KUTC Winter 2001 Newsletter - ku.edukutc/pdffiles/KUTC Winter-01.pdfBecause increasing binder quantity may lead to flushing if conventional binders are used, some form of modi-fication

NewsletterA Local Technical Assistance Program (LTAP) of The University of Kansas Transportation CenterIn cooperation with Kansas Department of Transportation and Federal Highway Administration

KUTC

An issue dedicated to paving and road maintenance

Winter 2001

Inside:

New asphalt mixguide

MUTCD...Free!

Which Kansas counties are affected

by GASB 34?

Base stabilization

Use of guardrail onlow volume roads

Giving new life to old asphalt

(by recycling it)

Using RAP on lowvolume roads

New Federal focus onasset management

How ‘bout them gravel roads?

KDOT video on concrete pavement

smoothness

Maintaining roads forbicycling safety

Video reviewsUpcoming workshops

Lending library

and more!

Add Some Muscleto Your Chip SealsHow to design a chip seal process thatcan hold up in heavy traffic

. . . by Lisa Harris . . . . . . . . . . . . . . . . . . .

Broken windshields. Noisy roads.Short-lived pavement. These are rea-sons why road managers shy away

from chip-sealing on high-volume roads.But what if these problems could bereduced? Chip-sealing is an economical wayto repel water and extend pavement life, andwith careful attention to the process, itcould be a viable option for high-volume aswell as low-volume roads.

The American Society for Testing andMaterials (ASTM) published a study in1998 describing methods of constructingchip seals on high volume pavements(approx. 30,000 ADT) to reduce or avoidthese problems. This article will outline thestudy’s recommendations for buildingstronger and more cost-effective chip seals.

The study outlines these common problems associated with chip seals on high-volume roads:

● Vehicle and windshield damage, due to: —excess chips—inadequate traffic control—inadequate sweeping

● Short life expectancy, due to:—inadequate binder quantity—substrate pavement too cold—binder too cold

—cool or cold weather immediately after construction—submergence of chips in substrate pavement—loss of binder adhesion or cohesion

● Tire noise and roughness, due to:—large one-sized aggregate

The study looked at a wide variety of possi-ble solutions to the above problems at over20 test sections at four locations inOklahoma, California, and Virginia. Thefollowing methods were tested: single seal,double seal, and “sandwich” seal.

Some strategies worked better than others. Here are the researcher’s recommen-dations based on the results of the tests.

Recommendations for MakingStrong Chip SealsIncrease aggregate embedments. As traffic lev-els increase above 7500 vehicles per day perlane, aggregate embedments should beincreased to prevent aggregate chips frombecoming dislodged.

Add more binder as ADT increases.Because existing design procedures appear tobe inaccurate predictors of binder content,the study recommends that new design pro-cedure be developed that applies a positivecorrection for binder rate as traffic increases

continued on page 2 ➤

fic facilities. These new specificationsshould account for: 1) a requirementfor a job-mix formula for the chip gra-dation, much like those used inasphalt concrete construction; 2) posi-tive traffic control requirements; suchas pilot vehicles, detours, or closingthe road until the next day; 3) positiveequipment calibration requirements;and 4) rigorous quality controlrequirements during construction toassure materials applications rates.

Use double-application seals toreduce noise and increase pavement life.This method, using two applicationsof chips and binder (with the secondapplication of chips being smallerthan the first) results in a denser sur-face than a single application. At oneof the sites, the double chip seal wasnoticeably quieter than correspondingsingle seals using larger aggregate.Minimal vehicle damage on all of theprojects and good performance after5-6 years indicates the feasibility ofthis type of construction.

Watch the weather. In addition tothese specific recommendations, thestudy noted that the use of heated orprecoated chips can help asphaltcement binder adhere to chips incooler weather. Problems caused bycool weather can be reduced byscheduling chip seal jobs earlier in thefall so that temperatures do not dropsharply at night and affect proper set-ting of the binder and adhesion to thesubstrate pavement.

The study summarized in thisarticle is described in greater detail inthe source below. The book FlexiblePavement Rehabilitation andMaintenance can be purchased fromASTM for $58, hard copy. It can beordered online at www.techstreet.com.The book contains eleven comprehen-sive, peer-reviewed papers examiningseveral topics on pavement evaluation,rehabilitation and preservation.

Source: “Design and Construction ofChip Seals for High Traffic Volume,”by Scott Shuler, in Flexible Pavement

Control chip size. The 4.7mm(No. 4) aggregate fraction should belimited to less than 35 percent passingfor 9.5 mm (3/8 inch) and largermaximum size gradations. At one ofthe test sites, high quantities (61 per-cent) of material passing the No. 4sieve became embedded in the emul-sion before the 9.5 mm ships, pre-venting proper embedment of thechips. These 9.5 mm materialsbecame dislodged and contributed toa high incidence of vehicle damage onone particular day at one of the sites.

Avoid steel-wheel rolling. Thistechnique was used at one of the fourtest sites but observations during con-struction and performance indicatethis practice should be avoided, par-ticularly on high-volume roads, dueto lack of compaction and potentialfor crushing.

Use caution with synthetic aggre-gates. Lightweight synthetic aggregateswere tried at some of the sites in anattempt to reduce vehicular damage.At one test site they disintegrated; atanother they held up well.

Use conventional spray nozzles.Variable volume spray nozzles wereused at one of the sites and per-formed well for applying higherbinder quantities between wheel-paths. However, the study cautionsthat the difficulties of machining spe-cial nozzles and positioning them inthe distributor may outweigh thebenefits. Conventional nozzlesworked well at the other sites.

Think twice about sandwich seals.This is a double application of chipsand a single application of binder.This method was only marginally suc-cessful at one of the sites. Althoughthe advantage of using one applicationof binder for a double seal saves timeduring construction, the method isvery sensitive to application rate andmay not be practical for routine use.

Adopt new specifications. Thestudy recommends the developmentof new specifications when planningconstruction of chip seals on high traf-

Page 2 KUTC Newsletter

to 7500 vehicles per day and above.Because increasing binder quantitymay lead to flushing if conventionalbinders are used, some form of modi-fication to stiffen the binder was rec-ommended.

Use pilot cars for traffic control.Traffic control using pilot cars at 25mph to keep traffic on the new chipseal surface was recommended onehour following final rolling. This traf-ficking appeared to benefit the earlyperformance of the seal by improvinginitial embedment.

While slower speeds might bedesirable to reduce damage potentialto the seal and vehicles, this may bedifficult to achieve. At one test sitethe pilot car traveled at 15mph andsome frustrated drivers passed it.

If pilot cars are not feasible, thestudy highly suggests using polymermodified asphalt binder because of itsenhanced adhesive properties.

Control chip application.Application rates should be controlledto achieve a layer one-stone thick tominimize excess chips and maximizeadhesion with the binder. The studydescribes the appearance beforerolling as being somewhat low onaggregate with some holidays on thesurface. (Holidays are where some theunderlying asphalt shows through.) Itis difficult to achieve a one-stonethick application if the aggregate gra-dation contains may size fractions, sothe study suggests using one, or atmost, two sizes of aggregate.

Clean the surface after chip appli-cation. The use of push or vacuumsweepers was recommended. Lightsweeping should be done as soon afterrolling as practical such that the freshseal is not damaged—but so that anyloose or excess chip are removedbefore traffic is allowed on the pave-ment. A second round of light sweep-ing approximately 12 hours later wasalso recommended.

