Details of Minutes

Oct 05, 2000: MC² Meeting - Indianapolis, IN

Opening Remarks - Gary Whited, Chairman MC²

Jim Parry of the Wisconsin DOT has taken the place of Jim Clowers (retired) as the State representative from the Advisory Council

State Reports - Measuring Smoothness Jim Parry, WI DOT , Moderator

Handouts were provided of the individual State reports.

IL, Brian Pfeifer Breakpoint for smoothness requirement is 45 MPH. Just held a rodeo for profilometers. Looking at 0 blanking band use.

IA, Jim Groves Still looking at use of 0 blanking band, no commitment yet. Use a breakpoint for smoothness specification at 45 MPH. Historically used the 1/4 point on the lane for measurement, but now looking at wheel track measurement.

KS, John Wojakowski Use a California profilograph. Began use of 0 blanking band in 1995. Non-contact profilograph use is allowed, but must operate in same format as California profilograph (automated or manual operation).

One contractor returns 25% of bonus received to paving crew.

MI, John Staton Use a Ride Quality Index that includes the perception of the user. Use a California profilograph to locate bumps in pavement. A 5 mm blanking band is used. Use of metric system will be discontinued next week. Looking at the use of 0 blanking band.

MN, Doug Schwartz Use a California profilograph, but don=t have a high confidence level with the device. Will continue to use it until something better comes along. Use a 0.2' blanking band. Payment based on inches per mile ranges as follows; 4-6" 100% pay, 6-8" - 0 to 1.00 deduction, 0-4" 0 to 0.12 incentive, >8" must be ground to 6"/mi. Will look at use of 0 blanking band and use of lightweight profilometer. Also looking at grinding all bridge decks in the St.Paul/Minneapolis area for smoothness.

Use of the incentives paid in MN have generally gone to improvement in pavement equipment by the contractors.

OH, Keith Keeran Use the California profilograph computerized version. OH has a test track for calibration of the profilographs used by the contractors. The equipment must be cleared on the track for use every three years. Provide a 4% incentive for smoothness 2-4 "/mi and a 2% incentive for 4-5 "/mi.

WI, Jim Parry Use computerized California profilograph for projects under the 1997 QM specification. Looking at non-contact profilometer use.

MO, Tom Keith Looking at use of AWhite Velvet@ grinding for all pavements to obtain smoothness desired. Use one bonus for smoothness of paving operation and another bonus for improved smoothness through grinding. Able to immediately cure pavement, and grinder can do something the paver cannot. Get benefits of both smoother ride and friction improvement. In those areas where this was part of the contract, the public has provided very positive response to the ride quality.

IN, A profilograph is used for speeds >70 KPH. The profilograph is not generally used for lower speeds, but there is a specification for smoothness. Smoothness requirements apply up to within 15 of bridges on mainline through lanes. Ramps are not included. A 4.9 m straightedge is used where the profilograph is not specified. A study was done through Purdue on evaluation of not-contact lightweight profilers. More information and demonstrated improvement in the devices is needed before IN will use a lightweight profiler.

There is no bonus provision for non-QA projects. Payment varies from 100% for 0-30 mm/160 m to correction requirements for >38 mm/160 m. QA projects have a bonus provision, up to 3% bonus for 0-13 mm/160 m and corrective work required for >25 mm/160 m (100% pay for 7 /mi target mean and 103% pay for 5 /mi target mean). Looking at the use of 0 blanking band in the specifications next year.

A new tining specification is in use (reflects the WI pavement noise research report findings).

Ted Ferragut - TDC Partners Performance Related Specifications (PRS)

A national workshop was held in Orlando Florida in May of this year for performance related specifications. Sponsors were FHWA, FL DOT, and NQI.

What happened at the workshop? Need national and regional coordination No plan yet. Why no plan? Minimal communal understanding of the subject More complexity than thought going in to the subject A report on PRS will be available on the web site soon

Performance choices can be achieved via two approaches: specifications or warranty. Early work on performance related specifications began in 1965. A persistent question in our contracts where performance relations are considered is Are we measuring the right things?

Industry is generally supportive of the concept of PRS, however, there is concern for the variability of measurement and structuring of increased incentives to create a comfortable contract environment. PRS is considered as an alternate to warranty contracting.

In the arena of Quality Characteristics vs. Distress Measurement Requirements, the following considerations are critical.

