Pavement Preservation In Georgia

Pavement Preservation in Georgia

GDOT Pavement ManagementPractices

PM Practices in GDOTzzzzz18, 000 mile centerlinehighway.7 working districts.Pavement surveyed annuallywith about 60 engineers.10 different types ofdistresses surveyed (i.g.load cracking)Project rating is between 0and 100.

PM Practices in GDOT (cont)zzzzMore than 17 years of surveydata (1986 – 2004)Survey data used to determinesuitable maintenance andrehabilitation strategies.Total miles of projects treatedare subject to budgetavailability.13 Congressional districts inGeorgia and the budget for eachdistrict should be balanced.

Components in Pavement ManagementData AcquisitionData ManagementDecision SupportKnowledge Discovery

Benefits of Implementing IT-basedPavement Management System

BenefitszzzzzzData acquisition efficiency was improvedData quality was enhanced.Data can be utilized more often and moreeffectively.Treatment decisions were made moreaccurately and consistently.Provided the ability to manage moreeffective the pavement preservation ProgramOther benefits

PAVEMENT CONDITIONEVALUATION SYSTEM(P.A.C.E.S.)

P.A.C.E.S. RATING SYSTEM RATING SYSTEM FROM 0 TO 100RATINGS BASED ON ROADWAYDEFICIENCIESRATINGS PERFORMED YEARLYBETWEEN OCTOBER 1ST ANDDECEMBER 31st BY AREAASSISTANT FOR ENTIRE STATEHIGHWAY SYSTEM

P.A.C.E.S. (cont.) ROADWAY SECTIONS WITH RATINGSOF 75 AND BELOW BY THE AREA WILLBE RATED BY THE DISTRICT ANDGENERAL OFFICERATINGS OF 70 AND BELOWWARRANT RESURFACINGRATINGS ABOVE 70 MAY WARRANTOTHER TYPES OF TREATMENTS

P.A.C.E.S. (cont.) SAFETY CONCERNS, SUCH AS,ACCIDENT HISTORY OR SKIDRESISTANCE CAN OVERRIDEROADWAY RATING ASJUSTIFICATION FOR RESURFACING

DEFICIENCIES CONSIDEREDLoad Cracking Block Cracking Rutting Raveling ReflectiveCracking Loss of Section Bleeding Corrugation Edge Distress Patched Areas

Field Data AcquisitionField data acquisition is performed throughCOPACES module in GPAM.

Project-level Location Information

Segment-level Distress Information

LOAD CRACKING

Load CrackingClockwise from left: level 1, level 2, level 3, level 4

Block/Transverse CrackingClockwise from left: Level 1, level 2, level 3

Reflective CrackingFrom left to right: level 1, level 2, level 3

Other Distresses Other distresses considered during the survey are Patches, Potholes,Base Failures, Edge Distress, Rutting, Corrugations/Pushing,Bleeding/Flushing, Loss of section, and Raveling

RUTTING

RAVELING

Project Rating Calculation Determining Project Average for Each DistressSimple numeric averages for each distress are usedinstead of prorating in this rating system. The averagesare computed by totaling the values for each type ofdistress and dividing by the number of rating segments.After the average values are computed for each distressfor the project, deduct points are determined for eachdistress extent and severity. These deduct points aretotaled and subtracted from 100 to determine theproject rating.The following charts, used when PACES was performedmanually, are representative of the deduct point valuesused in COPACES.

ESTABLISHING YEARLY ROADWAYREHABILITATION PROGRAM EACH DISTRICT SUBMITS PRIORITIES TOSTATE MAINTENANCE OFFICE Priorities are based on PACES Rating, AADT,Safety History and Skid TestDistrict Maintenance Assistant and StateMaintenance Liaison establishes the District’spriorities

ESTABLISHING YEARLY ROADWAYREHABILITATION PROGRAM STATE MAINTNENANCE OFFICE REVIEWSEACH DISTRICT’S PRIORITY LISTING ANDESTABLISHES A STATE WIDE PRIORITYLISTING Priorities are based on available funding as wellas the items used at the district level

Patching

Crack Filling

Strip Sealing

Deep Base Repair

ResurfacingAsphaltic Concrete, Surface Treatment, & Spot Overlays

3 Asphalt Plants

Asphalt Plant LocationsAltoAugustaGreenville

ESTABLISHING YEARLY ROADWAYREHABILITATION PROGRAM (cont.) FOR INTERSTATES OR OTHER STATEROUTES WITH MAJOR DISTRESSES The State Maintenance Office requestsdetailed pavement and/or baseevaluation from the Office of Materialsand Research – Pavement DesignSection

Roadway Conditions in Georgia2006 State Route SystemRoadway Ratings37%63%Excellent, GoodFair, Poor, Bad

Roadway Conditions in GeorgiaRehabilitation Cost Curve70 Rating 270,000 / mile tooverlay 1.5 inches10050 Rating 600,000 / mileto reconstruct70RoadwayRating105Year1015

Resurfacing History in 5002.0%00.0%1999 2000 2001 2002 2003 2004 2005 2006 2007Miles of ResurfacingPercent o Routes Resurfaced

Projected Conditions in GeorgiaPercentage of State Routes with PACES Ratings 7090%80%70%60%50%2002200420062008201020122014

Extending Pavement Life

SMA Layer After 20 million ESAL’s at the NCAT Test Track,the Stone Mastic Asphalt (SMA) layer did notexhibited any rutting or other distresses.SMA is expensive relative to other mixes used byGDOT.SMA consists of cubical particles (3:1) with apolymer modified AC, a higher AC content andgood stone on stone contact.

SMA Layer SMA has been used by GDOT as a surfacelayer when AADT 50,000.SMA is also placed beneath the surfacelayer, the Open Graded Friction Course(OGFC), on Interstate routes.

Open Graded Friction Courses With repeated loading, OGFC will ravel and rut if theSMA and supporting layers are in poor condition.OGFC will only ravel if the SMA and supporting layers arein good condition.Based on NCAT Test results, GDOT decided to sacrificethe OGFC.This decision was supported by additional testing usingthe Asphalt Pavement Analyzer (APA).

Micromilling The milling process that sacrifices the OGFC iscalled “micromilling”.An Interstate maintenance project will serve asthe pilot project.Micro-milling will leave the high quality SMA mixin place, and micro-mill the surface over at leasttwo maintenance cycles.

Project Cores rutted 0.25 inches at theconclusion of the APA Test

Roller Compacted Concrete Roller Compacted Concrete is a relatively newaddition to the Pavement Design toolbox atGDOT.It has been used as a shoulder on an Interstateand a major state route.RCC has also been used in lieu of base material,where total pavement thickness was aconstraint.

RCC Shoulders along I-285

Questions?

Open Graded Friction Courses With repeated loading, OGFC will ravel and rut if the SMA and supporting layers are in poor condition. OGFC will only ravel if the SMA and supporting layers are in good condition. Based on NCAT Test results, GDOT decided to sacrifice the OGFC. This decision was supported by additional testing using the Asphalt Pavement Analyzer (APA).