Stronger chip seals,continued from page 1

Winter 2001 Page 3

New Guide for Asphalt Mix Selection

What’s the best type of hot-mix asphalt for a ruralroad with a low traffic

volume? How about for ahigh volume highwaywith heavy truck traf-fic? Road depart-ments and contrac-tors looking forguidance onselecting the rightHMA mix for avariety of trafficand environmental conditions cannow turn to a new handbook— MixType Selection Guide.

The handbook describes severaltypes of mixes including open-graded

friction courses, stone matrix asphalt,and fine-and coarse-graded densemixtures. The handbook also coversgeneral recommendations for surfacepreparation, recommended sublayers

for different mix types, typesof pavement drainage, andrehabilitation techniques.It is a joint publication of

the Federal HighwayAdministration and the

National PavementAssociation.

The handbook is scheduled to bepublished by mid-February. To obtaina free copy, call Joe Garcia at FHWAat (202) 366-2226 or e-mail him at:[email protected]. ■

AtchisonBarberBourbonBrownButlerCherokeeClarkClayCowlyCrawfordDickinsonDoniphan

DouglasEdwardsEllisEllsworthFinneyFordGearyGoveGrayGreeleyGreenwoodHamilton

HarperHarveyHaskellJacksonJewellJohnsonKearnyKingmanLaneLeavenworthLoganLyon

MarionMcPhersonMiamiMontgomeryMorrisMortonNessOsagePawneeRawlinsRiceRussell

ScottSedgwickSewardShawneeSmithSumnerThomasTregoWallaceWichitaWyandotte ■

59 Kansas Counties tobe Affected by GASB 34

In a report from the Kansas Division of Accounts & Reports dated January24, 2001, the following counties were identified as preparing GAAP finan-cial reports. These counties will need to revise their reporting procedures in

accordance with GASB 34. We are printing this list so these counties mightnetwork with their peers if they have questions about how to handle infrastruc-ture reporting and other issues of concern.

For more information on GASB 34, refer to Summer and Fall 2000 issuesof the KUTC Newsletter.

GASB has recently issued an “Exposure Draft” recommending changes toGASB 34. It can be viewed on their website at www.gasb.org. Paragraphs 8 and32-34 clarify the “Modified Approach for Reporting Infrastructure,” i.e, assetmanagement.

✍

The KUTC would like toacknowledge the loss of alongtime friend to Kansas

local road agencies—Vern Everhart.Vern passed away in Topeka onJanuary 20, 2001.

Vern was a civil engineer with theKansas DOT for 30 years. He wasassistant bureau chief/technical man-agement for the Bureau of LocalProjects. He was also very active in hiscommunity and church.

Vern was a good friend to theKUTC, providing advice and assis-tance to us on numerous occasions.

We extend heartfelt condolencesto Vern’s family and colleagues. Hewill be deeply missed. ■

In Memorium

MUTCD, Free!

Before you rush out and buy acopy of the new MillenniumEdition of the MUTCD—wait!

You may be getting one for free.KDOT’s Bureau of Local Projects

will be using federal 402 safety fundsto purchase a copy of the revisedMUTCD, printed copy, for all 105Kansas counties and for Kansas citieswith active local projects. They will beshipped out as soon as they arereceived by the Bureau. FHWA is esti-mating delivery in August.

Local Projects will also supply aloose-leaf binder for holding andorganizing the different sections.

For more information, call JoelBreakstone at (785) 296-3861. ■

Rehabilitation and Maintenance, edit-ed by Prithvi S. Kandhal and MaryStroup-Gardiner, ASTM, 1998, pp.97-118. ■

Lisa Harris is editor of the KUTCNewsletter.

KUTC NewsletterPage 4

Recipe for a Stable Subgrade. . . by Robert L. Parsons, P. E. . . . . .

Use of stabilization agents toimprove the performance ofsubgrade materials has

become a widely accepted method forimproving the reliability and reducingthe cost of pavement sections. Signifi-cant and even dramatic improvementsin workability, uniformity, strength,and shrink/swell control are achievablewith the proper use of these products.

The most commonly used stabi-lizers are lime, fly ash, and portlandcement. Related products, such ascement kiln dust, are available in someareas. A number of liquid stabilizationagents are also available, although as agroup they have a more limited recordof performance. The most appropriatematerial varies with the project and isa function of the objective of treat-ment, soil type, cost, and availability.

Soil treatment objectivesSubgrade soils may be treated withone or more different objectives inmind. The most basic is to dry outwet soils. Dry lime, fly ash, andcement will all accomplish this func-tion by consuming the excess mois-ture in reactions of hydration.

Another objective is soil modifi-cation. Modification refers to chemi-cal changes in treated clay soils thatcan lower the plasticity, improveworkability, and greatly reduceshrink/swell problems.

The Kansas Department ofTransportation (KDOT) currentlyrequires modification of subgradesoils beneath both bituminous andPCC pavements, with the primarygoal of eliminating shrink/swell prob-lems and also to prepare a workingtable for subsequent construction.Some strength increase will also typi-cally be achieved with modification.

A third potential objective of

treatment is stabilization. Stabilizedmaterials share the characteristics ofmodified soils and also show a signifi-cant strength gain over the unstabi-lized material. For example, anincrease in compressive strength of atleast 50 psi is a common mix designcriteria (1). Equivalent pavement

designs with reduced pavement thick-nesses can be achieved if the sub-grades are stabilized. For example, innew subdivisions, Johnson Countypermits an eight inch asphalt pave-ment to be replaced with a combina-tion of six inches of fly ash stabilizedsubgrade and six inches of asphalt.

Stabilization agentsLime. Lime is probably the most

widely used soil improvement agentand is the dominant soil modificationagent used by KDOT east of US-81.The term “lime” may be used to referto several specific materials. These aredry calcium oxide (CaO) or quick-lime, dry hydrated lime (CaOH), andlime slurry. Lime slurry is normallyprepared by mixing quicklime withwater, although hydrated lime mayalso be used.

Lime improves clay soils in three

ways. At lower concentrations the cal-cium in the lime modifies the soil byreplacing the cations normally presenton the surfaces of the clay particles.This exchange of cations improvesworkability, and greatly reduces thetendency of the soil to draw in waterand swell when water is available.Lime is also an effective stabilizationagent in many clay soils. Lime willreact with the clay particles, forming agel that acts as a cementing agent—greatly increasing strength. Dry limealso serves as an effective drying agentfor wet soils.

Fly ash. Class C (self-cementing)fly ash is a waste product produced bythe burning of sub-bituminous coal.It contains some calcium and poz-zolanic materials as a part of the ashand acts as a cementing agent. Fly ashwill not generally reduce the plasticityas much as lime, and while it hasbeen shown to reduce swelling in soilswith significant swelling potential,there have been conflicting results onits effectiveness when compared withlime. Fly ash is an effective dryingagent and can significantly improvesoil strength. It is a common methodof stabilization used in JohnsonCounty for reconstruction projects.

Portland cement. Portland cementis also used for both modification and stabilization. Well graded sandyand gravelly materials with 10-35 per-cent fines are considered the mostfavorable for treatment. These soilsmay require as little as 3 percentcement by weight for stabilization (2).Soils with little or no fines may besuccessfully treated, although theymay require slightly more cement.Clay soils may be treated with cementbut will require a significantly greater proportion of cement to achieve stabi-lization. Portland cement and fly ashare the primary soil modification

continued on page 14 ➤

Winter 2001 Page 5

New Study Establishes Guidelines for When toInstall Guardrail on Low Volume Roads

. . . by Lisa Harris . . . . . . . . . . . . . .

