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PCCP WorkshopINDOT

▪ INDOT/ACPA Technical Committee

2009 Specification Revisions2009 Test Method RevisionsStudies

INDOT/ACPA Technical Committee

Materials ManagementFHWAConstruction ManagementDistrict Construction District TestingResearchIndustry

SpecificationsTest MethodsMiscellaneous ProblemsCost Savings Items

Concrete Mix Criteria

Minimum Cement Content reduced from 440 lbs/yd3 to 400 lbs/yd3

Phase I JTRP study on Optimization of Mixture Proportions indicated no compromise to strength, durability or performance

Concrete Mix Designs

New Trial Batches for material and source changes:

Very expensiveTime consuming for Contractor and INDOTHas caused delays in contracts

Weight (lb)

Volume (ft3)

One yd3

Materials SSD Batch

A 1.755 Air I 0 O

B 2.582 Cement J 507.6 P 508

C 0.452 Fly Ash K 70.5 Q 71

D 4.929 Water L 307.5 T(29gal)242

Paste (E) 9.718

Aggregate (F) 17.282

G 6.567 Fine Aggregate M 1073.6 R 1115

H 10.715 Coarse Aggregate N 1785.2 S 1810

Total (E + F) 27.0

Concrete Mix Designs

Streamline the ProcessReduce the number of Trial Batches because of change in materials or sourcesAllow more mixtures to be used without a Trial Batch

Weight (lb)

Volume (ft3)

One yd3

Materials SSD Batch

A 1.755 Air I 0 O

B 2.582 Cement J 507.6 P 508

C 0.452 Fly Ash K 70.5 Q 71

D 4.929 Water L 307.5 T(29gal)242

Paste (E) 9.718

Aggregate (F) 17.282

G 6.567 Fine Aggregate M 1073.6 R 1115

H 10.715 Coarse Aggregate N 1785.2 S 1810

Total (E + F) 27.0

Concrete Mix Designs QC/QA PCCP (501)

Submit CMDS to DTE on spreadsheet for approvalCMDS used to conduct Trial Batch

Concrete Mix Designs

Trial Batch conductedContractor submits Trial Batch results with the CMDSEliminate CMDT

Concrete Mix Designs

CMDP submitted 3 working days prior to production

Change in Materials

New CMDS with Trial Batch or Verification

Cement source and typePozzolan source or typeCoarse aggregate source or typeAdmixture type

Change in Materials Verification

Contractor and INDOT tests on first day of productionAcceptance tests may be used for verificationProduction may continue until flexural strength tests are completedMinimum 570 psi

Change in Materials Verification

Does not meet 570 psiStop ProductionFailed Material

Adjustments in Materials –Requires new CMD Submittal

Admixture sourceAdmixture product of the same type and from the same sourceFine aggregate sourceTarget unit weight due to change in aggregate propertiesFine to total aggregate ratio beyond ± 3%Increase in cement content

Adjustments in Materials

Trial Batch not requiredCMDS submitted to DTE for approval as CMDP one work day prior to production

Other Adjustments Allowed

Admixture dosage rateFine to total aggregate ratio within ±3%

No Trial Batch requiredNo DTE notification

Trial Batch

Concrete produced at plant by proportioning tolerances of 508.02 (b)

Concrete produced in lab – ASTM C 192

Trial Batch RequirementsAir Content -- 5.0% to 10.0%Plastic Unit Weight --within ± 3.0% of CMDS targetW/C Ratio -- within ±0.030 of CMDS target and does not exceed 0.450Flexural Strength --minimum of 570 psi at 7 days for average of two beams

No Trial Batch

Minimum cement content of 564 lbs/yd3

and target W/C ratio of 0.420Class C concrete in accordance with 702 using class AP coarse aggregate

Non QC/QA PCCP -- 502Changes or Adjustments that require new CMDS to be submitted:

Cement source or typePozzolan source or typeAggregate source or typeAdmixture source or typeAddition or deletion of an admixtureProportioning of concrete – 502.04

Trial Batch for High Early Strength Concrete only

PCCP Patching -- 506

Same as 501

Dowel Bars & Tie Bars

Epoxy coated bars protected from exposure to ultraviolet light and moisture during storageOnce placed into work, epoxy coated bars shall not be exposed to ultraviolet light for a total of more than 21 days prior to placement of concrete

AASHTO/ASTM Revisions 2009

Review all test methods for revisions

▪ Materials Management▪ District/Production Labs▪ Independent Assurance Program▪ Qualified Technician Program▪ Training

AASHTO T 121 – Unit Weight

Strike – off plate is required instead of the strike – off bar

AASHTO T 23 – Making and Curing Test Specimens in the Field

Warning added –Hydraulic cementitious mixtures may cause burns to exposed skin and tissue upon long exposure

ASTM C 173 – Air Content by Volumetric Method

Requires scoop to be moved around the perimeter of the bowl opening to ensure even distribution of concrete with minimal segregation

Certified Ready Mixed Plant Program

NRMCA Plant CertificationMore frequent scale calibrations2 year cycle for inspection of plantVoluntaryINDOT inspection

