it hasn’t been a year just yet, but I can tell you that after five-six months these

cuts are looking just as good as our normal method, while using eight tons less than you

normally would. And he only used three people for the whole job.”19

East Lancing PW has recently purchased a KASI infrared machine and is planning to use

it this coming winter.

Columbus, OH: Battling Winter Potholes with Infrared

After the previously mentioned ODOT/University of Ohio report was finished, the

infrared machine (Kasi Minutemen, a trailer-operated infrared device) was passed onto the

District 12 region (Greater Cleveland) of Ohio. District 1 uses the machine for year-round

highway pothole patches, doing repairs in the winter months by stockpiling 32 tons of hot-mix

asphalt in the fall. ODOT Highway Management Administrator Butch Huebner oversees the

operations of the infrared machine, and has positive remarks about the method and its practice.

“We’re very happy with our little machine. It’s very easy to teach to your workers, it can be used

large areas that need surface repairs, and it works well around castings.”

Huebner also noted the increased savings associated with using infrared. “Our old method

was spray injection, and although it was a bit quicker, the materials would cost a lot more.”20

19 Homer Allen, Phone Interview. August 8th, 2014. 20 Butch Heuber, Phone Interview. August 6th, 2014.

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Tallahassee, FL: “Flawless” Utility Cut Repairs

In the city of Tallahassee, between 250 – 400 utility cuts are done each month. Most of

these cuts are repaired by the utility companies themselves. If a utility company ever does a poor

job and leaves a crack or a bad edge, the city has to follow up and re-patch the cut themselves.

The old method of fixing these patch failures was to bring in more asphalt and redo the

job in its entirety. After purchasing an infrared machine, now Tallahassee Public Works can

simply heat up the surface and get a compactor to reroll the faults in question. Tallahassee Street

Supervisor Thomas J. Lewis noted that “[Infrared’s are] amazing with utility cuts. What we do is

check all the regular utility cuts, and if we see problems, we bring in the infrared and reseal it.

No tear up, no extra asphalt, no jackhammers necessary. No problem.”21

This saves the

Tallahassee Public Works time and money when it comes to coordinating repair efforts with

private utility companies.

Bartow County, GA: Less Trucks, Less Workers

Bartow County did not have a problem with pothole failures. Their operation struggled

with the number of labor hours devoted to each pothole repair. To repair a series of potholes, one

team would saw and cut a pothole out, and then move onto the next one while a team before

them would shovel and press the asphalt into the freshly cut hole. As Randy Gray, Road Director

for Bartow County explains, “even though the pothole was repaired and stayed in place, it took

several vehicles and lots of employees to perform the duties.”

To cut down on the man hours needed per pothole repair, Bartow decided to purchase an

infrared machine. Randy Gray continues: “The infrared truck allows us to perform basically the

same duties with one unit and [fewer] employees, thus saving us time and money.” Gray also

mentioned the efficiency of infrared machines in adjusting the height of pushed up or rutting

areas near intersections, in which sections of asphalt bulge above the normal street level. Now,

they simply “heat up and cut off the high areas, and then re-compact it to repair for an over

lay.”22

Fall River, MA: Hot-Mix Repairs all Year Round

In Massachusetts, cold-mix asphalt costs $20 more per ton than hot-mix asphalt, and is

ubiquitously known as a temporary repair. To the Public Works of Fall River, it made no sense

to purchase any cold patch. They decided to stockpile large quantities of hot-mix in the fall in

order to make permanent repairs year-round, and bought an infrared machine to make sure each

patch could last as long as possible.

21 Thomas J. Lewis, Phone Interview. August 8th, 2014. 22 Randy Gray. Email Interview. August 12th, 2014

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The results were substantial: Public Works Director Kenneth Pacheco said that after

using infrared patching, the demand for road reclamation decreased by 50%. Pothole complaints

also fell significantly after the winter months. He went on to say, “I only have one infrared

machine and a hot mix box, but I could definitely use another machine. The only thing really

stopping me is man power.” He did, however, express some concern with productivity. “If we’re

on schedule, then we use infrared every time we make a pothole repair because it saves us down

the road. But, if we’re behind schedule, we sometimes have to switch to our old throw-and-roll

methods– because it’s a quicker patch job– in order to keep up.”23

He also pointed out that in the city code of Fall River, every utility cut that is done must

be repaired with infrared. “It’s the best method out there.” He concluded.

Policy Recommendations

There are two Infrared manufactures from which to consider purchasing an infrared

machine from: KM International and Kasi Infrared. These two companies were determined by

price comparisons, reviews, quantitative reports, popularity, and anecdotal evidence from

different Public Works supervisors across the country. Both companies sell hatchback infrared

machines, which can be attached to any sort of vehicle equipped with a 2x4 tow attachment.

This report recommends contacting to do a free demonstration for the street supervisors,

administrators, and laborers of the street maintenance division of the PPW. If they are impressed,

then they should consider purchasing a trailer-attached machine for a one-year trial period. After

the trial period is completed, Pittsburgh’s PW should make a decision on whether to keep using

the machine, expand the fleet, or sell it in a public auction.

If a machine is bought, a one-day training session must be given to all future operators of

the device. Infrared asphalt repair is contingent on following proper procedures and storing the

materials correctly. The machine should also combine the companies procedural

recommendations with the recommendations given by the Ohio University/ODOT joint report,

which goes into lengthy detail about the best possible practices (as determined by extensive

experimentation) when using an infrared machine.