Roadway managers can readilyfind guidance for determiningwhere to install guardrail on

heavily-traveled roads. But, until now,practical guidelines have not beenavailable for installing guardrail on lowvolume roads (LVR).

A recent K-TRAN* study address-es that need. Entitled Use of Guardrailon Low-Volume Roads According toSafety and Cost Effectiveness, its statedpurpose “was to bring together the lat-est research and models on roadsidehazard reduction, site specific KansasLVR conditions, accident cost, localgovernment finances, and practicalcommon sense.” It provides guidancefor installing guardrail adjacent toembankments, utility poles, and threetypes of culverts on low volume roads.

A technical committee providedexpertise for the study. Its membersincluded three Kansas county engi-neers: Norm Bowers, Dean Chesnut,and Richard Teaford; and four repre-sentatives from KDOT: Vern Everhart,Ron Seitz, Jerry Preim, and GeleneSavage. Researchers at Kansas StateUniversity conducted the research.

The study resulted in generalguidelines for guardrail installation. Itincludes a group of easy-to-use tablesto help LVR personnel identify safe,cost-effective solutions, or a practicalbalance between least cost and “zerorisk.” The tables show different condi-tions (offset, ADTs, etc.) for each ofthe types of obstacles. An example ofthe information contained in one of

these tables is shown above.The study’s general findings are

listed below, by type of obstacle. Notethat the term “justifiable” means eco-nomically justifiable in this study. Theresearchers acknowledge that otherconsiderations beyond cost-effective-ness may be important.

● Reinforced concrete box (RCB)culvert with straight wings—Based onthe total life cycle cost analysis,guardrail was justifiable for speeds of90 km/h, ADTs of 300 or higher andculvert end height of 2.4 meters.Guardrail was not justifiable if the cul-vert’s lateral offset from the nearestdriving lane was two or more meters.

● RCB culvert with flared wings—The study results indicated that,under all conditions, guardrail wasnot justifiable if the culvert’s lateraloffset from the edge of the nearestdriving lane was more than threemeters. For some other conditions,guardrail was justifiable.

● Reinforced concrete pipe (RCP)culvert with pipe/headwall—Guardrailwas not justifiable if the ADT was less

than 100. Guardrail was justifiable forsome other conditions.

● Utility poles—Guardrail was jus-tifiable for speeds of 90 km/h, ADTsof 400 and lateral offset of 0.0 m and0.3 m.

● Embankments—Guardrail was not economically justifiable foreither 1:4 or 1:3 (vertical: horizontal)relatively-smooth foreslopes, regard-less of the design speed and ADT. For1:3 rough foreslopes, ADT of 400,speed of 90 km/h and height of fill offour or more meters, installation ofthe guardrail was justifiable. Guardrailwas justifiable on most 1:2 foreslopeswith smooth or rough conditions.

Forty percent of accidents on lowvolume roads, nationwide, are run-off-the-road incidents. The researchershope that the guidelines in this studywill assist LVR managers in prevent-ing some of these kinds of accidents.

This report can be downloadedfrom the TRIS Online Website at:www.bts.gov/NTL/data/778822.pdfOr call Bill Jacobs at KDOT for apaper copy at (785) 291-3847. ■

*K-TRAN is a cooperative transporta-tion research program betweenKDOT, Kansas State University andthe University of Kansas.

Obstacle Type: CULVERT, Flared wings, ADT 400, OFFSET 1.0 M

TOTAL COST IN ANNUAL WORTH$ �shaded� cells indicate guardrail is recommended

Speed Cost of Culvert End Height in Meters(km/h) Guardrail 1.0 1.2 1.8 2.4

50 $655 $112 $178 $298 $44360 $681 $196 $290 $456 $65970 $806 $328 $445 $654 $98980 $895 $579 $628 $880 $1,27690 $1,060 $780 $838 $1,241 $1,696

Note: Guardrail is recommended when its annual worth for collision protectionunder the conditions shown is greater than the cost of the guardrail itself.

KUTC NewsletterPage 6

Giving New Life to Old Asphalt

. . . by Kathryn Jensen . . . . . . . . . . . .

In this “green” age, there isincreased awareness about theimportance of conserving

resources. During the last two decades,asphalt has become a major player inthe recycling realm. This article willoutline different methods of asphaltrecycling and types of pavement dis-tresses for which they are appropriate.

There are several ways to recycleasphalt into a new pavement surface.The choice of method depends on thecondition of the road needing repairand how long the area can be reason-ably closed to traffic.

Hot Recycling. This is a goodchoice for rehabilitating pavement thathas been patched or shows cracking(from loads or not), general uneveness,depressions or heaving. In hot recy-cling RAP is combined with newaggregate and an asphalt cement orrecycling agent to produce hot mixasphalt (HMA). Both batch and drumtype hot mix plants are used to pro-duce recycled mix. The RAP is general-ly obtained by pavement milling with arotary drum cold milling machine orfrom a ripping/crushing operation.The mix placement and compactionequipment and procedures are thesame as for regular HMA.

The ratio or blend of RAP to newaggregate will vary, dependent on the

recycled mix properties desired andthe type of hot mix plant. New tech-nology using microwave heating mayallow the use of up to 100 percentRAP without the occurrence of blue

smoke problems.Hot In-Place Recycling. This is

useful for surface defects and deforma-tion (raveling, washboarding, shallowrutting), some types of cracking, and

KDOT—A Leader in Asphalt Recycling

Asphalt recycling is no stranger to the Kansas Department ofTransportation. Its first cold recycling project was in 1977; the first hot

recycling project a year later. Both projects were done on US-56 betweenLarned and Kinsley, cities in Pawnee and Edwards Counties. KDOT experi-mented with different additives and methods in various test sections. Theprocess took about three months. Since then, this stretch of road has suc-ceeded in withstanding traffic and the elements. It has been overlaid twicein the 20+ years since the project was completed.

KDOT now uses asphalt recycling for many of its pavement restorationprojects. Between 30 and 40 projects are slated to occur this year. “We’redoing as much or more [asphalt recycling] as any other state, proportionalto number of miles,” said Rodney Maag, KDOT field engineer. “We docold recycling, hot recycling, and hot in-place recycling,” he said. “We basi-cally do every method out there.”

One advantage to cold methods for deep restoration is that the projectsare completed on-site and are drive-able within a few hours of doing thework. Hot projects take longer to cure and often require the milled RAP tobe transported to a hot-mix plant and back, as part of the process.

Hot in-place recycling is completed on the roadway. (In this process,the top inch of the road is heated and scarified. An additive is mixed withthe RAP and the mixture is relaid and compacted.) To make these projectsmore efficient, contractors have been using three or four heaters to heat thepavement. The last heater scarifies the existing roadway.

“That way they can go longer distances in a given amount of time thanif they used fewer machines,” said Maag. “This cuts down on the amount oftime flaggers are needed.” Maag said that increasing the number ofmachines is not required by KDOT, but the contractors who work this waysay that it saves their companies money.

Recycling processes have remained essentially the same over the years,with one exception: fly ash is now added to make the asphalt stronger ratherthan using straight emulsion. KDOT is currently testing another additive: aemulsion and lime slurry combination.

