quality assurance and quality control for pavement...
TRANSCRIPT
Quality Assurance and Quality Control for Pavement Preservation
Tuesday, April 3, 20182:00-3:30 PM ET
TRANSPORTATION RESEARCH BOARD
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requirements of the Registered Continuing Education Providers Program.
Credit earned on completion of this program will be reported to RCEP. A
certificate of completion will be issued to participants that have registered
and attended the entire session. As such, it does not include content that
may be deemed or construed to be an approval or endorsement by RCEP.
Purpose Discuss the needs of Quality Assurance/Quality Control (QA/QC) for pavement preservation in construction operations
Learning ObjectivesAt the end of this webinar, you will be able to:• Describe the QA/QC issues in chip seal construction• Identify components of QA/QC for emulsions and chip seal
construction• Describe how QA/QC is used on the NCAT and MNRoad test
tracks and identify how it may be applied to their agency
Quality Assurance/Quality Control for Pavement
PreservationModerated by: Judith Corley-Lay
Chairman of AHD18
Agenda
Dr. Youngsoo “Richard” Kim will describe research findings on the variability of emulsion and aggregate application rates from a project in NC.
Colin Franco will introduce the work and the work products of the Emulsion Task Force (ETF).
Todd Shields will discuss elements of the QC template that the ETF is drafting for chip seals.
Dr. Buzz Powell will describe the QA/QC processes used at NCAT and MinnRoad and how they might be applied to agency practices.
Questions from the chat box.
Sponsors
AHD18, the committee on Pavement Preservation, developed this webinar.
AHD20, the committee on Pavement Maintenance, is co-sponsoring.
You are invited to attend one or both of the committees at the January annual meeting.
Pavement Preservation:Quality Assurance Essentials
Quality Assurance For Emulsion Treatments
In Pavement Preservation
By: Colin A. Franco, P.E. – RIDOTTodd Shields – INDOT
Webinar – April 3, 2018
Webinar Outline
• ETF - Introduction
• ETF - Mission
• ETF - Accomplishments
• ETF - Looking Ahead
• Overview of QA
• QA Specification for Chip Seal
Emulsion Task Force (ETF) and Quality Assurance(QA)
PPETG
• ETF originally part of the FHWA PP ETG
• The ETF is an all volunteer stake holder working group
• ETF is now an AASHTO affiliated Group supported by the AASHTO TSP2 program
ETF
A. Develop Performance Based Methods and Specifications for Emulsions (SPG)
1) Develop a Surface Performance Grade Specification for Emulsion (SPG)
2) Develop Performance Based Specifications for Emulsion Treatments in AASHTO Format
• Materials - specifications and tests• Materials -Design practices• Construction -guide specs• QA specifications
ETF - Original MandateETF
B. Encourage Adoption of Uniform National Standards
1) AASHTO – TSP2
PP Regional PartnershipsAASHTO Comp
2) FHWA – (PP)ETG
3) TRB (Webinars)
ETF - Original Mandate (cont.)ETF
Co-Chair- Colin Franco RIDOTCo-Chair- Chris Lubbers - Kraton Polymers
Members From: - Industry: AEMA/ ARRA/ ISSA/FP2
- Academia: CSU/ Tx A&M/ U.WISC/ NC State- State DOT’s: TX, IN, RI, MN- FHWA & Federal Lands- National Center Pavement Preservation (NCPP)
Current Membership (2013 – Present)ETF
Emulsion Treatments Requiring AASHTO STDs1.Chip Seal2.Micro surfacing3.Tack Coat4.Fog Seal5.Scrub6.Sand Seal7.Slurry Seal8.Foam Asphalt Stabilization9.Bonded Surface Treatment (NOVA Chip)10.Cold Mixes
» Virgin» Recycled» CIR
ETF
AASHTO STANDARDS
Emulsion Treatments M / MP T / TP R W/ SOM Comments
Construction Guide
Specs Best Practices
Chip Seal MP27-16 PP82-16NCHRP 14-
37
Microsurfacing MP28-16 PP83-16NCHRP 14-
37
Tack Coat Y Y 2016 To SOM ballot
Fog Seal MP33-17 PP88-17NCHRP 14-
37
Scrub Seal Y Y 2017 To SOM ballot
Sand Seal Y Y 2017 To SOM ballot
Slurry Seal MP32-17 PP87-17
Foam Asphalt Stabilization
Cold Mixes
Reclamation: CIR MP31-17 PP86-17 NCHRP 9-62
Legend
Emulsion Binder Standards M / MP T / TP R W/ SOM Y = Approved by AASHTO
Emulsified Asphalt M140-16 M=Material Specs
Cationic Emulsified Asphalt M208-16 T=Test Methods
Polymer-Modified Cationic Emulsified Asphalt M316-16 R=Design Practices
P=Provisional
• Project Selection – Pavement Management / Asset Management
• Project Contract Development
PP Project Development
ETF
0
1
2
