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Contractor Quality Control. John Savastio Quality Control Manager Highway Materials, Inc. Purpose and Learning Objectives. Contractor Quality Control
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Contractor Quality Control John Savastio Quality Control Manager Highway Materials, Inc.
Purpose and Learning Objectives Contractor Quality Control This session will explore the Contractor’s responsibilities in controlling the quality of material, from the mix design procedure to pre-pave submittals to testing material during production. The participants will learn: •Tips in developing a mix design to maximize compaction and minimize quality control issues • Requirements in developing the Quality Control Plan (Section 100 of AC) • Control Strip: differences between AC 150/5370-10G and 10H • Required quality control testing in the lab • Familiarization with ERLPM Appendix C Documentation • Field Quality Control – handling of road cores
We’ve Come A Long Way…. • Acceptance based on asphalt content / gradation, air voids • Method based spec.
Implementation of Quality Systems • Testing frequencies • Lines of communication • Equipment maintenance • Calibrations • Proficiency programs
Contractor development of the JMF • Meet Specified Properties • Start by targeting mid-spec. • Utilize resources effectively: “mutual fund” approach • Maximize plant production and efficiency
Laboratory Design vs. Plant Production #200 • Design vs. production • Capability of the Plant • Gradation Variation • Hot Bins • Stockpile • “Degradation” • Volumetric Properties VOIDS VMA #8 SIEVE
JMF to Optimize Compaction • Stability • Correct Amount of Asphalt • Substantial Roller Effort • Effect of Natural Sand- Rounded Particles • Workability • Low / High #200 • Excess Coarse Aggregate
What Are the Requirements? • Section 100 (Item C-100)Contractor Quality Control Program • Complete project quality control requirements • Broad based requirements • Section 401, 403, (404) FAA Specifications • Plant Mix Bituminous Pavements • Detailed quality control requirements for HMA production and testing
Item C-100 Requirements • QC Program Intent • Provide information to assure specification can be met • Provide production of acceptable quality materials; documentation; corrective action • Assure CQC personnel are coordinating with QA personnel throughout the project
Item C-100 • Program Description • Explain to the Owner what the Contractor is going to do to provide the Owner an acceptable project that conforms to all plans and specifications • AND PUT IT IN WRITING!!
Before the Project Begins….. • JMF’s submitted at least 14 days in advance • QC Plan submitted for review at least 14 days in advance
Components of QC Plan • Quality Control Organization • Project Progress Schedule • Submittals Schedule • Inspection Requirements • QC Testing Plan • Documentation of Activities / Report Distribution • Corrective Action
Quality Control Organization Adam Amspacher Raymond Gonzalez PlantTech Field Tech QC Organization for Lancaster Airport Southeast Apron Improvements David Roman Project Manager John Savastio Don Neil QC Manager Paving Manager Jerrod Willow Richard Sonnon Sr. QC Tech Paving Foreman Enough QC Techs to get the Job done at Plant & Field
Quality Control OrganizationAC 150/5370-10G • Program Administrator • Professional Engineer w/1 year experience • Engineer-in-Training w/ 2 years experience • BS Civil Engineering/Technology/Construction with 3 years experience • NICET Level III (Materials/Construction) Technician • NICET Certified w/ 5 years experience
Quality Control OrganizationAC 150/5370-10H • Program Administrator • Professional Engineer w/1 year experience • Engineer-in-Training w/ 2 years experience • NICET Level IV (Materials/Construction) Technician w/ 3 years experience • BS Civil Engineering /Technology/Construction w/ 4 years experience
Quality Control Organization • Program Administrator Duties (CQCPA) • Institute and implement the Quality Control Program • Authority to stop production until material is in compliance with specifications • Reports directly to a principal director of the construction firm
Quality Control Organization • Quality Control Technicians • Engineers • Engineering Technicians • Experienced Craftsman • Certifications Equivalent to NICET Level II • Minimum of 2 years experience in area of expertise
Quality Control Organization • Quality Control Technician Duties • Inspect all materials, construction, plant and equipment for conformance to the specifications • Perform all quality control testing required by the specifications and quality control plan • Assure all materials meet specifications and follow corrective action guidelines when materials do not meet requirements
Inspection Requirements • Field Operation • Quality Control Tests • Density readings and cores results • Inspection of equipment used for placing, finishing & compaction • Plant Operation • Quality of Aggregate • Verify aggregate production/delivery • Mix Control • Verify blending/proportioning • Plant Equipment • Inspect thermocouples, scales, asphalt delivery & mixing chamber
Contractor QC Testing Facility ASTM D 3666 -8.1.3 Equipment Calibrations & Checks -8.1.9 Equipment Calibration, Standardization & Check Records -8.1.12 Test Methods & Procedures
Item C-100 - QC Plan • Item Number • Item Description • Test type • Standard • Frequency • Responsibility • Control Requirements
Item C-100 - Documentation • The contractor is required to maintain current (daily) quality control records • These records must show all inspections results to include conforming and defective or deficient work • Must be legible and signed by the Program Administrator
Item C-100 - Documentation • Daily Inspection Reports • “Factual Evidence of continuous QC Inspection” • Technical specification item # and description • Compliance with approved submittals • Proper storage of materials and equipment • Proper operation of all equipment • Adherence to plans and technical specs • Review of quality control tests • Safety inspections
Item C-100 - Documentation • Daily Test Reports • Review of QC Tests • Technical specification # • Test designation • Location • Date of test • Control requirements • Test results • Causes for rejection • Recommended corrective action • Retests
QC Plan – Corrective Action noticed trend. High voids – Trend – Fine aggregate running clean – Mix adjustments Quarry process change – Change bin pulls or Aggregate % Standardize the procedures you took if it worked. If not, repeat process. Raw gradation/Hot bin Final mix gradation Voids check
Item C-100 • Observations by the Engineer (RPR) • All operations, production, manufacture, shipment or placement, are subject to inspection by the Engineer (RPR) • Observations by the Engineer (RPR) do not relieve the Contractor or performing quality control inspections
Item C-100 • Noncompliance • The Engineer (RPR) will notify the Contractor of noncompliance material at which time the Contractor shall immediately take corrective actions • Where quality control activities do not comply • The Contractor may be required to replace unqualified work or personnel • The contractor may be ordered to stop work
Item C-100 – QC/QA Workshop(Pre-pave Meeting) • Contractor • Producer • Owner • Consultant engineer (RPR) • Assurance Testing Laboratory
Pre-Test Mix Verify mix properties at the plant (gradation, asphalt content, air voids, VMA) and make adjustments if necessary. Test results should be as close to target as possible.
