Transcript MDOT Specifications for Concrete Acceptance
2015 APAM Conference Hot Mix Asphalt (HMA) Update
Kevin Kennedy HMA Operations Engineer Michigan Department of Transportation 4-22-15
Hot Mix Asphalt (HMA) Update
• Acceptance of HMA on Local Agency Projects • HMA Quality Improvements • Portable Plants and Utilizing Recycled Asphalt Pavement (RAP) from the same project • Recycled Tire Rubber Permissive Specification • Miscellaneous Specification Changes • HMA Production Manual • National Peer Review
Acceptance of HMA on Local Agency Projects
• New Specification Approved • Immediate Use- NHS Routes and Routes Chosen by Local Agency • Full Implementation October 2015 • Interim- Old Specification With Minor Revisions or New Specification • Covers Roller Method and Density Testing with Nuclear Gauge • Revises Tolerance Limits and Penalty Structure for HMA Mixtures • Strengthens Sampling and Testing Requirements • Adds Time Frame for Reporting Quality Assurance Test Results
Local Agency- Tolerance Limits
Table 1 –Uniformity Tolerance Limits for HMA
Number
1 2
Parameter Description
% Binder Content # 8 and Larger Sieves # 30 Sieve # 200 Sieve Crushed Particle Content (b)
Top and Leveling Course Range 1 (a) Range 2
-0.30 to +0.40
± 0.50
± 5.0
± 8.0
± 4.0
± 6.0
± 1.0
± 2.0
Below 10% Below 15%
Base Course Range 1 (a) Range 2
-0.30 to +0.40
± 0.50
± 7.0
± 9.0
± 6.0
± 9.0
± 2.0
± 3.0
Below 10% Below 15% 3 a. This range allows for normal mixture and testing variations. The mixture must be proportioned to test as closely as possible to the Job-Mix-Formula.
b. Deviation from Job-Mix-Formula.
Acceptance of HMA on Local Agency Projects Sampling and Testing Requirements
• All persons performing testing must be Bituminous (Bit) Level One certified or Bit Quality Assurance/Quality Control (QA/QC) Technician certified.
• All laboratories performing local acceptance testing must be qualified laboratories.
o Qualified per the HMA Production Manual and participate in the MDOT Round Robin process o or Laboratory must be AASHTO Materials Reference Laboratory (AMRL) accredited for AASHTO T 30 or T 27, and AASHTO T 164 or T 308.
• Contractor Laboratories: o Non-NHS: Allowed o NHS: Not Allowed
Acceptance of HMA on Local Agency Projects Sampling and Testing Requirements
• Qualified Samplers Required o Qualifying of Samplers to be handled by Ferris State University o MTM 313 (Sampling HMA Paving Mixtures) o MTM 324 (Sampling HMA Paving Mixtures Behind the Paver) • Minimum – Obtain and test two samples per day o No longer testing at frequency determined by engineer • Quality Assurance Test Results – Time Requirement o 7 days – projects more than 5000 tons o 14 days – projects less than 5000 tons
Acceptance of HMA on Local Agency Projects Penalty Structure Table 3: Penalty Per Parameter Mixture Parameter out-of-specification per Acceptance Tests Mixture Parameter out-of specification per Dispute Resolution Test Lab Price Adjustment per Parameter
NO YES N/A NO None None Outside Range 1 but not Range 2: decrease by 10% YES Outside Range 2: decrease by 25% Out of specification- 2 consecutive tests outside of range 1 or range 2
•
Acceptance of HMA on Local Agency Projects Density Testing
Two Options o Direct Density Method • • Nuclear density gauge 92-98 percent of density control target (Gmm from JMF) o Roller Method • Added table for Minimum Number of Rollers Recommended Based on Placement Rate • Added table for Density Frequency Curve Development. • Timing o During paving operations o Prior to traffic staging changes o Prior to subsequent lifts and opening to traffic
Acceptance of HMA on Local Agency Projects Additional Significant Changes
• Regress air voids in production to 3.5% • Dispute Process o Range 1- Independent Laboratory o Range 2- Construction Field Services HMA laboratory (MDOT Central Laboratory)
Acceptance of HMA on Local Agency Projects Future Changes
• Move towards volumetric testing • Air Voids, VMA, ??