3
5
5 10 15 20 25 30
Very Poor
Poor
Fair
Good
Very Good
Time in Years
PSI =
ʃ(Dis
tress
)
Crack Seal($)
Surface Treatment($$)
PreservationRehab($$$)
4
PERFORMANCE ENHANCEMENT THROUGH PAVEMENT PRESERVATION
Reconstruction($$$$)
Preservation Treatments-Fog Seal/Scrub Seal-Tack Coats-Chip Seal-Slurry Seal-Micro and Microplus-Thin Overlays (TO)-TO Plus (sami)
ETFAsset Management Through Pavement Preservation
Pavement Preservation Project Development:1.Project Selection – for the STIP
• Pavement Management System
• Experience of Pavement/Maintenance Engineers
2.Project Design/Contract Documents
Materials standards and specs for Emulsion Treatments
• Materials Specifications (M-Stds)• Materials Tests (T-Stds)• Materials Design Practices (R-Stds)
ETF
(PP) Project Development (cont.)3. Construction guide Standards
• Construction Guide Specifications
4.Quality Assurance Specifications
• Acceptance Decision
• Quality Control
• Independent Assurance
• Certification
ETF
• Components of a QA Program for All Emulsion Treatmentsbased on 23 CFR 637
1) Materials QA:• Acceptance Testing (Agency)• QC - Quality Control (Contractor)• IA - Independent Assurance (Agency)• New Process / Product Acceptance Procedures
2) Materials Certification:• Acceptance Plans ( Agency)• QC Plans (Contractor)• Vendor Supplied Material Certifications
3) Workmanship QA:• Equipment Calibration• Construction Process Checks
QA Protocols - EmulsionETF
4) Education and Training:• Define the training needs for Agency / Contactor Staff• Education and Training Resources NHI TCCC Industry Sponsored Training
• Certification Program for Field Staff - Contractor & Agency
Note: National Center for Pavement Preservation is taking the lead on education and training.
QA Protocols – (Cont.)ETF
Pavement Preservation:Quality Assurance Essentials
Quality Assurance – Definition & Regulation
AASHTO R10 & TRB Circular E-C 037
• Quality Assurance – All those planned and systematic actions necessary to provide confidence that a product or facility will performsatisfactorily in service …
• QA Regulated through 23 CFR 637
QA Program
Agency Acceptance
Dispute Resolution
IndependentAssurance
Contractor QC
Lab Qualification
Personnel Qualification
Core Elements of aQuality Assurance Program • Establishes the core
programmatic elements required to achieve quality
materials and workmanship.
Quality Control - QC - “The system used by a Contractor
to monitor, assess and adjust their production or
placement processes to ensure that the final product will
meet the specified level of quality.”
Definition
Contractor Quality Control (QC)
Scope of Quality Control Activities
• Contractor’s QC system should address:
• Materials production processes
• Materials transportation and handling
• Field placement procedures
• Calibration and maintenance of equipment
• Activities (sampling, testing and inspection) to maintain each process in control
• Means to make timely adjustments and corrections
Contractor QC Operating Documents – QC Plan
• Quality Control Plan - A project specific document prepared by the contractor
which identifies QC personnel and procedures that will be used to maintain
production and placement processes in control and meet the
agency specification requirements.
QC Plan
Agency Acceptance Program
Agency determination of the quality of the
product as specified by the contract
requirements.
• Monitor adequacy of QC activity
• Verification Sampling and Testing – materials, products, and workmanship
• Inspection / Monitoring of Workmanship
Acceptance Function
• The primary objectives of agency acceptance are:
Measure the Quality of all materials produced
and placed by the contractor
Determine the corresponding payment
the contractor should receive
• Acceptance is not focused on directing the methods used to achieve conformance
Independent Assurance - “Activities that are an unbiased and independent evaluation of all the sampling and testing procedures used in the Quality Assurance Program”
Independent Assurance ( AASHTO R-44) - IA
• Performed by Agency or Agency Designee who are not directly responsible for project Acceptance sampling and testing
• Provides periodic independent evaluation of QC and Acceptancepersonnel and their equipment
• Not used to make a determination of work quality or acceptability of product
Independent Assurance – IA (cont.)
