NCAUPG Annual Meeting Minutes
October 22 - 23, 1997

 P.O. Box 2382
West Lafayette, IN 47906
Telephone:  (765) 463-2317 x226
Fax:  (765) 497-2402

 

Minutes
North Central Asphalt User/Producer Group
Hilton-Airport
Kansas City. Missouri
October 22 - 23, 1997

Minutes provided by Dick Ingberg

Session Moderator Wayne F. Murphy, MNDOT

Welcome: Charles Boyd, FHWA

Welcome from FHWA and as one of the Field SUPERPAVE Technical Delivery Team to implement SUPERPAVE. A key initiative for FHWA is to work closer with the UPG’s. We want work together to implement SUPERPAVE and other asphalt related initiatives.. Fourteen states and two provinces met in July, 1991 in Chicago to form the North Central Asphalt User/Producer Group. Fifteen attended and decided to verify and implement SP Binder and Mixture and meet twice a year to accomplish that goal. Although we have accomplished much, there are still several things yet to do. You have a revised set of goals and a re-alignment of the sub-groups, the North and the South, with 12 states and two provinces. The five goals are:

I. Form and support Local Agency/Industry Groups;
II. Benefits/Criteria for Pavement Performance;
III. Review, Evaluate and Refine Uniform SP-PG Binder, Aggregate and Mixture Design Specs;
IV. Review, Evaluate and Refine QC/QA Specifications
V. Monitor Constructability Issues.

I would like to talk about a few items while I’m here. Westrack: There have been some failures in Reno We have a team of experts that went to Reno to investigate the project. There will be a final report out on it soon. The test sections that failed were experimental and would not have been selected for pavements in real life. Keep this in mind when discussing this project.

The existing state/industry partnership has been beneficial in implementing the binder specs. which took place with few problems. We need to do much more training of technicians and field personnel to overcome construction type difficulties. Each state has to develop QC/QA specifications. We need to pursue training and evaluation of each area or region for uniformity. Last week FHWA met with the states in Region 7 and they made a commitment to a uniform technician certification program. All the state and contractor personnel will not have to be re-trained when contractors cross state lines.You should work closely with the SP Center and develop a consensus of what SP, state and industry needs are.

We would like a show our appreciation to Dick Ingberg as the Regional Engineer for the Long Term Pavement Performance Program and as Secretary for the North Central Asphalt User/ Producer Group. He was able to do a number of things for this group and was involved in its formation . We will miss you in this role. Because of his retirement, funding options to continue Dick’s services are needed. An estimated operating cost of $ 13,500 is anticipated with projected income of $ 7,500, shortfall of $ 6,000. We will try again to get some funding through FHWA to help in this time of need. FHWA is committed to providing resources to resolve technical issues and to improve the quality and cost effectiveness of HMA pavements.

Keep up the good work!

What Have We Learned About SUPERPAVE Panel Discussion: Gerry Huber, Heritage Research, IN/Rick Smutzer for Don Lucas, INDOT/Haleem Tahir, AASHTO/John D’Angelo, FHWA

Many states are gaining experience with the implementation of SP with some talk about problems or rumors of problems. This next panel will make presentations about some of supposed and otherwise problems associated with their and others experience in implementing SP. There will be an open discussion period . Let’s not do the same things that caused problems in other states as they implemented SP.

Gerry Huber

They started out with Gerry because he was the least bearer of bad news. SP in Indiana in 1997. I will try to present a picture of implementation as they have occurred in Indiana. What have we done. We started on a Pilot SPS-9 project near West Lafayette in 1992. We had a geometric progression of projects of 1, 3, 9, 16, 45, 97. These are all on principle arterials from 1,000,000 to 10,000,000 ESAL’s

Mainline Shoulders
Binder Grades 58-28 12 40
64-22 22 3
Modified 64-28 9 1
70-22 1
70-28 2
70-34 2

We have made a major change in our surface mix. Indiana uses washed aggregates , so dust is low. SUPERPAVE required adding more fines. SP surface mixes use less sand and have slightly more binder ( 0.2% ). Intermediate and base mixes are little changed except that more dust is needed. We have no rutting on the mainline pavements although the shoulders show some rutting during construction, but these are isolated. We had used 500,000 ESAL’s for design on shoulders, but now use 2,000,000.

On I-74 we had a calamity with both rutting and flushing. When we investigated the project we found a high asphalt content, incorrect aggregate bulk specific gravity and moisture in the mix being placed on the roadway. We placed this same mix previously in the other lane with the same traffic and experienced no problems. Design was 9,000,000 ESAL’s for 7.5 years and 20,000,000 for 15 years. The Design Binder Grade- selection of grade and bumping. The binder grade design is a tool to make a binder decision; too low a grade produces flushing. After the I-74 project started flushing, a review was initiated. Rumors were circulating of flushing occurring everywhere. In the end, eight projects were identified as having flushing. Initial investigation showed these to be minor or localized, i.e a bad load. Such occurrences happen, regardless of the design method used. There is no indication that SUPERPAVE designs lead to flushing. A final report will be available early in 1998.

