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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