Pre-Test Mix Verifying field properties (workability, ease of compaction, density) is as essential as verifying the mixture properties. Try to place over an area with similar conditions.
Section 401, 403, 601 (404) – Contractor QC Test Strip (Control Strip) Q/C Testing Requirements Control Charts Field Q/C
Construct Test Strip P-401, P 403 AC 150/5370-10G • 300 x 30 ft, 2 passes • Longitudinal joint • ≥3 Random Samples • Plant Mix (P-401 only) • Field Cores - Density • 2 Attempts prior to removal at Contractor’s expense.
Construct Test Strip P-601 AC 150/5370-10G • 300 x 30 ft, 2 passes • Longitudinal joint • 3 Random Samples • Plant Mix: Stability & Air Voids • Field Cores: 3 Mat Density & 3 Joint Density • 2Random Samples -- Plant Mix: Asphalt Content & Gradation
Test Section- Testing CriteriaP-401 & P-601 AC 150/5370-10G • Action Limits (individual measurements) ¾”= +/- 6% Air Voids PWL of the lot ≥ 90 ½” = +/- 6% Mat Density PWL of the lot ≥ 90 3/8”= +/- 6% Joint Density PWL of the lot ≥ 90 #4 = +/- 6% #16 = +/- 5% If Marshall is specified: #50 = +/- 3% Stability & Flow additionally #200 = +/- 2% must have a PWL ≥ 90 A/C = +/- 0.45% VMA = design minimum
Test Section- Testing CriteriaP-403 AC 150/5370-10G • ≥ 3 Sublots Mat Density ≥ 96% Joint Density ≥ 94%
Construct Control Strip P-401, P 403, P-404 AC 150/5370-10H 250 Tons or ½ day’s sublot, whichever is greater 2 lanes with same width and length as production Longitudinal cold joint Same equipment, subgrade as production ≥ 3 Random Samples Plant Mix Field Cores - Density Payment only made for an acceptable control strip.
Control Strip Criteria: P-401, P-404 AC 150/5370-10H Action Limits (individual measurements) - Gradation and Asphalt content - VMA -0.5 Mat & Joint density, Air Voids PWL ≥ 90 PASS If PWL <90, evaluate & act accordingly If PWL <80, cease operations, determine reason If PWL <71, subtract 5% from joint density Pay Factor
Control Strip Criteria: P-403 AC 150/5370-10H • Action Limits - Gradation and Asphalt content - VMA -0.5 Air Voids: ≥ 2%, ≤ 5% Mat Density: ≥ 94 (average of all sublots) Joint Density: ≥ 92 (average of all sublots) Payment only for acceptable control strip
Section 401 – Contractor QC Testing Laboratory Joint Use by Contractor and Engineer Engineer has priority use of necessary equipment Minimum of 150 ft2 with a ceiling height of 7.5feet Adequate lighting Equipment properly maintained
P401, 403 Table 1 AC 150/5370-10H Asphalt Design Criteria Test Property Value Test Method Number of blows or gyrations [75] Air voids (%) 3.5 ASTM D3203 Percent VMA minimum See Table 2 ASTM D6995 Tensile Strength Ratio (TSR) ≥ 80 at a saturation of 70-80% ASTM D4867 Stability OUT Flow OUT Asphalt Pavement Analyzer (APA) Less than 10 mm @ 4000 passes AASHTO T340 at 250 psi hose pressure at 64°C test temperature
Asphalt Pavement Analyzer (APA) AC 150/5370-10H Less than 10 mm @ 4000 passes AASHTO T340 at 250 psi hose pressure at 64°C test temperature
Plant QC Requirements Asphalt Content Twice per lot Gradation Twice per lot
Section 7.1: Asphalt Content Extraction – ASTM D 2172 Ignition – ASTM D 6307 Nuclear method– ASTM D 4125
Section 7.2: Gradation Analysis Gradation Cold Feed Composite Hot Bins Belt Composite Sample These provide support for controlling the process in addition to the HMA mixture gradations
Section 7.2.4: Aggregate Moisture Aggregate moisture Once per lot Mix moisture Once per lot <0.5%