So what is happening today in Indiana. We have re-drafted our standard specifications. Effective January, 1998, there will be no more Marshall mix designs for Indiana DOT, only SUPERPAVE. All pavements in Indiana will have density based on percent of Rice. We will have full Superpave implementation in 1998. This will trickle down to the local level. The City of Indianapolis will be all SP in two years as well. This will trickle down to the local level.

In Indiana, SUPERPAVE implementation has been successful with limited problems. Indiana and industry are pleased with Superpave. The shortcomings will be addressed.

Rick Smutzer

We had a calamity in 12 miles of I-74 with flushing. The first five miles constructed earlier had no problems. It was a mill and fill 1" or 25 mm surface mix with a five year design life. The programming of projects in Indiana were feast or famine. So in order to balance out this load , we shifted the design life to distribute contracts to even out the annual workload. Therefore, this project was to hold for five years before a more major rehabilitation. With a design traffic of 9.7 million ESAL’s for 6-8 year design life , we missed the 10M to 30 m ESAL design criteria. The lower criteria specs were used with a 9.5mm aggregate for a 25mm laydown thickness. The job was constructed in two phases. The first phase , prior to Memorial Day, did the passing lanes. After Memorial Day, and as you remember the race was postponed due to heavy rainfall. Well, it also rained on the aggregate stockpiles for this project. The pavements that were exposed to the sun flushed, whereas the pavements under the underpasses did not flush. Exposure to the sun( solar heating) along with excessive moisture and asphalt combined cause the pavement to rut and flush. The effective asphalt in the mixture was very high ( greater than 6.6% ).

They had recorded very high moisture content on the belt samples going into the drum. They did not get moisture samples on the bituminous mixture. The combination of being designed for low ESAL’s, low compactive effort, high asphalt content, and 5-6% passing the #20 sieve and more than 50% of this passing the # 325 sieve (which works as effective asphalt or an asphalt extender), warm and humid weather before and after construction lead to flushing in this pavement. On Phase 1 we were at 99% of target density ;in phase 2 104.5% of target density . There was just too much fluid in the mix. There will be no more mix design lives under 15 years for traffic in Indiana in the future.

John D’Angelo

John opened with a picture of a crew looking at the performance of the test sections at Westrack to see what was happening. WesTrack, FHWA’s hot-mix asphalt (HMA) performance-related specification test facility in Nevada, passed another significant milestone in April as it completed a full year of traffiking. Although much of the test data to that point had been expected, some of the most recent results have been surprising. At the 1-year point some 2.7 million 80 kN (18,000-lb) equivalent single axle loads (ESAL) had been applied to the tracks test sections; the heavy loading had produced rutting in most of the track’s 26 test sections and fatigue cracking in many. Ten sections had rutted 25 mm or more or showed severe fatigue cracking and were replaced in late June. The new sections were constructed with a different aggregate than had been employed in the original 26 sections, to provide further data towards the project’s objectives of performance-related specifications development and Superpave validation.

The new experiment at the track is designed around the relatively coarse Superpave gradation of a well-crushed, quarried stone. The design mix met all Superpave requirements for binder and aggregate properties and volumetrics. Sections were placed, as in the original experimental sections, with low, optimum, and high asphalt content and low, optimum, and high in-place air voids. Quality control testing was conducted behind the paver during construction and data indicates the mixes had the required volumetric properties and the targeted gradation and asphalt contents. The performance of the sections has been surprising, with the several new sections exhibiting significant permanent deformation within the first few days of traffiking.

Coarse-graded Superpave mixes similar to the ones at WesTrack have been placed on many pavements around the country. Most have performed well in high traffic and hot temperature environments and have not had the failures seen at WesTrack. It is not clear whether the early failures can be attributed to the high rates of loading or to some combination of materials and/or construction that has produced a vulnerable pavement.

The FHWA is moving quickly to address the questions at WesTrack. The agency has assembled an independent team of national experts to look into all aspects of the design and construction of the new sections and to report on its findings by mid-September. The results of the investigation may lead to further refinement of Superpave criteria for coarse-graded mixtures----or to new views on the relation of accelerated pavement testing results to real-world pavement performance.

For more information contact:
Terry Mitchell at 703-285-2434
e-mail terry.mitchell@fhwa.dot.gov or

John D’Angelo at 202-366-0121
e-mail john.d’angelo@fhwa.dot.gov

Haleem Tahir

Where are we? Our sources of information come from the state DOT’s . They tell us where they are. The Lead States, the Sub-Committee on Construction , the Sub-Committee on Materials and the FHWA are key players in the implementation of SUPERPAVE. According to an article published in FOCUS, more than half the DOT’s have implemented SP. We are working with the local governments the SP implementation issues. The survey just completed tells us that 44 states will be using Level 1 mix design by 2000.