• Doesn’t Necessarily Mean SuperPave • Sampling Behind the Paver/Mini-Stockpile
HMA Quality Improvements
• Regress Mixes to 3% Air Voids • Requiring Fine-Graded or Gap-Graded for Top Courses • Ride Quality Incentive
Quality –Regress High Volume Mixes
• Regress Mixes to 3% Air Voids in Production for E10, E30 and E50 Mixes • Effective October Letting Table 3- For mixtures meeting the definition for top and leveling courses: Mixtures must be designed to 96.0% of Maximum Specific Gravity (%Gmm) at the design number of gyrations, (Nd). During
field production Percent of Maximum Specific Gravity (%Gmm) at the design number of gyrations, (Nd) will be increased to 97.0% for
E10, E30, & E50 mixes. For all other mixes, Percent of Maximum Specific Gravity (%Gmm) at the design number of gyrations, (Nd) will be increased to 96.5% during field production.
Quality - Regress All Mixes
• Regress Mixes to 3% Air Voids in Production For All Mixes • Effective March Letting Unless noted otherwise on the plans, all mixtures must be designed to 96.0% of Maximum Specific Gravity (%G mm ) at the design number of gyrations, (N d ). During field production Percent of Maximum Specific Gravity (%G mm ) at the design number of gyrations, (N
d ) will be increased to 97.0%.
Quality - Regress All Mixes
• Additional Changes • Changing the upper air voids limit on single test acceptance (changed to 2.0 from 2.5) • Changing suspension limits in Table 4 for binder content (changed from 1.00 to 0.75) • Changing the sublot Rejectable Quality Limits (RQL) for air voids (changed to +2, -1.5 from +2,-2) • Adding removal limits for lots on one course overlays (501V)
Quality - Regress All Mixes
Table 4
Col. I - Quality Characteristic Aggregate Gradation (optional) Aggregate Moisture Binder Content Col. II - QC Action Limits (a) ± 0.50 JMF Combined Mixture Gradation Maximum Theoretical Specific Gravity Defined in the HMA QC Plan ± 0.013 JMF Bulk Specific Gravity Col. III - QC Suspension Limits (b)
± 0.75 JMF
Refer to Table 2 ± 0.020 JMF Col. IV - QA Suspension Limits Form 1165 (a) Col. V - Sublot RQL Form 1165 (c) Col. VI - Lot AQL (d) PWL BINDER ≥ 90 For any lot Col. VII - Lot RQL
PWL
(d)
BINDER < 50 For any lot
Volumetrics: Air Voids Volumetrics: VMA Fines to Effective Binder Defined In the HMA QC Plan Defined In the HMA QC Plan ± 1.00 of Target Air Voids Defined In the HMA QC Plan ± 1.00 of VMA Targets in Table 3 0.60 – 1.40 (a) 0.60 – 1.40
+ 2.00, -1.50 of Target Air voids
PWL AV ≥ 90 For any lot ± 2.00 of VMA Targets in Table 3 PWL VMA ≥ 90 For any lot
PWL AV < 50 For any lot PWL VMA < 50 For any lot
a.
b.
c.
d.
In-Place Density Defined in the HMA QC Plan Defined in the HMA-QC Plan Average Sublot Value < 90.00% Limits apply to two consecutive QC or QA tests.
Limits apply to single QC tests.
Specified. Limits apply to a single QA sublot Air Void or VMA test or on the sublot average In-Place Density.
Specified. Limits apply on a lot-by-lot basis. Based on QA results for the lot.