Maag said that KDOT considers asphalt recycling for most projectsbecause it may be more cost effective than laying all new material. “You’reusing the same material you already paid for,” he said. On several Superpaveprojects each year the contractor is given the choice of using RAP.

For more information on KDOT’s asphalt recycling projects, callRodney Maag at (785) 296-3711.

Phot

o by

Ste

ve C

ross

Winter 2001 Page 7

general unevenness. Hot in-place recy-cling is performed on-site, in place,with the existing pavement typicallyprocessed to a depth of 3/4 to 1-1/2inches. The deteriorated asphalt pave-ment is heated and softened to allowit to be scarified or hot rotary mixedto a specific depth. As required, newhot mix material and/or rejuvinatingagent or other liquid additive is addedto the reclaimed material.

Hot in-place recycling is per-formed as a single or two pass opera-tion. With a single pass the restoredexisting pavement material is com-bined with new/virgin material. Fortwo passes, the restored material isrecompacted and the application of anew wearing course then follows aftera prescribed interval or delay.

Cold In-Place Recycling. Thismethod is appropriate for deep rut-ting, all kinds of cracking, and torehabilitate maintenance patching.It reuses existing pavement materials,and all work is completed while onthe pavement being recycled.Additional transportation of materialsis normally not required except forthe additive being used. The depth oftreatment is typically around fourinches. In some cases virgin aggregatemay be added to the recycled materialto change/improve the RAP charac-teristics. Asphalt emulsion, emulsionwith lime, fly ash or asphalt rejuve-nating agents may also be used.

Cold in-place recycling involvespulverizing the existing pavement, siz-ing the RAP, incorporating an additiveand placing and compacting the recy-cled mix. A recycling train may beused that includes a large cold millingmachine pulling a screening and crush-ing unit followed by a mixing device.The mix is deposited in a windrow forplacement and compaction.

Full Depth Reclamation. Thismethod is useful on roads with deeprutting, all types of cracking, patches,general uneveness, depressions or highspots. With this method all of theasphalt pavement section and a prede-

termined amount of underlying materi-als are treated to produce a stabilizedbase course. Additives are used for animproved base that include importedmaterials, asphalt emulsions and chem-ical agents such as calcium chloride,portland cement, fly ash and lime.

The full depth process includesfive basic steps: pulverizing, introduc-ing an additive, shaping, compactingand applying a surface or wearingcourse. For some projects, new materi-als are added to the mix for increasingthe road thickness and mix properties.

Whichever method is used,asphalt recycling cuts costs by reusingmaterial and decreasing the amount of

materials to be transported to the jobsite. It has proven to be an excellentmethod of road restoration for stateand local road departments.

Sources: Missouri-Kansas Introduction to

Asphalt Recycling and Reclaiming(Conference Guide), by the KS andMO LTAPs and the ARRA, 1994.

An Overview of Recycling andReclamation Methods for Asphalt PavingRehabilitation, Asphalt Recycling &Reclaiming Association (ARRA).

Kathryn Jensen is a senior in journalismat the University of Kansas.

Using RAP on Low-Volume Roads—One County’s Experience

With a sizeable stockpile ofrecycled asphalt on hand,Goshen County (Wy.)

decided to test their RAP as a surfacematerial for roads. In Fall 1998 theymixed some RAP and asphalt emul-sion with a motorgrader and applied itto over a mile of county roads. Thefollowing year the section was stillholding up, but there were a few prob-lems and room for improvement.

The material was produced andlaid in cold temperatures, making itdifficult to work and compact. Thecrews also encountered problems withblading a non-uniform material andeither the wrong type or amounts ofemulsion. Not having a uniform mixmade it difficult to work—with thelarger chunks dragging under theblade for several feet. Many of the sur-face problems were worked out in thenext season, however, with warmertemperatures and the action of vehicletires under traffic.

Gary Craig, the Goshen County’sroad and bridge superintendent, deter-mined that using a more uniform sizeof RAP would improve processing,

compaction and smoothness. Moreambient heat would soften the RAPand make it easier to mix and place.Craig also sent a sample of RAP toKoch Materials to determine theamount and type of emulsion thatwould work best with that particularkind of RAP.

The next project was undertakenin August, in warmer weather. Tobegin the project, crews checked thebase material, and additional basematerial was brought in, watered andcompacted when needed. Using theirown equipment and crews, theCounty crushed the asphalt just priorto hauling it to the project to avoidany reconsolidation of the RAP stock-pile. Crews crushed the material earlyin the morning when temperatureswere cool. The pile retained residualmoisture throughout the processwhich made placing and mixing easierwhile serving to hold down dust. Thecrushed material was hauled to the jobsite and deposited in a windrow toone side of the roadway.

A CSS-1H tack coat was shipped

continued on page 10 ➤

This article is reprinted with permis-sion from Pavement Preservation, anewsletter of the Foundation forPavement Preservation.

Agrowing federal focus on pre-serving the existing system ofstate, local and national pave-

ments is underscoring today’s newemphasis on preventive pavementmaintenance.

In the 1980s—as the nationentered the post-Interstate era—emphasis began shifting from construc-tion of new pavements to maintenanceof existing pavements. Much of thiswas fueled by the Intermodal SurfaceTransportation Efficiency Act of 1991,which explicitly provided maintenancefunds via its Interstate MaintenanceProgram, and Surface TransportationProgram (STP) funds which generally

could be used as a state saw fit. Now, an advancing philosophy of

“asset management ”—adapted fromthe corporate world—is providingnew momentum and excitement forpavement preservation, and it’s beingspearheaded at the federal level by theOffice of Asset Management, createdin February 1999.

“Pavement preservation is at thecore of all future highway programs,”said Madeleine S. Bloom, director,Office of Asset Management, FederalHighway Administration. “Much, ifnot most, of tomorrow’s infrastructureis already built. Now our challenge isto preserve and manage what wealready have. Our focus is on thepreservation of our highway assets,and the great importance of thispreservation on the performance ofour national highway system.”

Bloom spoke at Inroads 2000, aconference conducted by Foundationfor Pavement Preservation (FP 2) charter association members—theInternational Slurry SurfacingAssociation and the Asphalt EmulsionManufacturers Association.

The concept of asset managementmakes sense when you consider thechange in focus of the highway pro-gram from building new highways onnew thoroughfares, to maintenance ofthe existing infrastructure, Bloomsaid. While railroads were the domi-nant transportation mode up toWorld War II, cars and trucks came tothe forefront soon after.

“We responded by building themagnificent Eisenhower System ofInterstate Highways, which knit our

KUTC NewsletterPage 8

New Federal Focus on Asset ManagementEmphasizes Preventative Pavement Maintenance

“Pavement preservation is at the core of all future highway programs...” —Madeline Bloom, director, Office of Asset Management, FHWA.

Will this new federal focus affect local agencies?

We at the KUTC have heard some concern expressed about the newfederal focus on asset management. There’s a fear that local agencies

may eventually need to adopt asset management (and use GAAP financialreports) in order to receive federal funds for local projects. Is this fear war-ranted? We asked Jim Sorenson of FHWA and Larry Emig, bureau chief,KDOT Local Projects (BLP), for their input on this.

Sorenson is senior construction & system preservation engineer withFHWA’s Office of Asset Management in Washington, D.C. He pointed outthat a decade ago (through ISTEA), federal-aid funds were made eligiblefor preventive maintenance on the Interstate system if an activity was cost-effective and extended the highway’s service life. Preventive maintenanceeligibility was extended to all Federal-aid highways by the 1995 NHS Act.