There is general consensus that uniform implementation of SP is needed:

By way of personal experience, I have used the aggregate specification in MD 10-12 years before SP. Twelve years ago the specs were the same as SHRP and SP recommended. We also used to have L.A. abrasion, which we don’t have anymore.. We had no rutting problems since we adopted these specs and never saw flushing if everything was done right.

Another problem is aggregate availability along with the cost of aggregate. Different states come up with divergent conclusions:

The FAA limit of 45 is a problem. You must use manufactured sand to obtain. 45 is the question is still being argued.

Details of the gyratory:

VMA is another area of debate- Should there be an upper limit on VMA in addition to the lower limit?

Strength Test- Consensus is that we need one; They are working on it.

Models Contract- Old AASHTO procedures many feel are not adequate. The research is on-going on this.

PAV Issue- The contract manager at NCHRP is looking for a rational answer.

Models and Performance Analysis-

Laboratory Equipment- Is very sensitive and need to find out how to keep it in calibration. John D’ Angelo and his people are working on this.

Field Laydown- Segregation is a problem with the coarser SP mixes. Find out how to avoid segregation.

Compaction: One out of three projects are having compaction problems. They either do not know how to compact or have some other problem. Expertise in the area of breakdown rollers, closeness to the paver, elevated mix temperatures, no pneumatic rollers and guidelines for the technicians or operators to follow the rules.

Quality Control/Quality Assurance-Use the basic framework that was developed under NCHRP 9-7 can be used for SP.

Another area you may be interested in is the NCHRP Pooled Funds Study. The basic concern is "What is being done, who is working on it and who are all the players?" There is no consolidated list of research or resolutions to problems.

Communications Gap- There is a communications or mis-communications gap. We try to keep 52 Materials Engineers’ informed as to what is going on. We are trying to keep them informed, however we never seem to communicate entirely.

Future of Superpave- Is not a perfect system, but, it is the best thing that has come along in 30 years. SP has some wrinkles, gaps, and problems.

We are working on the models and performance analysis . They are all on the fast-track and will be done very quickly. We are striving for a perfect system and I am sure it will be improved further in 20 years.

One area we are deficient is in the a Central Technical Resource Center. Somewhere the experts can consult literature on asphalt pavements, a data center. A place where we can put information on our problems and solutions to these problems in one place. A Central Data Center.

Local Government Training in SP- Hats off to Indiana. They are way ahead of the curve. Yes, SUPERPAVE will be implemented in my lifetime.

Question and Answer Period

Tom Bryan stated that " The problem in the field is how to measure moisture in the mix. There is no easy or quick test. Maybe we should use a microwave to test, maybe we have to cut back on production at the plant"

Gerry Huber, " The question is where do you sample for moisture content? Do you measure off the washer, off the belt, at the gyratory, at the discharge chute, after the paver?"

A study was done by there Heritage Research Group to look at the effect of moisture. Moisture in the mix softened it. We could measure the difference with the shear tester.

Gerry Reinke, Mathy. Less than one-quarter % moisture on sample High slag content? Huber replied Indiana has no limits on slag content. This mix had 50% coarse aggregate as blast furnace slag.

Gerry said they used a gallon pail which was sealed. Weighed the sealed can, losing moisture etc.- measuring and determining the effects of moisture. Moisture affects some mixes more them others.. Some asphalts soften in the presence of moisture. This has an effect on stiffness depending on the AC binder.

What were the differences between I-74 in Indiana and Westrack?

The VMA on I-74 was 2% above mix; minimum. Why? Logistics of the project, materials and transportation. It was easier to add AC. It had 74.9% VFA where 75% is the limit in mix design.

Jim Campbell, MODOT.  Haleem’s comment about the aggregate problem in MO. I would like to defend the State. We do have some marginal quality limestone aggregate in the northern half of the state. Over the entire state, so far, we have mixes of 100 percent crushed stone which meet SUPERPAVE criteria. There are approximately 160-170 SUPERPAVE mixes which comply with SUPERPAVE requirements by adding up to 20-25 percent porphyry ( trap-rock ), steel slag, crushed gravel or a metallic chat.