Certified Ready Mixed Plant Program

Delivery Vehicles included14 month cycle for certification

Aggregates - CAPP Certified Sources – 193

• Sand & Gravel – 104• Stone – 70• Sand, Gravel, & Stone – 8• Slag - 11

CAPP SOURCES1995 - 81996 - 61997 - 511998 - 831999 - 19 2000 - 142001 - 15

2002 - 92003 - 72004 - 82005 - 52006 - 102007 - 62008 - 3

CERTIFIED MATERIALS

Stone -- 1275Natural Sand -- 207Gravel -- 183Blast Furnace Slag -- 58Steel Slag -- 16

AASHTO T 84 – Fine Aggregate Specific Gravity

Fine Aggregate Specific Gravity/Absorption

AASHTO T 84SubjectiveInfluenced by OperatorUnable to predict slumps in concrete -- absorption

SS DetectFine Aggregate Specific Gravity

● Sample is mixedby orbital motion

● Water added at 8 μl per injection for ¾ to 1 hours depending on absorption

●Infrared light source “tuned” to water

● Stops when water is detected

Automated Vacuum Machine

● Agitates aggregate● Vacuums air from

sample● Agitate → 3 min

Vacuum → 3 min @ 22 in. Hg

Vacuum → 5 min @ 27 in. Hg

SS DetectFine Aggregate Specific Gravity

Natural Sand –good comparison with AASHTO T 84 procedureStone Sand –amount passing No. 200 sieve

Volumetric Immersion Method

Normal absorptions are relatively small, so a large amount needs to be tested to allow accurate measurement of total absorbed water

Fine Aggregate Specific Gravity/Absorption

Desired CharacteristicsEasy to performEasy to understandEasily re-producedOperator and laboratory independent

Volumetric Immersion Method

Physically and visually measure:

total amount of water absorbed into the samplevolume displacement of dry samplevolume displacement of saturated sample

Volumetric Immersion Method

Large flask1200 g sampleSubmerge sample in flaskShake and roll flask for 3 min and read after 5 minRepeat and read after 10 min, 30 min, 60 min, 2hr, 4 hr, and 25 ± 1 hr

Volumetric Immersion Method

Absorptions are much differentSpecific gravity values areslightly higher

Volumetric Immersion Method

Impact to PCCPAbsorptions Slight adjustments to fine aggregate for yield

Slight change to Maximum Theoretical Unit Weight

Studies

PCCP Joint StudyAP Study – Sonic ModulusSmoothnessTop Size of AggregateRecycled ConcreteDepth of Concrete

Premature Distress around Joints

5-10 yr old pavementsLongitudinal and transverse jointsSR 933I-6586th StGeorgetown Rd.

Possible Solutions

Current procedure of initial saw cut, followed by a second saw cut, and then placement of a backer rod may be trapping water in the jointSolution – possibly require one 1/8 in. saw cut, leave joint open, and seal joint faces

Class AP Coarse AggregatesITM 210

"D" Cracking

AP Study

Investigate material in the marginal performing aggregates – Louisville formationFind a possible predictor for the AP test

High insoluble residueHigh clay contentPorosity

AP Study -- Sonic Modulus

Measure modulus of elasticityAdditional information that may be used to evaluate aggregates

AP AggregateSources – 92

Stone – 62Gravel – 26BF Slag – 4

DistrictsCrawfordsville - 9Ft. Wayne - 8Greenfield - 25LaPorte - 16Seymour - 24Vincennes - 9

Smoothness

Ramps and Turn Lanes included in profilograph requirements – design speed of mainline and lengths > 0.1 mi. lengthUrban Streets & Signalized Locations

Smoothness Inertial Profilers

Measures IRI which is used in design processProvides smoothness value upon completion of testingMore repeatableGood correlation with user responseTrue profile measurementPCCP tines – line lasers

Smoothness Inertial Profilers

Who will do testingTiming of evaluations during constructionIncentives related to expected pavement performanceIdentification and remediation of irregularities such as bumpsComplete by June, 2010

Top Size of Aggregate

Phase II of JTRP study 0n Optimization of Mixture Proportions for Concrete PavementsReduction in surface area – cementAP testing – size of freezer rack & molds

Recycled Materials

Blast Furnace SlagSlag CementFly AshGround Granulated Blast Furnace Slag Recycled Concrete

SubgradesConcrete

Recycled Concrete in Concrete

Unhydrated cement and finesD-Cracking

CARRIAGE

DROP SCALES

STANDARD STEEL RULE

VERTICALSHAFT

100 mm (4.0 IN.)

BASE

Figure # 1

PCCP Core Length

Drainage Layer - No. 8 stone or ACBFITM 404 -- Removal of particles not substantially surrounded by mortarDemonstrated to Contractor on each contract

Depth of Concrete

Provides quicker resultsSave expense of coringSave time of testingCost savings by Contractor not having to compensate bid for concrete lost in the subbase material

PCCP Rutting

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