PWL D ≥ 90 For any lot
PWLD < 50 For any lot
Quality –Fine Graded/Gap Graded on Top Course
• Changed Gradation to Eliminate Coarse Graded Mixes • Eliminated Restricted Zone • FUSP 902E • Effective January Letting • Revises Table 902-5 and 902-6
Quality – Fine Graded/Gap Graded on Top Course
Standard Sieve 1½ in 1 in ¾ in ½ in ⅜ in No. 4 No. 8 No. 16 No. 30 No. 50 No. 100 No. 200 5 — — Revised Table 902-5 4 Superpave Final Aggregate Blend Gradation Requirements Percent Passing Criteria (control points) 3 Leveling Course Mixture Number 3 Base Course 2 — — — 100 — 100 100 90–100 — 100 90–100 100 90–100 ≤90 90–100 ≤90 — 90–100 ≤90 — ≤90 — — ≤90
47-67
—
39-58
—
35–49
— 23–49 — 19–45 — — — — — — — — — — — — — — — — — — — — 2.0–10.0
2.0–10.0
2.0–8.0
2.0–8.0
1.0–7.0
a. For LVSP, less than 50 percent of the material passing the No. 4 sieve may pass the No. 30 sieve.
LVSP (a) — — 100 75–95 60–90 45–80 30–65 20–50 15–40 10–25 5–15 3–6
Quality –Fine Graded/Gap Graded on Top Course
Revised Table 902-6 Superpave Final Aggregate Blend Physical Requirements Percent Crushed Minimum Criteria Est. Traffic (million ESAL) < 0.3
< 0.3
>0.3 -<1.0
>1.0 - < 3 >3 - <10 Mix Type
LVSP E03 E1 E3 E10
Top & Leveling Courses
55/ — 55/ — 65/ — 75/ — 85/80
Base Course
— — — 50/ — 60/ —
Fine Aggregate Angularity Minimum Top & Leveling Courses
— — 40
43
45
Criteria Base Course
— — — 40 40
% Sand Equivalent Minimum Criteria Top & Leveling Courses
40 40 40 40 45
Base Course
40 40 40 40 45
Los Angeles
45 45 40 35 35
Abrasion % Loss Minimum Criteria Top & Leveling Courses Base Course
45 45 45 40 40
% Soft Particles Maximum Criteria Top & Leveling Courses
10 10 10 5 5
(a) Base Course
10 10 10 5 5
% Flat and Elongated
— — — 10 10
Particles Maximum Criteria Top & Leveling Courses (b) Base Course
— — — 10 10
>10 - <30
E30 95/90 80/75 45 40 45 45 35 35 3 4.5
10 10 (a) (b)
>30 <100
E50 100/100 95/90 45 45 50 50 35 35 3 4.5
10 Soft particles maximum is the sum of the shale, siltstone, ochre, coal, clay-ironstone and particles that are structurally weak or are non-durable in service.
Maximum by weight with a 1 to 5 aspect ratio.
10 Note: “85/80” denotes that 85 percent of the coarse aggregate has one fractured face and 80 percent has at least two fractured faces.
Quality – Ride Quality Incentive
• Specification Approved (12RC501-A435) • Incentive Starts at IRI of 45 • Increases to $.50 per square yard at IRI of 25 • Applies to High Speed Roads (50 MPH) • Class I and Class II Roads per Ride Quality Specification
Portable Plants- RAP
Stockpile Requirements. Process RAP to the size required for the specified HMA mix. Ensure the stockpile contains enough material to produce the recycled mixtures the Engineer approves for the project. If the RAP stockpile is not sufficient to produce recycled mix quantities required for the project, provide an Engineer-approved mix design without RAP at the same unit price.
Requirements for Utilizing RAP Millings from the Same Project When Using a Portable Plant
Sampling • • • • • Samples to be taken a minimum of every mile in each lane by milling or coring. Sample areas to be repaired.
Shoulder samples should also be taken if RAP from shoulder is to be used.
Samples should also be taken if visual observations show significant variations in existing mat.
Sampling required for the percentage/tonnage of RAP that will be utilized on the project.
Requirements for Utilizing RAP Millings from the Same Project When Using a Portable Plant
Mix Design • A sufficient amount of millings or cores shall be taken at each test location to ensure an adequate amount of RAP is obtained to perform a full mix design.