Phil Blankenship , Koch talked about AC grades, called grade bumping for increased traffic loadings

SUMMARY

Wayne Murphy asked Gerry Huber to summarize an excellent discussion.:

Haleem

Binder Update: Rick Smutzer, INDOT/April Swanson, AMOCO

Binder implementation seems to be going well nationwide. PP-26 Provisional Specfication developed by the NCAUPG truly played a part in success. In the Midwest all highway agencies except Illinois have implemented the Binder specifications. On the industry side, " How well is it going? " April Swanson will tell you in her presentation:

Remember the Basics: April Swanson, AMOCO

Implementation of PG binders in 1997 in the NCAUPG area has been very successful from the suppliers point of view. This was a direct consequence of the work done up front by NCAUPG members. Although a few problems were encountered and some of the binder test need improvement, the Superpave specifications are a powerful tool of characterizing low-temperature and aged properties of asphalts.

How have PG binders changed? The absolute viscosity is a very good predictor of PG grade because it is measured at a temperature that is close to the temperature of the original DSR test. Minimum viscosity’s are very consistent for a given grade:

PG 70 4000 poise minimum
PG 64 1800 poise minimum
PG 58 800 poise minimum
PG 52 400 poise minimum

There is no maximum limit on an original DSR test result, so the viscosity may be different of PG grades from different suppliers. Comparison of high or low PG grade with a penetration grade is not straightforward across different suppliers because test temperatures are different for penetration and PG binder tests.

Rutting is still mainly influenced by mixture properties with PG binders. To get the best result, the high temperature PG grade should be increased only after mixture properties are good. Low temperature cracking is controlled by the binder and should be improved by decreasing the low PG grade.

Progress has been made in FHWA on the direct tension test, which is now showing better agreement with bending beam results for ranking low temperature properties of asphalts. It is not known whether current fatigue tests for PG binders are appropriate. Reproducibility is very poor for dynamic shear rheometer results on residue from the pressure aging vessel. The Asphalt Institute members currently have a study underway to look at sources of test variability.

Overall, the first year of PG binders was very successful in the NCAUPG region.

Remember the Basics, Implementation has been a roaring success. We have accomplished a lot by working together!

Wisconsin Round Robin Test Results: Tom Brokaw, WIDOT

Wisconsin had a certification acceptance plan with split-sampling. As they moved to PG binder implementation we were concerned with the repeatability of tolerances for the new test. It was with this in mind that we sent out samples on a round robin testing program to suppliers and put together the results. Later on MN and IA got their suppliers involved In 1998 we came up with the Tri-State Certification Method. Using the same program made life easier for all of us. We now can share data and eliminate duplication of effort for the asphalt suppliers and the states. The process went pretty smooth. We have conducted five round- robins to date and reports are out on all the data. The coefficient of variation of the suppliers is plus or minus one standard deviation( throw out all outliers outside three standard deviations). Although there were very few outliers there were very significant drops in the coefficient. Mass loss has a very high coefficient of variation. AASHTO also looked at this in detail. Through improved technical transfer, our testing is ready and the numbers are dropping as long as we follow procedures better we will continue to lower our variability. We will be building these tolerances into our QC/QA program .

Open discussion:

Gerry Reinke stated there was a small amount of material being lost, .02 to .027 mass loss, including the weight of the bottle

Mixture Update: John Isackson, MNDOT

In 1997 Minnesota had five Superpave projects. There is a handout on our experience with Superpave.

  1. The project on TH 60 at Madelia. This was a fine-graded mixture designed with an N initial = 88.9. In the field N initial was 90-91 and the mixture was very tender. It was difficult to achieve proper density with the high n initial mixture which was too tender.
  2. Interstate 90 near Winona. This was a coarse-graded that passed all the design criteria in the laboratory. The problem was low N initial of 83-85 during production. In most instances, 22 roller passes failed to achieve 8% air voids. It was difficult to achieve proper density with a low N initial mixture which was too harsh. The good thing about this project was that one segment of pavement utilized an un-modified PG 58-34.
  3. The TH 23 at St Cloud. MNDOT successfully used a 3% air void design for the non-wear Superpave instead of a 4% design. The inconsistency of the design air voids was a problem.
  4. MNRoad. Two Superpave mixtures were placed in 225’ pavement sections. One was a 19.0 mm coarse mixture and the other one was a 12.5 mm restricted zone mixture. The quantities were too small to make changes in the field. The coarse mixture had high design voids,
  5. Interstate 494 at Eagan. The night paving during September presented many challenges due to the cool temperatures. This coarse mixture had a 60% failure of N maximum.

MNDOT learned some important things about Superpave mixtures as follows:

  1. The lift thickness should be increased to four times the nominal maximum aggregate size to achieve proper density.
  2. N initial = 86-87 may be a happy medium for mix design .Tenderness problems are minimized and density can still be achieved.
  3. The use of a 19.0 mm nominal maximum aggregate size should be minimized or eliminated for wear courses due to density and ride considerations.
  4. It is a good idea to use a 3% air void design for non-wear to minimize mat permeability.
  5. Un-modified PG 58-34 has a lot of potential for future use in Minnesota because it is less expensive than polymer modified PG 58-34.