The FHWA has given the states considerable flexibility in spendingfunds for preventative maintenance. This same flexibility is also given toKansas local agencies by the KDOT’s BLP that administers federal funds forlocal road and bridge projects. Emig said: “Our policy is to allow the localagencies to select the scope of their requested projects.” He noted that manyagencies select bridges, because they are expensive projects.

FHWA does not require local agencies to prepare GAAP financialreports or implement asset management, although these practices areencouraged. “Applying the right fix to the right road at the right time willmake our roads perform longer and prove to be much more cost-effective,”Sorenson said.

Emig has not heard of any change in policy from FHWA. He said,“I am not aware of a change... We will see what the FHWA has to offer interms of project types to consider and if we need to revise our process.”

Winter 2001 Page 9

nation together,” she said. “Today, theinterstate system basically is complete,with very small linkages remaining,”Bloom said. “We want to continue tomaintain that marvelous system andimprove it, and perhaps add a fewmiles. But what we are not doing isadding thousands of new miles.”

Throughout the world there hasbeen a shift from constructing newhighway systems to preserving, maxi-mizing and effectively operating whatwe have. “We will manage our invest-ment in the system to optimize itsperformance, and deliver integratedservices to our customers, be theyfreight shippers, commuters ortourists,” Bloom said.

A new look at managementThere is a perceived need by manytransportation professionals for acomprehensive management approachto road systems, given their commonbackground in aging infrastructure,always less-than-adequate budgetsdespite the magnitude of resources,and constrained staff resources. Allthe while the public has increased itsexpectations of what the transporta-tion system can develop, she told thedelegates, implying asset managementmakes that easier.

“There also is a great need fortransportation officials to communi-cate in financial and economic terms,as well as to explain our engineeringconditions,” Bloom said. “By usingrecognized accounting, financial andeconomic principles, we hope thatasset management will enable high-way managers to discuss infrastructurerequirements with budget and policypeople in a common language.”

Bloom defined “asset manage-ment” as a systematic process tomaintain, upgrade and operate physi-cal assets on a cost-effective basis.“We like to say it combines engineer-ing principles with sound businesspractice, and gives us the tools tofacilitate an organized approach todecision-making,” she said. What

makes asset management unique thesedays is its goal to merge differentthemes in road management to a uni-fied, centrally managed approach,Bloom said.

“Asset management, differentfrom, say, bridge management, forexample, emphasizes the entire systemand incorporates a multi-year perspec-tive,” Bloom said. “When you evalu-ate a broad range of resources andassets over a fairly long period oftime, asset management can result insomewhat different decisions than ifeach asset were evaluated in the veryshort term on its own.”

Bloom listed a variety of benefitsto asset management applied to high-way systems: ● determination of the remaining ser-vice life of assets;● optimization of system levelimprovements; and ● analysis of investment strategies,rather than just one project at a time.

“It allows us a common yard stickfor rating a whole range of investmentdecisions,” Bloom said. “From a statetransportation agency perspective,asset management should result inimproved management of the pro-gram, and better use of availablefunding. From a user perspective, thecustomer should benefit by receivingbetter-managed facilities and moreefficient operation of the system.”

Pavement preservation is keyThe 1995 nationwide survey of high-way users determined that pavementcondition—particularly pavementsmoothness—was the most importantcriterion by which user satisfactionwas ranked. “Pavement condition has

been a No.1 concern,” Bloom said.“Also, there was great concern aboutwork zones.”

The politically appealing, butwasteful “worst first” approach toroad maintenance comes into Bloom’scross hairs. “To ensure cost-effective-ness and high quality pavementsrequires a clear identification of ourgoals,”she said. “This may mean aredefinition [of goals], to develop amore strategic, customer-drivenapproach to maintain and preserveexisting highways, rather than simplyfollow the traditional approach of fix-ing the worst first.”

The industry must focus on time-efficient and cost-effective preventivemaintenance techniques, she said.“There’s a great demand for preven-tive maintenance techniques that cancut the need for time-consuming —and traffic disrupting —rehabilita-tion, with all its associated user costs,”Bloom said.

And that falls squarely into thelaps of contractors and material andequipment suppliers, in partnershipwith government agencies. “By apply-ing a range of low-cost preventivemaintenance treatments highwayagencies can start to develop themeans to extend pavement servicelife,” she added. “We ’re partnering[with industry ] to get the word outon a variety of innovations that canhelp preserve pavements, therebymaintaining our enormous invest-ment in the highway infrastructure.”

Bloom can be reached at theOffice of Asset Management at (202)366-0392 or by e-mail [email protected] ■

For a more in-depth look at asset management, download the AssetManagement Primer (PDF file) off the FHWA Office of Asset Manage-ment web site at www.fhwa.dot.gov/infrastructure/asstmgmt/amprimer.pdf.(Or obain a hard copy from FHWA’s Topeka office, (785) 267-7281.)There are many other documents on the office’s web site that will be ofinterest to readers. See them at www. fhwa.dot.gov/infrastructure/asstmgt/.

KUTC NewsletterPage 10

to the County and applied to the exist-ing roadway before the surface materialwas placed. The same tack materialwas applied to the windrow and twomotor graders began the process ofmixing and grading. The distributormade subsequent passes to bring theamount of oil up to five percent.

The RAP was compacted to anaverage thickness of three and a halfinches over a 24 foot wide road. Awater spray system was added to keepthe material from sticking and a fogseal was applied to the finished road,using the same emulsion.

Volumes of traffic for these roadslast summer ranged from 200 to over500 vehicles per day. Most of theroads were left open to traffic duringconstruction. Over 4.5 miles of roads

How ’bout ThemGravel Roads?

Using RAP on low volume roads continued from page 7

. . . by Rose Lichtenberg . . . . . . . . . .

Quality gravel roads are theproduct of well-trained andcapable grader operators

who have access to good equipment.Your operators will have an opportu-nity to further develop their skills byattending a one-day classroom sessionduring late March and early April.Ten sessions have been scheduled:March 27 in El Dorado March 28 in EmporiaMarch 29 in ChanuteApril 3 in Garden CityApril 4 in ColbyApril 5 in HaysApril 6 in HutchinsonApril 10 in SalinaApril 11 in Washington April 12 in Topeka

An old saying goes: “The threemost important elements in maintain-ing a good road are drainage, drainage,drainage.” This course will add anothersaying: “The three most importantways to get good drainage are with aproper profile, proper profile, properprofile.”

For more information, or to reg-ister, call Rose Lichtenberg at785/864-2594, or visit our web site atwww.kutc.ku.edu. You can click onour training calendar and register forthis training on-line. ■

Rose Lichtenberg is training coordinatorfor the Kansas LTAP.

Are yours meeting the standards you set?

were surfaced at a total cost of $1.62per square yard. This amount includesall costs such as use and rental ofequipment, operator wages, hauling,fuel, emulsion, and other materials.This cost would have been less if crewscould have crushed nearer the RAPpile. The county intends to chip sealthese roads this year to extend theexpected life.

Gary Craig is convinced thatusing recycled asphalt is good for hisCounty. If you would like more infor-mation about this project, call Gary at(307) 532-3716.

