PCCP Workshop INDOT
INDOT/ACPA Technical Committee 2009 Specification Revisions 2009 Test Method Revisions Studies
INDOT/ACPA Technical Committee Materials Management FHWA Construction Management District Construction District Testing Research Industry Specifications Test Methods Miscellaneous Problems Cost Savings Items
Concrete Mix Criteria Minimum Cement Content reduced from 440 lbs/yd 3 to 400 lbs/yd 3 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 expensive Time consuming for Contractor and INDOT Has caused delays in contracts
Concrete Mix Designs Streamline the Process Reduce the number of Trial Batches because of change in materials or sources Allow more mixtures to be used without a Trial Batch Volume (ft 3 ) One yd 3 Materials SSD Weight (lb) A 1.755 Air I 0 O Batch 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 Paste (E) 9.718 Aggregate (F) 17.282 G 6.567 H 10.715 Total (E + F) 27.0 Fine Aggregate Coarse Aggregate T(29gal)24 2 M 1073.6 R 1115 N 1785.2 S 1810
Concrete Mix Designs QC/QA PCCP (501) Submit CMDS to DTE on spreadsheet for approval CMDS used to conduct Trial Batch Volume (ft 3 ) One yd 3 Materials SSD Weight (lb) A 1.755 Air I 0 O Batch 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 Paste (E) 9.718 Aggregate (F) 17.282 G 6.567 H 10.715 Fine Aggregate Coarse Aggregate T(29gal)24 2 M 1073.6 R 1115 N 1785.2 S 1810 Total (E + F) 27.0
Concrete Mix Designs Trial Batch conducted Contractor submits Trial Batch results with the CMDS Eliminate 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 type Pozzolan source or type Coarse aggregate source or type Admixture type
Change in Materials Verification Contractor and INDOT tests on first day of production Acceptance tests may be used for verification Production may continue until flexural strength tests are completed Minimum 570 psi
Change in Materials Verification Does not meet 570 psi Stop Production Failed Material
Adjustments in Materials Requires new CMD Submittal Admixture source Admixture product of the same type and from the same source Fine aggregate source Target unit weight due to change in aggregate properties Fine to total aggregate ratio beyond ±3% Increase in cement content
Adjustments in Materials Trial Batch not required CMDS submitted to DTE for approval as CMDP one work day prior to production
Other Adjustments Allowed Admixture dosage rate Fine to total aggregate ratio within ± 3% No Trial Batch required No DTE notification
Trial Batch Concrete produced at plant by proportioning tolerances of 508.02 (b) Concrete produced in lab ASTM C 192
Trial Batch Requirements Air Content -- 5.0% to 10.0% Plastic Unit Weight -- within ± 3.0% of CMDS target W/C Ratio -- within ± 0.030 of CMDS target and does not exceed 0.450 Flexural Strength -- minimum of 570 psi at 7 days for average of two beams
No Trial Batch Minimum cement content of 564 lbs/yd 3 and target W/C ratio of 0.420 Class C concrete in accordance with 702 using class AP coarse aggregate
Non QC/QA PCCP -- 502 Changes or Adjustments that require new CMDS to be submitted: Cement source or type Pozzolan source or type Aggregate source or type Admixture source or type Addition or deletion of an admixture Proportioning 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 storage Once 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 Certification More frequent scale calibrations 2 year cycle for inspection of plant Voluntary INDOT inspection
Certified Ready Mixed Plant Program Delivery Vehicles included 14 month cycle for certification
Aggregates - CAPP Certified Sources 193 Sand & Gravel 104 Stone 70 Sand, Gravel, & Stone 8 Slag - 11
CAPP SOURCES 1995-8 1996-6 1997-51 1998-83 1999-19 2000-14 2001-15 2002-9 2003-7 2004-8 2005-5 2006-10 2007-6 2008-3
CERTIFIED MATERIALS Stone -- 1275 Natural Sand -- 207 Gravel -- 183 Blast Furnace Slag -- 58 Steel Slag -- 16
AASHTO T 84 Fine Aggregate Specific Gravity
Fine Aggregate Specific AASHTO T 84 Subjective Gravity/Absorption Influenced by Operator Unable to predict slumps in concrete -- absorption
SS Detect Fine Aggregate Specific Gravity
Sample is mixed by 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 Detect Fine Aggregate Specific Gravity Natural Sand good comparison with AASHTO T 84 procedure Stone 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 Characteristics Easy to perform Easy to understand Easily re-produced Operator and laboratory independent
Volumetric Immersion Method Physically and visually measure: total amount of water absorbed into the sample volume displacement of dry sample volume displacement of saturated sample
Volumetric Immersion Large flask 1200 g sample Method Submerge sample in flask Shake and roll flask for 3 min and read after 5 min Repeat and read after 10 min, 30 min, 60 min, 2hr, 4 hr, and 25 ± 1 hr
Volumetric Immersion Method Absorptions are much different Specific gravity values are slightly higher
Volumetric Immersion Method Impact to PCCP Absorptions Slight adjustments to fine aggregate for yield Slight change to Maximum Theoretical Unit Weight
Studies PCCP Joint Study AP Study Sonic Modulus Smoothness Top Size of Aggregate Recycled Concrete Depth of Concrete
Premature Distress around Joints 5-10 yr old pavements Longitudinal and transverse joints SR 933 I-65 86 th St Georgetown 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 joint Solution possibly require one 1/8 in. saw cut, leave joint open, and seal joint faces
Class AP Coarse Aggregates ITM 210
"D" Cracking
AP Study Investigate material in the marginal performing aggregates Louisville formation Find a possible predictor for the AP test High insoluble residue High clay content Porosity
AP Study -- Sonic Modulus Measure modulus of elasticity Additional information that may be used to evaluate aggregates
Sources 92 Stone 62 Gravel 26 BF Slag 4 Districts Crawfordsville - 9 Ft. Wayne - 8 Greenfield - 25 LaPorte - 16 Seymour - 24 Vincennes - 9 AP Aggregate
Smoothness Ramps and Turn Lanes included in profilograph requirements design speed of mainline and lengths > 0.1 mi. length Urban Streets & Signalized Locations
Smoothness Inertial Profilers Measures IRI which is used in design process Provides smoothness value upon completion of testing More repeatable Good correlation with user response True profile measurement PCCP tines line lasers
Smoothness Inertial Profilers Who will do testing Timing of evaluations during construction Incentives related to expected pavement performance Identification and remediation of irregularities such as bumps Complete by June, 2010
Top Size of Aggregate Phase II of JTRP study 0n Optimization of Mixture Proportions for Concrete Pavements Reduction in surface area cement AP testing size of freezer rack & molds
Recycled Materials Blast Furnace Slag Slag Cement Fly Ash Ground Granulated Blast Furnace Slag Recycled Concrete Subgrades Concrete
Recycled Concrete in Concrete Unhydrated cement and fines D-Cracking
PCCP Core Length Drainage Layer - No. 8 stone or ACBF ITM 404 -- Removal of particles not substantially surrounded by mortar Demonstrated to Contractor on each contract STANDARD STEEL RULE VERTICAL SHAFT CARRIAGE DROP SCALES 100 mm (4.0 IN.) BASE Figure # 1
Depth of Concrete Provides quicker results Save expense of coring Save time of testing Cost savings by Contractor not having to compensate bid for concrete lost in the subbase material
PCCP Rutting