Day 2 Moderator Dave Holt, MNAPA

At our last meeting in Madison, WI, the Management Committee met to go over the original goals and objectives of the group. One of the first questions that we asked ourselves " Is there still a need for this organization?" As the answer to this question was positive, we went to work on a revised set of goals and objectives for the future. We also looked at a succession plan for the Co-Chairs on the Executive Committee as well as reducing the number of sub-groups from three to two. The philosophy of the group remained unchanged. Don Jordison had the task of surveying the states and provinces.

Goal I. Local Agency/Industry Groups: Don Jordison, IAAPA

Don reported responses to the user producer questionnaire from eleven states. Results were summarized along with that one state and one province were received during the meeting.

One of the goals of the UPG was to encourage each state and province to have a working group. We have accomplished that. There were seven that had formed prior to 1993. Six more have come on board in the last couple of years. The key reasons for forming were to improve the quality of asphalts pavements, resolve the PG binder implementation issues, implement the SP mixture and pilot SPS projects review.. Earlier groups formed to address quality and performance issues; i. e. -Raveling; Segregation; and less frequently, deformation of asphalt surfaces. Project process control and an understanding of volumetrics was lacking. Each group reported the local group with varying names was a joint agency / industry initiative. Participation of the other groups/ agencies varied, but the trend is to expand committees as outside expertise is needed

The three main goals are summarized:

The last thing they mentioned was to keep these goals in mind and look for future areas to solve problems as we get beyond SP and find out how other things affect performance.

SUPERPAVE Schedule:

GOAL II. Benefits/Criteria for Pavement Performance: Rick Smutzer, INDOT

One of the questions brought up at the Management Committee meeting in Madison was "How to market SUPERPAVE Implementation?, How do we measure the cost benefits ?" Rick Smutzer set out to develop the criteria so that we could quantify the benefits of implementing SUPERPAVE. Gerry Huber is working with Rick to work on three basic goals:

When we started looking at projects to compare performance , we had to define the cycle period , the type of traffic. We chose to look at our warranty projects where the period was five years. and high volume Interstate routes. We typically get 7-10 years on the Interstate.

We then asked ourselves, "What do we really want?" Do we want ride quality?, 120 inches per mile, rutting less than 3/8 , and friction resistance. over 35. On high volume mixes , we expect 35, with no section under 25. We wanted ballpark criteria.

We also looked at cracking. In full depth we a wanted no cracking in 5 years. We are talking about significant cracking where maintenance has to come in to repair the crack. We cannot eliminate reflective cracking. Any longitudinal cracks, the contractor has to maintain at his own expense for five years. Other distress items are potholing and raveling. We use initial annual surveys to track performance .

Gerry Huber gave some results on I-65 on a 330’ section rutting was 3mm to 4mm depth. Rut is measured every 6 inches.with ultrasonic sensors. In 1992 SUPERPAVE did not exist. We constructed five pilot projects, three n WI, one in MD, and one in IN. We have five years of experience and data on these projects. (Note there is also LTPP data on these projects as well as the materials and criteria they were constructed to.) I-65 has 40,000 AADT four lanes with 30% trucks.. It is rural Interstate. We did not have N design We used 100 whereas the present criteria would be 109. The fine aggregate angularity was not well defined, however we would meet the current criteria of 45 as our results are 47. We used an AC-20 which is the same as PG 64-22 as expected. It is one and one half miles long over JRCP pcc pavement . It was a straight overlay 25mm.. Looking at 100 meter pieces the distribution of rutting averages 3-4 mm with a maximum of five. The next condition survey will be done in 1997. We would like each agency to bring their data to the next meeting to look at. You will need to define exactly what you are doing.

GOAL III. Review, Evaluate and Refine Uniform SP-PG Binder, Aggregate and Mixture Design Specs: Becky McDaniel, SP Center

The region needs to synthesize the Binder, Mixture and Project Specific Design Data in order to know what is happening with SUPERPAVE implementation and how the specifications are used. We want to know specifically what is happening on each project. AASHTO passed a resolution urging the states to implement the specifications without modification. If the SUPERPAVE specifications are not followed, the mixtures should not be called SUPERPAVE. The Lead State Team is working on defining what constitutes a " substantial modification " and what the unchangeable core of SUPERPAVE is. Changes in the specifications proposed to AASHTO are not official until balloted and approved by AASHTO. The SUPERPAVE newsletter, Website and meeting minutes can help you stay informed. The NCAUPG is in a good position to synthesize what is happening with Superpave from most or all of groups active in the field because we have good representation on those groups - the ETG’s, TWG, Superpave Centers, National Asphalt User/Producer Group, Superpave Extended Delivery Team, Lead State Team and others.