• Agency Central Laboratories
• Consultant Labs used for Independent Assurance (IA)
• Consultant Labs used for Dispute Resolution
Laboratory Accreditation (AASHTO R -18)Required For:
• Agency Laboratory
Qualification Program
For all other Labs performing
sampling and testing that are
utilized in the Agency’s
acceptance decision
Laboratory Qualification
• Formal training
• On-the-job training
• re-qualification intervals
• Proficiency demonstration • A written exam*• A process for
disqualification or decertification
A complete personnel qualification/certification program should include, at minimum:
Requirement for Personnel Qualification / Certification
*May be used for qualification
QA - Overview for Chip Seals
Todd Shields IN DOT
Chip Seal Construction Variability and Performance-Related
Specifications
Y. Richard KimJimmy D. Clark Distinguished University Professor
North Carolina State University
TRB Webinar onQuality Assurance and Quality Control for Pavement Preservation
April 3, 2018
Outline
• Field chip seal projects (2008 and 2016 experiments)
• Variation in application rates• Performance test results• Proposed performance-related specifications
Field Projects• 2008 Experiment 12 single seal, 9 double seal, 2 triple seal sections
constructed in Franklinton, NC Constructed by NCDOT Division crews Granite 78M and lightweight aggregate with CRS-2L
emulsion
• 2016 Experiment Three double-seal sections constructed in Rowan,
Moore, and Caswell Counties Constructed by two contractors and three
construction crews Granite 78M and granite #14 with CRS-2L emulsion Less than 100 vehicles/day
Test Section Details2008 Experiment
Aggregate Section # Target EARa (gal/yd2) Target AARb (lb/yd2)
Granite 78M
1 0.3 22
2 0.35 22
3 0.4 22
11 0.35 22
12 0.4 22
Lightweight
7 0.3 11
8 0.35 11
9 0.4 11
13 0.3 11
14 0.35 11
15 0.4 11a Emulsion application rateb Aggregate application rate
Test Section Details2016 Experiment
County Contractor/Crew Layer Aggregate Target EAR
(gal/yd2)Target AAR
(lb/yd2)
Rowan Contractor ACrew #1
Bottom Granite 78M 0.3 18
Top Granite #14 0.2 11
Moore Contractor ACrew #2
Bottom Granite 78M 0.24 26
Top Granite 78M 0.28 26
Caswell Contractor BCrew #1
Bottom Granite 78M 0.3 18
Top Granite #14 0.25 9
Sampling
Vialit Sample froma Single Layer
MMLS3 Double Seal
Sample
Test Methods2016 Experiment
Purpose Test MethodAAR and EAR Determination
(Individual Layers)Ignition Oven Test on Vialit
SamplesAggregate Loss and Bleeding
PerformanceThird-Scale Model Mobile
Loading Simulator (MMLS3)Emulsion Sprayability and
Drain-out Rotational Viscometer
High Temp. Binder Performance
Multiple Stress Creep and Recovery (MSCR) Test Using DSR
Third Scale Model Mobile Loading Simulator (MMLS3)
MMLS3 Test Preparation
MMLS3 Test Procedure
Curing@ 35°C12 hours
Temp.Conditioning@ 25°C1 hour
Agg. Retention Test @ 25°C2 hours 10 mins.
Bleeding Test@ 50°C4 hours
Temp.Conditioning@ 50°C2 hours
W W W W W
BPT, Laser, VS, TP BPTLaserVSTPW: Measurement of the Specimen Weight
BPT: British Pendulum TestLaser: Laser Profiler TestVS: Visual SurveyTP: Transverse Profiling
Rate ComparisonConstructed by NCDOT Division Crews (2008)
Granite LightweightLightweight Granite
% Difference in RatesConstructed by NCDOT Division Crews (2008)
AAR ComparisonConstructed by Contractors (2016)
Rowan Moore Caswell
EAR ComparisonConstructed by Contractors (2016)
Rowan Moore Caswell
% Difference in RatesConstructed by Contractors (2016)
Bottom BottomTop Top TotalTotal
MMLS3 Test Results2016 Experiment
County Contractor/Crew Avg. % Aggregate Loss
Avg. %Bleeding
Rowan Contractor ACrew #1 4.3 72
Moore Contractor BCrew #1 8.9 58
Caswell Contractor ACrew #2 6.0 98
% Bleeding vs. AAR/EAR
High Temperature PerformanceMSCR Jnr @ 67 °C
5.0
5.5
6.0
6.5
7.0
7.5
Rowan Moore Caswell
Jnr @
3.2
kPa
-1
Max. Jnr for low traffic = 8 kPa-1
Max. Jnr for medium traffic = 5.5 kPa-1
Same emulsion supplier
Higher probabilityof bleeding
Findings
• The EAR and AAR measured from the constructed field sections were significantly lower than the targeted rates regardless of contractors and crews.