• No paving shall occur using RAP from the project until a mix design is approved.
Requirements for Utilizing RAP Millings from the Same Project When Using a Portable Plant
Processing RAP • It is not required to have a stockpile with enough material to • • produce the recycled mixtures approved for the project.
RAP should be stockpiled* and tested according to existing requirements (one test per 1000 tons, minimum of 3 tests).
If the millings have aggregates larger than what it is required for the mix design, it should be processed (crushed and/or screened) prior to stockpiling*. If aggregates larger than what is required for mix design still exist after processing, the contractor must demonstrate that additional screens are installed on the RAP feed system to ensure that the RAP being introduced into the HMA Mixture contains no aggregate larger than the top size aggregate allowed in the mix design.
Requirements for Utilizing RAP Millings from the Same Project When Using a Portable Plant
Processing RAP • In addition, a RAP scalper screen is required**. The top size of the top scalping screen shall be 1.5” for top and leveling courses and 2” for base courses.
*If approved by the engineer, in-line crushing and/or screening will be allowed in lieu of processing RAP into a stockpile. The contractor must demonstrate that additional screens are installed on the RAP feed system to ensure that the RAP being introduced into the HMA Mixture contains no aggregate larger than the top size aggregate allowed in the mix design. **If in line crushing and/or screening is being used a RAP scalper screen may not be required.
Recycled Tire Rubber
• Grand Region Pilot Project – 2013 • M-57 from East of Northland Drive to West of Morgan Mills Avenue • Crumb rubber portion approximately 3.2 miles on M-57 between Wabasis Road and Morgan Mills • Allowed Wet Process or Terminal Blend (contractor’s option) • Three binders (64-22, 70-22P, 70-22 crumb rubber modified) • 6,007 tons HMA 5E3 Crumb Rubber Modified • Bids • • Low Bidder- $79.45 vs $85.83
2 nd Bidder- $71.15 vs $102.97
MDOT Pilot Project
Recycled Tire Rubber
• HMA Tech Committee Directed to Develop Permissive Specification o Originally- specification to mirror pilot project o Concern over reports of poor performance (Waverly Road, Haslett Road, various Saginaw County projects) o PG Binder performance tests have been modified or waived o HMA Technical Committee believes revised tests do not accurately predict performance o No deviations to acceptance test methods/procedures allowed.
Waverly Road
2011 Construction County Road (Photo taken in 2013)
Miscellaneous Specification Changes
• FUSP 501G (RAP/RAS)- Added language referring to production manual for blending charts: • When incorporating RAS the asphalt binder grade will be selected using a blending chart for high and low temperatures.
• The Contractor must supply the blending chart used in determining the binder selection according to AASHTO M 323 and the HMA Production Manual.
• FUSP 501L (Temp Pavement) - Added language clarifying removal of temporary pavement is not part of temporary pavement pay item
Miscellaneous Specification Changes
• Gap-Graded SuperPave- New specification for ½” nominal mix and 3/8” nominal mix • FUSP 504C (HMA ultra-thin overlay)- New specification , no longer Marshall mix. Includes mix design submittal requirements • HMA Binders- Changes coming to Price Adjustment and Certification procedures • Non-Tracking Bond Coat (Trackless Tack)
HMA Production Manual
• Bureau of Highway Instructional Memorandum 14-12 o Includes blending chart instructions for RAP/RAS.
o RAP now part of mix design submittal.
o Section 4 was removed from the MDOT HMA Production Manual and added to Section 5.03.01 of the MDOT Materials Quality Assurance
Procedures Manual (MDOT MQAPM).
National Peer Review
• • • • NCAT/NAPA/FHWA • Construction Best Practices • • Bond Coat Minimizing segregation • Longitudinal Joint Construction RAP/RAS – Are we doing it right?
Local Agency Acceptance (present and future) Mix Design • Aggregate/RAP specific gravity • Fine graded mixes