Binder Issues

Some of the issues being addressed by the Binder Expert Task Group includes the the loading time in the BBR, the direct tension testing equipment, the effect of the binder on mix fatigue, alternatives to the PAV and RTFO and tests for modified binders.

Mixture Issues:

The Mixture ETG is looking at changing the definition of flat and elongated particles, fine aggregate angularity (FAA) , a strength test, N design refinement and testing new gyratory compactors coming on the market.

Project Specific Data:

The Asphalt Institute agreed to collect project level data in 1996, but is not planning to do so in the future. A coordinated approach is needed tyo allow sharing data across regions. The Lead State Team has a subgroup working on developing a plan for data collection and the NCAUPG should adopt the Lead State plan. Chuck Boyd, Tom Bryan and Ken Archuleta from FHWA and I are involved in developing a data collection form. We are working with Gary Henderson for funding and the adoption of a format that can be shared nationally to collect relevant data so that we can find out what items are critical to performance.

Questions and Comments:

Jim Campbell posed a question "Is grade bumping in conflict with AASHTO resolution?" Grade bumping is allowed under Superpave; there is some flexibility in binder grade selection that is built into the Superpave system. The AASHTO resolution applies more to changing criteria or test methods.

What about the nine gyratory compactors coming on the market?

Has the protocol been established for approving these new compactors?

The Centers worked with the Mixture Expert Task Group to develop a protocol for testing the new compactors. Bob McGinnis at the South Central Superpave Center in Austin, Texas is the only one testing new gyratorys. He has at least three under evaluation. The manufacturers have to pay for testing. There will be an AASHTO protocol for testing to evaluate new gyratory compactors. The protocol is available on the South Central Superpave Center’s website.

Jim Campbell asked about the data collected last winter. What are the tolerances in the volumetrics plus or minus one percent on the voids and VMA?. They are developing a generic QC/QA plan based on NCHRP 9-7. MN is in the process of evaluating data. They are not using the same test procedure. Measuring Bulk specific gravity is very important. Once we get one approved , how does the process move forward? The data belongs to the compactor manufacturer since they pay for the testing. The manufacturers, then, will distribute the data on their own compactor(s).

The Superpave Center Website is at http://bridge.ecn.purdue.edu/~spave/

E-mail is at rsmcdani@ecn.purdue.edu

GOAL IV. Review, Evaluate and Refine QC/QA: John Volker, WIDOT

What Wisconsin uses , what NCHRP 9-7 uses, what the NCAUPG states and provinces use for process control and quality assurance are all over the place. Each QC/QA process has been developed with the industry in each state independently of other states. In the 1960s and the 70’s the state used the Marshall Method of Testing with penetration graded asphalt and WISDOT mix designs. In the 1980’s WI was having problems on rehabilitation projects with rutting of the hot mix asphalt pavements caused by dramatic changes in traffic loadings. This lead to a directive to the industry to eliminate rutting which lead to the contractors doing the mix designs. In the 1990’s, partnerships were developed with the contractors to develop a Product Quality Management Program, which resulted in the development of a Technician Certification Program and new hot mix asphalt specs, (SMA and Superpave). By the year 2000 they will have lab accreditation and qualifications Agency " verification" testing (CFR Chapter 23) and a Field Testing Program for new HMA products. Tom Bryan stated that the AASHTO Sub-committee on Highways Accreditation is complete with the exception of MN, WI, and RI, but, they are close to it.

Wisconsin Product quality for the year 20000 and beyond calls for performance based specifications, warranty applications. work on recycled products and new materials.

Quality Management- the philosophy of a Quality Management Program is to exhibit cooperative relationships throughout all phases of the work. The QC/QA process provides a way to measure how you are doing. You need to develop partnerships which in the long run will make changes which will in turn produce a better product. They are happy with their program and are working on an independent assurance program which in the future will comply with CFR Chapter 23: Highway Quality Verification. Quality control by the contractor makes for smart contractors to get qualified personnel, trained and certified technicians, and make investments in laboratories and new equipment. Recipients are all doing the same tests in three states. They are all using the same process control ,production sampling and testing to know what they are producing., materials documentation and control charts provide insurance that they were tested properly with a project job mix formula. and that the field change guidelines were followed as to when change is appropriate. The QA department does production testing one split-samples at a reduced frequency of QC testing. Maybe the QA testing should go to the contractor. The personnel are required to have certification of state technicians. Their lab and equipment must be up to snuff also. The foundation of the QC/QA concept is to develop partnerships so that the exchange of information and ideas becomes commonplace.The cooperative effort in Wisconsin has been the formula of success. The present pieces of the QMP in Wisconsin are Quality Control (Acceptance);Quality Assurance; and Independent Quality Assurance Program which will lead to future compliance with CFR Chapter 23. IAP Independent Assurance Process has no friends. They have the power to check everybody. They do product testing on split samples, check WIDOT QA on a project or program basis. They also look at equipment bias. This serves as an oversight of the methods and procedures needed for the process. The IAP for technician 1,2 and 3 certification only have to run test and know what the equipment is, no philosophy. 2. Must know how to run the test, validate after the materials verification of the process. This is tough. This takes QA into purgatory. It is the contractors responsibility. Quality verification (acceptance) is going to be the Department’s responsibility We are weaning ourselves away from the DOT doing all the work and moving closer to a warranty type job. We are just opening the door, Contractors are not yet comfortable with having the QA responsibility.