This article was adapted with per-mission from “Recycled Asphalt inGoshen County, by Gary Craig andSue McFarland, from the Fall 2000issue of the Wyoming T2 Newsletter. ■

Researchers may be on the wayto making calcium magnesiumacetate (CMA) from cheap

feedstocks such as cheese whey.According to a

December 7, 1999 newsrelease from the U.S.Department ofTransportation, theFederal HighwayAdministration, inpartnership with theNew York StateEnergy Research andDevelopment Authority andseveral state highway agencies, fundedthe research that involved fermentingcheese whey to produce acetic acid.When acetic acid reacts with lime itproduces CMA.

Researchers from Ohio StateUniversity’s Department of ChemicalEngineering conducted the research

on behalf of the agencies.CMA has a deicing ability com-

parable to salt but has no significanthealth or environmental concerns. It

is not corrosive to vehicles andnot harmful to concrete, struc-

tural steel, vegetation, fishor other aquatic life.

Cost analysis showsthat CMA made from

cheese whey can be producedat a cost of less than 30 per-cent of the current market

price for commercial CMA,helping to make environmentally-friendly winter highway operationsmore cost effective. ■

Reprinted with permission from theFall 2000 issue of T2 Interchange, anewsletter of the NebraskaTechnology Transfer Center.

What do Deicing and CheeseHave in Common?

Winter 2001 Page 11

KDOT Korner

New Video Gives ConcreteAdvice on Pavement Smoothness

. . . by Stan Whitley. . . . . . . . . . . . . .

Achieving success often comesfrom emulating a leader.That’s why KDOT is being

used as a model for developing ultra-smooth highway pavements.

KDOT implemented smoothnessspecifications for concrete pavement15 years ago. Now a new video,Smoother Roads Playbook, is providinginsight into the successful strategiesthe agency used to achieve smootherconcrete pavements. The smoothness

specifications have resulted in Kansasgaining national recognition for itsinnovative techniques.

The video, produced by FHWAand KDOT, features Kansas pave-ments and construction procedures.John Madden, former NFL coach andwell-known football commentator,provided introductory and closingremarks for the video.

The introduction of pavementsmoothness specifications was “thesingle most important impact on con-crete paving that I have seen in mycareer,” said Mike Lackey, formerKDOT State Transportation

Engineer. Lackey was interviewedextensively for the video. “The bot-tom line is we get our money’s worthbecause we have pavements that lastlonger and require less maintenance.”

Smoothness has been promotedin Kansas not only by the specifica-tions but also through an incentive/disincentive program. The programand smoothness specifications havegenerally been well received by con-tractors because it allows them com-pensation for their extra efforts.

“We don’t think our quality costs

a lot of money,” David Wittwer, pres-ident of Wittwer Paving commentedon the video. “In fact, I’ve told ourpeople that quality doesn’t cost—itpays.”

Eight practices and techniquesuse in Kansas to achieve smoothnesswith Portland cement concrete pave-ment are highlighted on the video.The list includes:

● precise stringline● watching pavement speed and delivery rate● building from the ground up● controlling the concrete head

● striving for mix consistency● minimal hand finishing● using good equipment● motivating the work force

The stringline is the primaryguidance system for most paving con-crete equipment. It must be set pre-cisely and protected from damagebefore paving. It should also bechecked for proper grade and eleva-tion before each paving operation.

The video noted that “the string-line has the greatest potential to affectsmoothness.” Maintaining a consis-tent paving speed and avoiding stop-ping or slowing the paver was alsocited as being very important.

To accomplish this objective,contractors must have an adequatesupply of concrete delivered to thepaving sites and have delivery vehiclesthat can move quickly and easilythrough a site and then back to theconcrete plant.

The impetus for producing thevideo was the results of a 1995 surveyconducted by the FHWA. The surveyfound that smoothness of ride wasone of the most important factors inincreasing public satisfaction with thehighway system.

This article was reprinted withpermission from Translines, October2000 issue, a KDOT publication. ■

Stan Whitley is an InformationalSpecialist at the Kansas Department ofTransportation.

Smoothness has been promoted in Kansas notonly through specifications but also through anincentive/disincentive program. This has generallybeen well received by contractors because it allows compensation for their extra efforts.

KUTC NewsletterPage 12

A Leg Up

Maintenance Ideas for Safer Driving & Bicycling

. . . by Lisa Harris . . . . . . . . . . . . . .

Potholes, accumulated sand,debris, and other roadway haz-ards are dangerous for both

motorists and bicyclists. Some ofthese hazards can cause particularproblems for bicycle riders, especiallynear the right margin of the roadwhere bicyclists tend to ride. Theseareas are generally less well main-tained than the main lanes.

This article will identify commonroadway maintenance issues and waysto make roads safer for bicyclists. It willalso discuss how to be proactive aboutroadway maintenance, so that futureproblems can be anticipated beforethey happen. The recommendations arefrom Implementing Bicycle Improvementsat the Local Level, produced by theBicycle Federation of America and pub-lished by the FHWA in 1998.*

Bicyclists’ concerns can usually beaddressed by slightly modifying cur-rent maintenance procedures, oftenresulting in safer roads for all modes.

Here are some ideas for solu-tions for common mainte-nance problems:

Typical maintenanceconcerns and solutionsPotholes and other surfaceirregularities: Take extra careto make smooth repairs,giving special attention toareas of the roadway usedmore frequently by bicycles.Also, require contractorsand utility companies topatch to a similarly highstandard. Require furthermaintenance if the repairsfail within a year.

Debris (sand, gravel, glass, autoparts, etc.) near the right edge of theroad: Sweep close to the right edge,using vacuum trucks if debris accu-mulates adjacent to curbs. Pay partic-ular attention to locations like under-passes where changes in lighting con-ditions can blind bicyclists to roadwayhazards. Areas where debris washesacross a paved surface should alsoreceive special attention. Eliminatingthe source of the problem is ultimate-ly a more cost-effective solution thanincreased sweeping.

Debris or surface irregularities atcurves and intersections: Curves andintersections are often filled withdebris, especially after the winter sea-son or after flooding or high winds.Be sure to carefully sweep these high-risk areas.

Chip seal gravel: Remove excessgravel as soon as possible and suggestalternate routes as detours.

Ridges or cracks: These should befilled or ground down to reduce thechance of a bicyclist catching a front

wheel and crashing. Pay special atten-tion to ridges or cracks that run paral-lel to the direction of travel. Checkany areas where a merging lane is pro-vided just beyond an intersection.Because traffic must merge left tocontinue traveling straight, bicyclistswill be crossing the joint between themerge lane and through lanes at avery shallow angle.

Encroaching vegetation: Keepgrasses adjacent to roadways mowedso bicyclists can spot potential hazardsahead. Trim vegetation back to allowat least two feet of clearance betweenthe edge of the pavement and the veg-etation, paying special attention toinside curves.

Poorly maintained signs and pave-ment markings: Special bicycle signsmay be subject to frequent theft orvandalism. Be alert to missing or dam-aged signs and replace/repair thempromptly. Pay particular attention tobike route signs at decision points,warning signs at hazard locations, andregulatory signs on popular streets forbicycling. Some pavement markingssuffer more wear and tear than othersand may need special attention, suchas “hot spot” areas for traffic signalloop detectors.

The bigger picture—“ThinkMaintenance”Improving bicycle-related mainte-nance in the long term requires actionon several fronts. First, maintenancepolicies used by all relevant agenciesshould be reviewed and changed ifnecessary. Second, designers should beencouraged to “think maintenance”when they design—low maintenanceshould be the rule rather than theexception. Third, an outreach effort

Surface irregularities that run parallel to travel areparticularly hazardous to bicyclists.