• Field survey after 8 months from the 2016 construction showed no significant performance problems of chip seals. Lower rates in both EAR and AAR seemed to have canceled out the negative effects of lower rates. Also low ADT might delay the possible performance issues.
Findings (Cont’d)
• MMLS3 test results from the 2016 experiment Acceptable aggregate retention performance for all
three sections Rowan County and Caswell County exhibited
significant bleeding, with the Caswell section being the worst.
Possible causes: use of #14 choking layer, under-application of aggregate (low AAR/EAR ratio), high Jnr values in the Caswell section
Findings (Cont’d)
• Quality of materials, design application rates, and construction quality control are all important for well-performing chip seals!
• Need a comprehensive system to improve the quality of chip seals Performance specifications for materials Performance-engineered mix design Performance-related construction QA specification Pay factors
Performance Specifications for Materials
• Aggregate Performance Uniformity Coefficient (PUC) Maximum fine content Particle shape Abrasion resistance
• Emulsion (EPG system by NCHRP 09-50 project) Workability (storage stability, sprayability, drain-out) High and low temperature behavior using DSR Other tests, such as demulsibility, particle charge,
sieve test, solubility, float, and percent residue
EPG Tests for Chip Seal Emulsions
MSCR
Fresh EmulsionResidue
Minimum Jnr
G* at critical phase angle
DSR Temperature-Frequency Sweep RV
SprayabilityDrain-out Storage stability
(Supplier Spec)
Low Temperature Aggregate Loss
Bleeding Workability & Stability
Performance-Engineered Mix Design
• Determination of AAR: Modified Board Test• Determination of EAR: 50% embedment concept
using laser profiler• EAR adjustments based on existing surface
condition and aggregate absorption• Vialit test for aggregate-asphalt residue
bond strength
Performance-Related Construction QA Specification
Acceptance Quality
Characteristics
Related Performance
Measure
Proposed Test Method Test Parameter
Emulsion-Aggregate Adhesive Strength
Aggregate Loss Vialit Test (Lab) % Aggregate Loss
Gradation Aggregate LossGradation
Analysis of Vialit Samples (Lab)
Performance Uniformity Coefficient
Emulsion Application Rate
(EAR)
Aggregate Loss and Bleeding
Ignition Oven: Vialit Samples
% Difference from Target EAR
Aggregate Application Rate
(AAR)
Aggregate Loss and Bleeding
Ignition Oven: Vialit Samples
% Difference from Target AAR
PUC Limits
Higher Uniformity
y = -0.0111x + 24.641R² = 0.7493
0
5
10
15
20
25
0 500 1000 1500
% A
ggre
gate
Los
s
BBS (kPa)
Unmodified at 15CModified at 15CUnmodified at 25CModified at 25CPoor Performing at 15C
Vialit Aggregate Loss Limits
Low: AADT < 500• Max. Vialit Loss = 20%
Medium: 500<AADT<2500• Max. Vialit Loss = 17.5%
High: AADT > 2500• Max. Vialit Loss = 15%
Conclusions
• Variability of application rates in chip seals demonstrated
• Material quality is also important!• Need a comprehensive system to ensure high
quality chip seals Emulsion PG specification PUC-based aggregate specification Performance-Engineered Mix Design Performance-related construction QA specification
Chip Seal Quality Assurance Guide
TODD SHIELDS, INDIANA DOTTSP2 EMULSION TASK FORCE
What is the goal?
What we are trying to AVOID
So how do we get there?
Good specifications Good designs Qualified personnel
Contractor – actually running the equipment
Agency – overseeing and accepting
Solid Quality Assurance QA Specifications
QC Plans
Agency Acceptance Protocols
Independent Assurance
ETF Quality Assurance Guide
The guide includes: Contractor Quality Control Agency Acceptance Protocols Independent Assurance
Currently in DRAFT format Being reviewed/finalized by ETF
Contractor Quality Control Plan
Quality Control Plan is approved by the Agency Personnel
Require TSP2 certification for: Job Foreman
Recommend for: Agg Sreader Operator Distributor Operator
Testing Facilities Recommend AASHTO Accreditation Program Allow other accrediting body approved by Agency
Contractor Quality Control - Aggregate Gradation
Unit Weight
Bulk Specific Gravity
Flakiness Index
Aggregate Absorption
Fractured Faces
Deleterious Material
Application Rates
Contractor Quality Control - Emulsion Viscosity Temperature Residue Demulsibility Sieve Storage Stability Multiple Stress Creep Recovery (MSCR) Ductility Elastic Recovery Penetration Ash Content (cationic) Solubility (anionic) Application Rate
Require to be submitted at least 15 days prior to construction.