The quality control will be the responsibility of the contractor. It will include the mix design (Job Mix Formula), taking care of the the personnel requirements (Certification) Laboratory and Equipment. The process control will include production sampling and testing, plant inspection, materials documentation , control charts, and job mix formula field changes in compliance with the guidelines.

The quality assurance will be the responsibility of the department. The department will do production testing on split samples at a reduced frequency to the QC testing by the contractor, they will also look for equipment bias, and will evaluate methods and procedures.

The department will be responsible for Independent verification through random sample testing, validation of materials, and verification of the process.

The mix properties measured are : air voids, VMA, gradation, % asphalt, and in-place density. Some other properties are under consideration. They are: segregation, minimum asphalt content, film thickness, aggregate bulk specific gravity(Gsb) and aggregate angularity, dust to asphalt ratio, compaction equipment and effort, and moisture damage.

The ideal would be to take the sample behind the paver, check with the QC and the work should be OK. If we get a job that has three miles of pavement out of spec, we would have a big claim and would have to develop a new system. We believe the five year warranty system works. Wisconsin’s program works good for us.

NCHRP 9-7 (Superpave QC/QA) It addresses most of NCHRP 9-7. Our system was developed with the contractors. We make changes in the specs and then hand off to the responsibility to the contractor. We are moving into contractor testing for quality control and an independent testing agency to do the quality assurance. We have no problem farming out the work

Certification Program: Source Certification; Certified Producer; Aggregate Certification Program, sample as we do AXC. Our samples per day have not changed . We do it by 500 ton lots.

Lee Gallivan talked about synthesizing NCHRP 9-7 into modules. Volume 1 and 2 are very big. Lee is working with the Lead States based on 14 projects. The distribution of the NCHRP 9-7 has not been made . Only a select few people have been privileged with a copy, NCHRP 9-7 covers a definition of functions and responsibilities; a QC system; a Binder Certification (PG Asphalt); Superpave Mix Design and production; Sampling and testing; QC activities; Non-conforming materials; Department inspection activities and a Quality acceptance plan and criteria. This is not a brand new process. We are going to put it into blocks in a usable form. It will cover the role of the contractor and the highway agency; the QC Control System -the controls and why they are needed; How to read control charts and fill out the forms needed; how to respond to whatever the measurements and tests reveal; how to take corrective action; how to select random samples; how to make them uniform.

The Binder certification is based on AASHTO PP26-96. The Superpave Mix Design and Production provides the laboratory trial mix formulas and plant verification of Plant produced HMA. Field verification and compaction rolling patterns (control strip) would be a part in this plan. Quality control activities would include the plant produced mix and the in-place compaction control. Three would be procedures for taking care of non-conforming materials. Their would also be a section on the agencies inspection activities along with a quality "acceptance" plan and criteria. This covers the Superpave Mix Specification (Design), HMA Plant production and pavement compaction. The lead states will save you all time and effort by developing for you. The due date is 4 JUL98. Chapter 2 was copied from the WIDOT spec.

NCHRP 9-7 is a good place to start. Balance is the key to the cost of the product vs.performance, cost of claims, personnel costs. A plan keeps people from taking short cuts. We are taking a very balanced approach by getting everyone involved.

Why can’t I present you with a certification process like we have in steel production? We can be headed in that direction. We need some direction, involvement and consensus within our group .

Tom Bryan stated " You have to know what you want, pay schedules, analyze performance that will result from QC/QA, If it does not meet criteria, what will it cost, what is the cost of replacement, How can we work together to make pay adjustments, Sampling and testing , Why can’t we have it like widgets coming of the assembly line. You must ask yourself," What are you looking at for measurement of pavement life, how to verify production control ;uniform sampling and testing procedures, uniform sampling and testing in the right way."

GOAL IV. Training and Certification: Laird Wieshahn, NE Roads

Mr. Wieshahn’s intent was to provide the NCAUPG members an example of a Technician Training and Certification Program which would include everything that a " totally researched " program should be made up of. Myself and others in attendance feel that the document I presented was an " over kill " for our region to accept, considering the limited resources everyone is harnessed with.