From

Impl

emen

ting

Bicy

cle I

mpr

ovem

ents

at th

e Lo

cal L

evel

, FH

WA.

Winter 2001 Page 13

should be implemented to encouragebicyclists to report maintenance prob-lems and to communicate existingmaintenance problems to bicyclists,especially on bike paths or on popularbicycling routes.

Let’s take a closer look at theseideas:

Identify key players. Work closelywith agencies and personnel responsi-ble for maintaining and designing theinfrastructure. These may includestate and local highway departments,contractors and utility companies.

Review existing policies and prac-tices. Obtain copies of existing sched-ules and policies and determine if anychanges need to be made. Consideradding new standard procedures ortraining to create consistency andawareness among personnel in provid-ing maintenance services to increasesafety for bicyclists.

Review results in the field andsolicit comments from bicyclists. Hopon a bicycle and ride the streets. Thiscan help uncover previously unknownproblems. For instance, an agency mayhave a policy to sweep arterial streetsevery two weeks. But field experiencemay show that certain arterials accu-mulate debris faster due to adjacentland uses. If bicyclists commonly usethese roads, increasing the sweepingfrequency may be justified.

Solicit comments from area bicy-clists as well. They can often pinpointspecific locations and needs. Toobtain such information, send newsreleases to bicycle groups and ask themedia for assistance.

One way to increase useful dia-logue with bicyclists on maintenanceissues is to create an ongoing spotimprovement program. This can helpidentify problems before someone getshurt. Create mail-back postcards fordistribution to local bicycle shops anduser groups. As cards come in, checkthe locations identified and take actionas necessary. Set aside a modest bud-getary allowance to repair maintenanceproblems identified in this program.

Sample objectives—and steps to achievethem—for making roadssafer for bicycles

Maintain roadways to a relatively "hazard free" standard:● by sweeping pavement edges and paved shoulders with sufficient care. ● by patching surfaces as smoothly as possible and by requiring contractorsand utilities to do likewise whenever they dig up and patch a road or trail.● by making sure pavement overlay projects feather the new surface intothe existing one or otherwise do not create new linear joints.● by replacing hazards such as dangerous grates or utility covers as theopportunity arises.● by patching potholes in an expeditious manner.● by routinely cutting back all encroaching vegetation, especially on trailsor popular bike routes.

Encourage bicyclists to report maintenance problems/hazards:● by developing a “bicycle spot improvement” form and distributing copiesthroughout the bicycling community.● by ensuring that returned forms are acted upon in a timely fashion.

Design and build new roadways to reduce the potential for mainte-nance problems in the long term:● by using edge treatments, shoulder surfaces, and access controls thatreduce the potential accumulation of debris.● by using materials and construction techniques that increase the longevi-ty of new surfaces.

Include maintenance costs and clearly spelled-out maintenance pro-cedures in all bicycle facility projects:● by including reasonable estimates of the maintenance costs in the pro-ject’s budget● by establishing clear maintenance responsibilities in advance of construction

Source: Implementing Bicycle Improvements at the Local Level, FHWA publica-tion FHWA-RD-98-105, September 1998.

Recommend appropriate changes andevaluate progress. Identify solutions tomaintenance problems based onreviews and comments, implementthem, and make sure they work effec-tively. A good way to get feedback onimprovements is to ask the bicyclingcommunity for comments on mainte-nance issues on an annual basis.

*FHWA’s Implementing BicycleImprovements at the Local Level is out

of print, but it has been re-issued bythe Institute of Traffic Engineers. It isavailable for $25 for ITE membersand $35 for nonmembers. Call (202)554-8050 for more information. ■

Correction: Our last issue’s article onaudible pedestrian signals had an errorin the amount Topeka pays per inter-section for installation of those signals.The correct amount is $2,800.

KUTC NewsletterPage 14

Calendar

. . . 2001 . . . . .

March 20*Millennium MUTCDATSSA/APWA SatelliteDiscussionin Colby, Salina, Hays,Garden City, Pittsburg,Wichita and Lawrence

March 20-21Bridge Load Testingand Rating Workshopin Kansas City, Mo.Contact MUConference Center at573/882-4349

March 29APWA RoundtableDiscussion in Wichitacall Mike Fraser,785/826-7380

Spring *LTAP SuccessfulSupervision Workshopsessions to be held byrequest of local agency

*LTAP Motor GraderOperator TrainingMarch 27, El DoradoMarch 28, EmporiaMarch 29, ChanuteApril 3, Garden CityApril 4, ColbyApril 5, HaysApril 6, HutchinsonApril 10, SalinaApril 11, WashingtonApril 12, Topeka

April 8-11APWA North AmericanSnow Conferencein Indianapolis, In.Call 816/472-6100

April 10-11Kansas TransportationEngineeringConferencein Manhattan, Ks.Contact Ellen Staufferat Kansas State Univ.Continuing Educationat 785/532-5569.

April 12APWA RoundtableDiscussion in Topekacall Mike Fraser,785/826-7380

April 18-20APWA Mid AmericaConference,in Columbia, Mo.Contact TammyBennett at 785/832-3133

April 21-25National Association ofCounty Engineers(NACE) AnnualMeeting andManagement andTechnical Conference,in Bloomington, Mn.Contact NACE at202/393-5041 or visitwww.naco.org/affils/nace

April 25-26, tentative*NHI Course: AASHTORoadside DesignGuideTopeka, Ks.

May 1-3, tentative*NHI Course:Highways in the RiverEnvironment,in Topeka, Ks.

For information on calendar items indicated witha * or to suggest a topic for a future LTAP work-shop, contact:

Rose LichtenbergKUTC1530 W. 15th Street, Room 2011Lawrence, KS 66045-7609785/864-2594

or visit our Web site at www.kutc.ku.edu

May 8, tentative*NHI Course: WorkZone Traffic Controlfor MaintenanceOperations on RuralRoadsin Hutchinson, Ks.

May 8-9Kansas TransportationSafety Conference,

in Hutchinson, Ks.Call University ofKansas ContinuingEducation, toll free at877/ 404-5823

May 14-16KCHA Spring Meetingin Hays, Ks.Call Ron Karn at 785/863-2211

Stable subgrade,continued from page 4

agents used west of US-81 by KDOT.

Constructing with additivesThe additives discussed above differin construction procedures. TheNational Lime Association recom-mends that soils mixed with lime havea moisture content five percent aboveoptimum during mixing to promotethe reaction of the lime with soil par-ticles (3). It is normally recommendedthat soils be allowed to “mellow” for24 to 48 hours between initial andfinal mixing to permit the lime andwater to break down the clay clods.Fly ash should be mixed dry of opti-mum and compacted as quickly aspossible (within two hours) after mix-ing. Cement treated soil should alsobe compacted as quickly as possibleand have a moisture content nearoptimum or slightly above to accountfor moisture loss from evaporationand hydration (4). Thorough mixingis encouraged for all stabilizationagents to promote a uniform product

and maximize strength gains. Detailedconstruction specifications for eachproduct are available from industryorganizations.

Selecting a stabilizerThe most appropriate stabilizer is afunction of soil type and objective.Lime is normally the most cost effec-tive stabilizer for highly plastic clayswhile cement is more appropriate foruse with coarse grained materials. Flyash is more of an intermediate materi-al. As the optimum application ratecan vary for all stabilizers, it is recom-mended that a mix design be per-formed prior to construction to selectthe stabilizer and determine theappropriate application rate.

