Review 2014 HMA test data Review Changes to CS 409 (2015) Discuss 2015 Bit DEL changes Protocol for Reheating HMA Samples Verification Data 2014 /

Transcription

1 Review 2014 HMA test data Review Changes to CS 409 (2015) Discuss 2015 Bit DEL changes Protocol for Reheating HMA Samples Verification Data 2014 / 2015

2 40 different JMF s 14 had PWL of 90% or greater 26 needed Design rework 12 different Producers 19 different plants VMA PWL average was 83%

3 Total Lots % payment 528 (88%) 97% payment 35 (6%) R&R 26 Lots (4%) 13 Removed and Replaced 8 LIP (50%) payment 3 LIP (0%) payment 2 LIP (100%) payment

4 High AC 2 Low AC 5 High #200 0 Low #200 0 High Air voids 28 Low Air voids 34 Low Density 11 Average Density 94.3

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6 (b)1. General Requirements Include minimum 90% manufactured sand in the fine aggregate portion of the bituminous mixture. (e) 1. Virgin Material Mixtures...Design Va on 25mm Rich Bottom mixes at 2.5% at Ndes through the addition of AC to an approved PTC 25mm design

7 At the end of the production season a copy of the Bit-DEL QC and Acceptance software shall be transferred electronically to the Commission s Materials Supervisor and become the property of the Commission.

8 (e) 1.e.1 If the average loose material sample test results fail to meet 100% payment values listed in Table I on 3 consecutive production days for AC percentage, No. 200 sieve gradation, Va, or the minimum VMA tolerance noted below, cease production of the JMF

9 .When the G mm value varies by or more from the previous test or from the JMF value for three consecutive tests, cease production of the JMF. Investigate the reason for the deviation, provide a written explanation for the deviation as well as proposed corrective action to the Commissions Material s Supervisor before continuing production.

10 Producers volumeters used in HMA testing shall be assigned a specific identification number. The volumeter identification number must be engraved or stamped into the base and lid of each volumeter. Anytime a volumeter is used for PTC mix design or acceptance testing purposes, any recalibration of the volumeter must be witnessed by a Commission Representative.

11 Acceptance by certification is appropriate for the following conditions or applications: Production of 150 tons or less Scratch or leveling course material Other mixtures, conditions or applications as approved by the Representative 2a General

12 2.b Certification of Mixture 2.c Maintaining Approval to Certify Mixtures. The PTC may suspend a plant s approval to certify mixtures if QC testing is not performed according to the producer s QC Plan, mixtures are not produced according to Bulletin 27 or a mixture cannot be certified on 2 consecutive production days. 2.d Density Acceptance. Density for certified material will be accepted by section 409.3(j)2 or 409.3(j)3

13 (c) Bituminous Mixing Plant. ELIMINATED >>>>> Location of bituminous mixing plants must be within 40 miles or one hour travel time for delivery vehicles.

14 Use steel-wheel, pneumatic-tire, vibratory, or oscillating rollers as specified or allowed in Section (c) 3 or 4. Operate rollers according to manufacturer s recommendations. Use vibratory and oscillating rollers with separate controls for frequency and amplitude. Eliminated >> Three-Wheel Power Rollers.

15 Also apply a tack coat to the base or binder course of newly constructed pavements when in the opinion of the Representative, the surface is not satisfactory for direct placement of paving. Provide the Representative with the anticipated shift tonnage for placement.

16 When a widener is used to place the HMA mixture, the loose material sample may be obtained from the hopper of the widener.

17 The Inspector will complete PTC Form SB 413 with the necessary information and place the form in a water tight envelope (provided by the producer) inside a container of sufficient strength to prevent samples from being damaged during transport. If the samples show any evidence of their security being compromised, the Commission may reject them for testing, suspend paving operations and require additional samples to be taken for acceptance.

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19 Reduce the sample according to AASHTO R47 Section 7 Mechanical Splitter Method A 7.1, utilizing a quick funnel insert into appropriate sizes for testing asphalt content/gradation (percent passing the No. 200 sieve), maximum specific gravity, and two gyratory specimens.

20 A lot will be 1,500 tons or portion thereof, with two equal sublots (n=2). Each sublot will have 3 loose box samples and 3 pavement cores collected according to PTM 1, PTM 729 and PTM 746 in the presence of the Inspector. Each lot will be specific to a JMF and each HMA producing plant, if multiple plants are used. Each lot will be specific to each paving crew if more than one crew is used.

21 At locations selected by the Representative and in the presence of the Representative, drill a minimum of three 6-inch diameter cores from the area of pattern segregation marking the samples as S (Segregated) and a minimum of three cores from the pavement representing a non-segregated area marking the samples NS (Non-Segregated). The Representative will transport the cores to the producer s laboratory and transfer custody of the cores to the Commission s plant inspector.

22 ..If samples are damaged, immediately notify the Inspector. If directed by the Inspector, obtain replacement samples from within 12 of the original sample location. The Inspector will complete the necessary information on PTC Form RC 426 and place the form in a water tight envelope (provided by the producer) inside the same container If the samples show any evidence of their security being compromised, the Commission may reject them for testing, suspend paving operations and require additional samples to be taken for acceptance.

23 ..For quality control purposes, a maximum of one pavement core per shift may be obtained. No cores may be taken by the Contractor after the acceptance cores are obtained.