My charge for the Management Committee is to take the presented document ( this will be included in the Appendix for the Management Committee ) and reduce it to something that is effective, but minimizes the " structure " of the program. This program must include:

Laird asked, and has asked again, that any and all suggestions to this program would be appreciated. Laird will be working on " reducing " the size of the document he presented in Kansas City over the next few months. It is important that I hear for all states and provinces in an effort to address all their concerns.

Please contact Laird at :

Laird Wieshahn
Flexible Pavement Engineer
Nebraska Department of Roads
Materials and Tests Division
1500 Nebraska Highway 2
PO Box 94759
Lincoln, NE 68509-4759
Tel 402-479-4675
Fax 402-479-3975

National User/Producer Group Annual Meeting

Dave Holt announced that there will be an upcoming annual meeting of the co-chairs for the five upg’s similar to the one held at Woods Hole,MA last May. This year’s meeting will be held in the Mpls, - St Paul Paul area in June in conjunction with the Superpave Technical Working Groups. The National Asphalt User/ Producer Group is and oversight group to look at and identify issues that need to be resolved in the asphalt area. Certification is a big thing, There are a lot a of trained people out there. We went to them to find out what they and others are doing. Training is a must in the process.

GOAL IV. Plan for Development and Implementation of Uniform Quality Specifications: Gerry Huber, Heritage Research

Uniform quality specifications is broken into two parts; Existing test methods and QC/QA:

EXISTING TEST METHODS

This includes limiting the options for a test method, for example the Rice voids test, to tighten up the variability of test results as well as better repeatability. The Rice voids tests has some 27 combinations on how to accomplish the test, We don’t know how the different test procedures affect the results of the test, It also does not have a ruggedness test. What has gone through AASHTO and what hasn’t? We want to know the states that are going to SP on the web page at the SP Center. We are going to get recommendations out of the task force so that anyone can download and look at them.

QUALITY CONTROL and QUALITY ASSURANCE

Quality control and quality assurance has two basic aspects, the technical part and the administrative part. The administrative part, that is the paperwork is slightly different for every state. We cannot have uniform specifications there.

The technical part of the QC/QA is the properties to be monitored for QC and the properties to be used for QA. How we test, what we test for and how often we test all areas where uniform specifications could be developed. A draft of the QC/QA plan for SP mixture is laid out in NCHRP 9-7.There are 13 pages and you can download it at the Website at the SP Center : http://bridge.ecn.purdue.edu/~spave/ Interaction on the QC/QA plan compared to what other states are doing is important.

GOAL V. Monitor Constructability: Lloyd Bandy, APAI

As I look around , there are very few contractors in the room. We need to encourage contractors to attend these meetings. It appears that there is not any one good time to have a meeting. Right now with the winter closing in they are out there buttoning up jobs. We have talked about a hotline to find out problems on projects. In October, Lee Gallivan attended a meeting in Washington, DC with NAPA and FHWA to deal with this issue on performance of SUPERPAVE projects. I will ask Lee to report on this meeting. Lee Gallivan is one of twenty individuals from several states( AZ, MD, FL, CO), manufacturers, and others that will identify issues specific to HMA, not just SP. The group brainstormed 84 issues. They identified construction issues. They addressed who needs to do what, when and why.

Some of the Categories are:

Issues that Dale Decker brought up:

What is being proposed by this group. Next Tuesday in Phoenix they will have a written draft of the minutes of the meeting in Washington, DC. with recommendations to go to the ETG, NAPA, FHWA and will be published in January of 1998. We can have this in front of you , not a 300 page report but a 8-10 page documented highlights to go for more information. A quick and dirty booklet.

Gerry Reinke,  Mathy, reported on three SP projects they constructed IA, WI and MN. IA and MN were going at the same time. US 69 in Wright County , Iowa had the coarse aggregate below the max .density line. We used PG 58-28 and a 58-34 with some modifiers. The binder course was 19mm and the surface was 12.5mm. It was an Iowa DOT mix design. We had some problems on the other projects getting density. N initial was 86% and had no problem getting density on the IA project. Part of the reason is that the N design was 96 which was lower than the other two projects. We had N design of 109 gyrations on the other projects. If we would have had it this high on the IA project, I think we would have had trouble also. We had no trouble with segregation on any of the jobs with all coarse aggregate structures. The MN project had lots of rain. The IA project 70-80 miles south made us move on and off the MN project.. We had a smooth flow on the projects.

Future Plans: Dave Holt, MNAPA

We have some housekeeping items to cover that were left over from or Management Committee meeting yesterday morning.

We decided to go to one meeting per year in the fall.

These minutes and other information on the Center’s activities etc. will be available on the North Central Superpave Center website at : http://bridge.ecn.purdue.edu/~spave/

List of Attachments:

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NCAUPG Meeting Minutes • Fall 1997
 E-mail your comments to: ncsc@ecn.purdue.edu