More informationMore information on these products,including mix design information andrecommended construction proce-dures, is available from the followingorganizations. For lime, contact theNational Lime Association at (703)243-5463 or www.lime.org. For infor-mation on fly ash, contact the

American Coal Ash Association at(703) 317-2400 or www.acaa-usa.org.For information on cement, contactthe Portland Cement Association at(847) 966-6200 or www.cement.org.

References1. Lime Stabilization: Reactions,Properties, Design, and Construction.Transportation Research Board,National Research Council. State ofthe Art Report #5. 1987.

2. Soil Cement ConstructionHandbook. Portland CementAssociation. Skokie, Illinois. 1995.

3. Lime Stabilization ConstructionManual. National Lime Association,Bulletin 326. Arlington, Virginia,1991.

4. State-of-the-Art Report on SoilCement. American Concrete InstituteCommittee 230. ACI230.1R-90.1990.

Dr. Robert L. Parsons is an assistantprofessor of Civil Engineering at theUniversity of Kansas.

Winter 2001 Page 15

Name Phone number

Position

Agency

Street Address

City State Zip+4

*For all international requests, the requester must pay postage. We will notify you of the postage cost and will send materials after receiving payment.

Check off your selections, fill in the bottom portion, and return this form to:

KUTC Materials Request, 1530 W. 15th St., Room 2011, Lawrence, Kansas 66045or fax to 785/864-3199

Free Resources

Order Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Videotapes . . . . . . . . . . . . . . . .Two videotapes or one-hour’s worth of material per lendingrequest. Two week lending period.

❑ Smoother Roads Playbook24 minutes, by the Kansas DOT and FHWA, 2000. Shows eight practices used in Kansas to achieve smooth-ness with Portland cement concrete pavement. Includes remarks with former NFL football coach John Maddon. For more information, see article on page 11.

❑ Traffic Barriers 46:27 minutes, by FHWA. This tape includes three short programs on traffic barriers: 1) an overview; 2) W-beam guardrails; and 3) end treatments. Shows proper installa-tion and safety guidelines. This is not a new production, but has been added to our lending library.

Publications . . . . . . . . . . . . . . .You are free to keep these unless otherwise noted.

❑ Pavement Preservation: A Road Map for the Future(16 pages) Presents information discussed at a nationalforum in Kansas City, Mo., in October 1998, about pave-ment preservation. Keys areas for action are identified.FHWA, 1999.

❑ Kansas Motor Grader InformationA one-stop course for information on using a motorgrader. Includes two Kansas LTAP publications—Motor Grader Operator Handbook and Motor Grader Tips and Techniques—plus several short articles. Kansas LTAP, 2000.

❑ Improving Highway Safety at Bridges on Local Roads and Streets(35 pages) Provides an excellent general guide to effective, low-cost methods for improving and enhancing bridges and bridge approach safety. LTAP/FHWA, 1998.

Equipment . . . . . . . . . . . . . . . . .Available free—for loan to local highway agencies. Call us at(785) 864-5658 to arrange time period needed for loan. There could be a waiting list for these items.

❑ Jamar Technologies, Inc. (DB-400) Turning Movement Counter BoardA basic model for recording turning movements at inter-sections. The board is is lightweight and comes with its own case.

❑ Jamar Technologies, Inc. (TDC-8) Turning Movement Counter BoardCan be used to do turning movement counts, classification counts, gap studies, stop-delay studies, speed studies, and travel time studies. The board is is lightweight and comes with its own case.

❑ send materials indicated

❑ address correction

❑ add to newsletter mail list

❑ send KUTC 2000 LendingLibrary Catalog

Let us at the KUTC help you find the answers to your transportation-related questions.

KUTC, 1530 W. 15th St. #2011, Lawrence, KS, 66045Call 785/864-5658 (fax 785/864-3199)www.kutc.ku.edu

The Kansas Local Technical Assistance Program (LTAP) is an edu-cational, research and service program of the Kansas UniversityTransportation Center (KUTC), located in the University ofKansas School of Engineering. Its purpose is to provide informa-tion to local and county highway agencies and transportation per-sonnel by translating into understandable terms the latest tech-nologies in the areas of roads, highways and bridges.

The KUTC Newsletter is one of the KUTC’s educational activ-ities. Published quarterly, the newsletter is free to counties, cities,towns, tribal governments, road districts and others with trans-portation responsibilities. Editorial decisions are made by theKUTC. Engineering practices and procedures set forth in thisnewsletter shall be implemented by or under the supervision of alicensed professional engineer in accordance with Kansas statestatutes dealing with the technical professions.

Winter 2001 issue—Copyright 2001 by the KUTC. Allrights reserved. Reproduction of material in this newsletterrequires written permission.

Director . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Joe LeeEditor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lisa HarrisContributing Writers . . . . . . Kathryn Jensen, Rose Lichtenberg, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Robert L. Parsons

KUTC Resource and Education Staff

Traffic and Hwy. Engineering . . . . . . . Joe Lee / Tom MulinazziRoad Surface Mgmt./Soils . . . . . . . . . Steve Cross/ Bob ParsonsBridge Structures, GIS and CAD . . . . . . . . . . . . . . . Carl KurtMass Transit Planning . . . . . . . . . . . . . Pat Weaver/ Alan BlackSpecialized Transportation . . . . . . . . . . . . . . . . . . . . Pat WeaverEngineering Computer Applications . . . . . . . Mehrdad GivechiDrainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dave ParrEnvironmental Engineering . . . . . . . . . . . . . . . . . Dennis LanePublications Editor (785) 864-2590 . . . . . . . . . . . . . Lisa HarrisWorkshops Coordinator (785) 864-2594 . . . . Rose LichtenbergLending Library Coordinator (785) 864-5658 . . Jennifer Noblitt

2000/2001 LTAP Program Advisory Committee

Ron Bonjour . . . . . . . . .County Engineer, Montgomery CountyDennis Clennan . . . . . . . . . . . . . Public Works & Engineering,

City of HutchinsonLarry Emig . . . . . . . . . . . . . . . . . . . . . . Local Projects, KDOTSteve Foust . . . . . . . . . . . . . . . . . . . . .Kansas Division, FHWAMark Huffhines . . . . . . . . . . . . . . . . . .Kansas Division, FHWAWilliam Jacobs . . . . . . . . . . . . Research and Materials, KDOTGlenn Larson . . . . . . . . . . . . . . . .Public Works Administrator,

Washington CountyRichard Maginot . . . . Business Administrator, Soldier TownshipJ. R. McMahon II . . . . . Roads Superintendent, Miami CountyMike Novak . . . . . . . . . . . . . . . . . . . . . .City Engineer, LenexaJames Pickett . . . . . . . Kirkham, Michael, & Assoc., LewisburgGene Russell . . . . . . Civil Engineering, Kansas State UniversityRichard Teaford . . . . . . . . . .County Engineer, Jefferson CountyWarren Chip Woods . . . . . . . . County Engineer, Lyon County

The University of KansasKUTC NewsletterK. U. Transportation Center1530 W. 15th St., Room 2011Lawrence, Kansas 66045-7609

Address Correction Requested

PRSRT STD

U.S. Postage

PAID

Lawrence, Kansas

Permit No. 65

Kansas LTAP

co-sponsored by the FHWA and KDOT