24 1.a General..Before placing abutting lanes, paint the entire face of the joint with a uniform coating of bituminous material, the PG-Binder used in the pavement course or PG Seal all completed wearing surface longitudinal and transverse joints with rubberized joint sealing material meeting ASTM D6690-Type I from a manufacturer in Bulletin 15 as specified in Section 705.4(c). The sealing band must be 4 to 6 in width evenly applied across the joint.

25 PROGRESS. NOT PERFECTION!!!!

26 PTC Bit DEL 2015-A Revisions

27 2014 Bit DEL

28 2015 Bit DEL

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34 During the 2014 construction season some of our HMA producers questioned the practice of reheating the loose mixture samples taken from the roadway for acceptance. The real issue being the Air Void replication of the mixture. However the issue is greater than just air voids. It s really about mixture sampling, how the mixture is reheated, mixture conditioning, how the samples are split, and then gyrated.

35 It became apparent that how the loose HMA mixture, from the roadway, was being handled in the labs when reheated for acceptance testing, varied between each producer and sometimes between the different HMA testing labs/ plant locations from a particular HMA producer. A review of HMA specifications from the 22 states, that use roadway loose samples, for acceptance testing, was done. Attention was given to the reheating protocol that each of the states mandated. Again some variations in protocol was noted but many of the practices were the similar. Also considered was a report/study by the National Center for Asphalt Technology NCAT at Auburn University entitled Effects of Re-heating and Compaction Temperature on Hot-Mix Asphalt Volumetrics.

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38 2. c. Mixture Acceptance Sample Testing. The HMA loose samples should be at room temperature prior to commencement of the testing procedure. The HMA technician shall remove the loose mix sample from the cardboard box and place into a suitable pan for reheating. The technician shall reheat the three loose samples for each sub-lot using a forced draft oven, thermostatically controlled, calibrated and capable of maintaining any desired temperature setting from room temperature to 349 F + 3 F. The pan containing the mixture may be covered to assist in the reheating process. The maximum oven temperature shall be the maximum mixture temperature for the PG binder of the mixture being tested as specified in Bulletin 25, page 1. At no time during the reheating process should the temperature of the sample exceed the PG binder maximum temperature. If different PG binder mixtures are being reheated in the same oven, at the same time, use the lowest maximum temperature of the PG binders being tested as specified in Bulletin 25, as the maximum temperature set point for the oven. When the mixture is workable, blend the three samples into one homogeneous sample. Split the sample according to AASHTO R47, section 7 Mechanical splitter method A 7.1, utilizing a quick funnel insert into appropriate sizes for testing asphalt content / gradation, (percent passing No. 200 sieve), maximum specific gravity and two gyratory specimens. Place the loose sample material to be used for the Gmb plugs back into the oven to be heated to the compaction temperature listed on the supplier s bill of lading. Stir the mixture at the midpoint of the reheating process to ensure even heating of the mix. The pan containing the mixture may be covered to assist in the reheating process. The test results of the loose material will be used as the criteria for payment according to Table I. All acceptance testing shall be performed according to the AASHTO and Bulletin 27 procedures as specified.

39 Bulletin 25, page 1 Oven Maximum Temperature Set Point Guide Line

40 2014 (114) / 2015 (50) 25m 19 / 12 19mm 47 / mm 32 / mm 16 / 7

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42 2014 Mix Verifications 2015 Mix Verifications 25mm 19 mixes verified 25mm 12 mixes verified to date 25mm 2014 Average Variation Between Producer and Mobile Lab Variation Spread Min Variation Max Variation 25mm 2015 Average Variation Between Producer and Mobile Lab Variation Spread Min Variation Max Variation 1 1/ / / / / / / / # # # # # # # # # # # # # # Asphalt Asphalt Gmm Gmm Voids Voids VMA VMA

43 19mm 47 mixes verified 19mm 16 mixes verified to date 19mm 2014 Variation Spread 19mm 2015 Variation Spread Average Variation Between Producer and Mobile Lab Min Variation Max Variation Average Variation Between Producer and Mobile Lab Min Variation Max Variation / / / / / / # # # # # # # # # # # # # # Asphalt Asphalt Gmm Gmm Voids Voids VMA VMA

44 12.5mm 32 mixes verified 12.5mm 15 mixes verified to date 12.5mm 2014 Average Variation Between Producer and Mobile Lab Variation Spread Min Variation Max Variation 12.5mm 2015 Average Variation Between Producer and Mobile Lab Variation Spread Min Variation Max Variation 3/ / / / / / # # # # # # # # # # # # # # Asphalt Asphalt Gmm Gmm Voids Voids VMA VMA

45 9.5mm 16 mixes verified 9.5mm 7 mixes verified 9.5mm 2014 Variation Spread 9.5mm 2015 Variation Spread Average Variation Between Producer and Mobile Lab Min Variation Max Variation Average Variation Between Producer and Mobile Lab Min Variation Max Variation 1/ / / / # # # # # # # # # # # # # # Asphalt Asphalt Gmm Gmm Voids Voids VMA VMA

46 East (Mp & A20 A131) Steve Havrilla Central (Mp Mp 300) Brian Wible West (Mp 0 - Mp142) Chris Forry cforry@paturnpike.com Brian Paroda (Materials Lab) bparoda@paturnpike.com

47 TERRY D. DREHER (office) (cell)