Requires details on: Scope – all applicable specifications
QC Organization – org chart, qualifications
Testing Facilities and Equipment – testing labs, equipment calibration
Materials Control – sources, stockpiling
QC Activities – Workmanship
Materials sampling locations
Test methods and Frequency
Inspection and Oversight
Contractor Quality Control Plan
Placement and Workmanship Calibration procedures
Method to monitor application rates
Method to ensure proper spread patterns
Rolling operations
Sweeping operations
Method to control traffic
Documentation – reporting procedures, sample test forms, reports
Non-Conformance and Corrective Action – method to identify and corrective action
QC tests submitted to Agency within 24 hours Include supplier material certifications
Contractor Quality Control Plan
Agency Acceptance Protocols Materials Sampling and Testing
Aggregate and Emulsion Testing
Vendor certifications Materials
Personnel
Surface Preparation Surface is clean and dry
Minor defects corrected
Construction Procedures Equipment calibrated and functioning correctly
Proper placement procedures followed
Post Placement Check for any issues
Bleeding, broken aggregate, raveling, joint laps, etc.
Independent Assurance
IA is conducted by the Agency
Purpose is to Evaluate for Adequacy Personnel skills
Equipment
Both agency acceptance testing and contractor QC testing
IA is NOT for determining if materials or processes are in spec
Once we all agree on the format and content…
Expand to include other treatments Micro/Slurry
Tack Coat?
Ultrathin Bonded Wearing Course
Next Steps
Preservation ConstructionQuality
NCAT+MnROAD Research Partnership
Buzz Powell
Content
• Background• Thinlays• Crack Sealing• Chip seals• Micro surface• Future
2
3
Background
Background
• Performance is function of quality & condition• High quality prevents confounded outcomes• Regionally appropriate materials, designs• Verify designs using actual onsite stockpiles• Same placement team at all south, north sites• Utilized best practices & test procedures• Successful placements at all south, north sites.
4
5
Thinlays
Thinlays
6
7
Crack Sealing
Crack Sealing
8
Crack Sealing
9
Crack Sealing
10
11
Chip Seals
Chip Seals
• Vulcan (south), Martin Marietta (north) granite• Ergon (south), Flint Hills (north) emulsions• Quarry designs, onsite verifications by Paragon• Vance Brothers placement contractor (Colas)• Off section equipment setup, calibration• Emulsion/chip rate determinations by NCAT• Northern inspection team provided by MnDOT.
12
Chip Seals
13
Chip Seals
14
Chip Seals
15
Chip Seals
16
Chip Seals
17
Chip Seals
18
Chip Seals
19
Chip Seals
20
Chip Seals
21
22
Micro Surface
Micro Surface
23
Micro Surface
• Regular calibration of micro paver is key• We won’t place thinlays with printed tickets !• Summer 2016 MnROAD test procedure trial• Chute sample, roadside mixing, lab testing• Oven moisture, furnace for residual binder• Gradation of uncoated aggregate blend• Draft test procedure submitted to ALDOT.
24
Micro Surface
25
Micro Surface
26
Micro Surface
27
Micro Surface
28
Micro Surface
29
30
Future
Future
• http://www.pooledfund.org/Details/Study/627• Support for implementation of products• Best practices & guide specifications• Training, technical support, field projects• Life extending & condition improving benefits.
31
Future
32
“Fair”ConditionImprovingBenefit atEnd ofYear 5
“Fair” Life Extending Benefit Not Yet Defined
Today’s Participants• Judith Corley-Lay, National Center for Pavement
Preservation, [email protected]• Y. Richard Kim, North Carolina State University,
[email protected]• Colin Franco, Rhode Island Department of
Transportation, [email protected]• Todd Shields, Indiana Department of Transportation,
[email protected]• R. Buzz Powell, National Center for Asphalt
Technology, [email protected]
Get Involved with TRB• Getting involved is free!• Join a Standing Committee (http://bit.ly/2jYRrF6)• Become a Friend of a Committee
(http://bit.ly/TRBcommittees)– Networking opportunities– May provide a path to become a Standing Committee
member– Sponsoring Committees: AHD20, AHD18
• For more information: www.mytrb.org– Create your account– Update your profile
Receiving PDH credits
• Must register as an individual to receive credits (no group credits)
• Credits will be reported two to three business days after the webinar
• You will be able to retrieve your certificate from RCEP within one week of the webinar