Conclusion

The PPW is pressed for street maintenance funds, and having to re-repair patch jobs is

costly in the long run. Infrared technology creates long-lasting patches without substantially

cutting into the PPW budget. A typical tow-behind infrared machine costs between $18,000-

$70,000, and its’ operating costs are similar to our current methods. As we start to make more

permanent pothole patches to our streets, the initial capital investment will pay for itself (this is

without even accounting for the other asphalt repairs that the technology excels at such as utility

23 Kenneth Pacheco. Phone Interview. August 13th, 2014

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cuts and crocodile cracks). Improving the overall efficiency of our street maintenance program

can go a long way towards fixing Pittsburgh’s damaged roads.

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Appendix

Step-by-Step Process

Figure 2

(Continued)

10

Source: Evaluation of Winter Pothole Patching Methods, Ohio University & ODOT Report

Notes on Step 3: Wait approximately 15 minutes for pavement to become 280 degree hot mix

again. Time varies by ambient temperature. Can be used in temperatures as cold as 10

degrees below zero. System emits true infrared rays, heating asphalt without burning or

oxidizing.

Notes on Step 10: Let restored area cool before opening up to traffic.

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Local Infrared Repair Laws

Point Pleasant Beach, NJ

Ordinance 2012-26 InfraRed Patch Road Restoration Requirement

Adopted: June 26, 2012

AN ORDINANCE OF THE BOROUGH OF POINT PLEASANT BEACH,

COUNTY OF OCEAN, STATE OF NEW JERSEY, AMENDING AND SUPPLEMENTING

SECTION 14-1 OF THE BOROUGH CODE, ENTITLED “EXCAVATION AND

CONSTRUCTION IN PUBLIC STREETS” TO REQUIRE INFRARED PATCH DURING

ROAD RESTORATION.

BE IT ORDAINED by the Mayor and Council of the Borough of Point Pleasant Beach, County

of Ocean and State of New Jersey as follows:

SECTION 1: Chapter XIV of the Borough Code, entitled “Streets and Sidewalks” shall be

amended and supplemented at Section 14-1, entitled “Excavation and Construction in Public

Streets,” by deleting Section 14-1.11 in its entirety and replacing same with the following:

“14-1.11 Restoration of Surface.

The surface of all streets shall be restored by the applicant after 30 days settlement time or

appropriate mechanical compaction using six inches of Dense Graded Aggregate, four inches of

Hot Mix Asphalt (HMA) 19M64 Base Course and two inches of Hot Mix Asphalt (HMA)

9.5M64 Surface Course, as set forth in New Jersey Department of Transportation Standard

Specifications for Road and Bridge Construction. At the time the final surface restoration is

made the entire trench area plus one foot border of existing pavement to remain shall be heated

with an infrared heater and then the entire surface rolled to form a seamless repair over the

excavation area. The bond posted for compliance shall be released only after acceptance and

approval by the Borough Engineer of the municipality of the work completed and acceptance and

approval of the County of Ocean and State of New Jersey when appropriate.”

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Bloomingdale, NJ

ORDINANCE 14-2013

OF THE GOVERNING BODY

OF THE BOROUGH OF BLOOMINGALE

AN ORDINANCE OF THE BOROUGH OF BLOOMINGDALE, IN THE

COUNTY OF PASSAIC AND STATE OF NEW JERSEY, THE CODE OF THE

BOROUGH OF BLOOMINGDALE BY AMENDING CHAPTER XX,

“STREETS AND SIDEWALKS,” ARTICLE II, “STREETS,” CHAPTER 20-11,

“STREET OPENINGS AND EXCAVATIONS,” SECTION 20-11.16,

“RESTORATION,” TO REQUIRE INFRARED PAVEMENT RESTORATION

FOR ALL ROADS OPENED WITHIN FIVE YEARS OF PAVING

…

f. Any road that has been paved in the last five years shall be restored with infrared

pavement restoration for areas up to 50 square feet, as approved by the Borough Engineer. Areas

over 50 square feet shall be restored by milling and paving from curb-to-curb. The final scope

and depth shall be determined by the Borough Engineer.

Greenville County, SC

Section 18-66. Fee Schedule

The initial permit fee for all longitudinal and transverse installations within the road rights-of-

way shall

be required in the following amounts:

…

(c) Newly Paved Roads

If it becomes necessary to cut any road, which has been resurfaced within three years of the

permit application date, a fee of $335.00 shall apply for the first year, $235.00 for the second and

$135.00 for the third. Restoration of the cut shall entail compaction reports from a 3rd party geo-

technical firm confirming 95% compaction. The restoration patch shall be done using an infrared

paving process or an overlay of the entire roadway at the discretion of the County Engineer.

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Randolph, ME

…

K. ‘Infrared Process’ shall mean the process of reheating an existing asphalt surface, adding

more Hot Mix Asphalt if needed, raking and rolling the material to remove the joint in the

asphalt surface

F. When an area to be repaved exceeds one hundred (100) square yards, an additional 12” of

pavement shall be milled at a depth of the required thickness of the surface pavement

surrounding the repair area. Resurfacing shall be accomplished using self-propelled paving

equipment complying with the latest MDOT and Town specifications. The Town may require the

surface of the new pavement to be infrared treated when completing permanent repairs. The

infrared or other approved process if required shall be performed not less than six (6) months or

more than twelve (12) months from the date of resurfacing.