1. Hold the construction contractor accountable ONLY for those things under the contractors control. 2. Establish a credible performance prediction model 3. Life Cycle Cost Analysis as-designed to as-built 4. Acceptance plans with defined risks and statistically based criteria that provide quality measurement results within a short time frame (24-48 hrs. for PCCP) 5. Clarity and simplicity in specifications and contract administration procedures

Suggestions where PRS is to be used: 1. If PRS is used, drop method specification requirements 2. Promote Non-destructive Testing in-situ 3. Include process control 4. Prediction techniques should be based on mechanistic models 5. Include user cost in LCCA

Benefits received in PRS use: 1. Pay factors that mean something 2. Focus on testing 3. Performance and quality is optimized through a best value approach 4. PRS serves as a bridge from design to construction 5. Product life determination can be better estimated

Challenges to PRS use: 1. Development of credible performance prediction models 2. Higher risk perception must be overcome 3. Method specifications arent tied directly to performance but are historically comfortable 4. Industry is too busy and resource reduced to provide needed support/input.

PRS vs Warranty PRS uses that same project time as a method specified project, models performance in anticipated results, and there is no increase in the amount of inspection required to complete construction. Warranties add 3 to 5 years to the overall construction contract time, measure actual performance, and require inspection over a longer time period than method specified projects.

MC² was requested to take on PRS as an endeavor/goal to improve and to put warranty use to the test against PRS.

Discussion Comments: There is a conflict between the complexity of PRS and the need to clarify and simplify specifications and administrative procedures. Industry acceptance of statistics, and the lack thereof, pushes opinion more toward use of warranties than PRS. Prediction of LCCA with variants is suffering from lack of information. Traffic prediction validity does not lend itself to PRS use. The sensitivity of multiple variables, from materials and their use through the environment of construction and service life maintenance or preservation has yet to be addressed sufficiently to place a high level of confidence in the use of PRS, except on a reduced focus of involvement (one slice of performance of a product through its functional or structural life span). Perhaps there is room for a middle ground or relative performance approach to operate within those variables which can be controlled. There is a need for change in inspection techniques, tests/test methods, and timely decision-making.

PRS from INDOT Perspective Tim Bertram, Chief of Contracts and Construction Division

In 1970 method specifications were used. In 1976 End-Result Specifications were tried unsuccessfully, but since 1985 when Quality Assurance specifications were used further steps have brought IN DOT to the point where we will address the ultimate goal of Performance Contracting.

How do you contract for performance? One way is to measure the performance of the product as it performs. This is really a warranty. The other way is to predict how the product will perform by measuring characteristics which effect performance, which is to measure the quality characteristics that are under the control of the contractor.

Under method specifications the definition of success was that the specifications were met and the contractor made money. The specifications were met as a rule but, did that have any bearing on performance of the product? Not necessarily.

In performance specifications success equals a balance of performance risk with innovation being rewarded.

INDOT advertised its 1st performance related specification for concrete pavement December 27, 1999, held a well attended pre-bid conference January 20, and let the project February 22, 2000. The application is Level I PRS project specification developed by joint effort of Purdue University, ERES Consultants, FHWA, INDOT and industry representatives. Their effort began as a group in the summer of 1999. The project is located on I-465 from I-74 to north of U.S. 52 on the southeast side of Indianapolis and involves complete pavement and bridge replacement on I-465 including two interchanges. The full contract was successfully bid at $31 million+ with the concrete pavement items accounting for about $5 million. Approximately 66% of the concrete pavement will be constructed under the performance related specifications. Milestone Contractors, L.P. was the successful bidder and the concrete paving subcontractor is Berns Construction Company.

A pre-paving meeting was held May 12, 2000 to discuss concrete paving scheduling and coordination of the use of FHWAs mobile concrete laboratory. The mobile laboratory was used during the first phase pf the PRS concrete paving for informational and experimental testing.

Level I PRS is really only improved QC/QA specifications based on quantified relationships between performance and construction quality characteristics which are under the contractors control; that is, concrete strength, thickness, and smoothness for our project. These characteristics are measured under our current QC/QA specifications. However, under the Level I PRS contract, the quality level obtained by the contractor for these characteristics is used for the prediction of pavement performance and establishment of the payment made to the contractor. Payment is based on a performance formula using a weighted average of the quality characteristics (strength, thickness, and smoothness).

There is very little difference in the administration of the performance related specification and our regular QC./QA concrete specifications. The sublot and lot sizes are the same as they are for our QC/QA concrete pavement. Lots are 6000 m2 or 7200 sq.yds. and sublots are 2000 m2 or 2400 sq. yds. There is some additional work in correlating the smoothness with the sublots. We are going to investigate this approach to see if it really makes that much difference in the overall pay factor.

Data from this contract will be used to expand the next PRS contract specification coverage (Level II PRS). Level II PRS is a transitional step within the performance measurement scheme of things to increase the inclusion of those measured characteristics related to the performance of the pavement. Pay factors, tweaking of the pay factor measurement system, and testing method changes would be part of the transitional efforts.

What is leading us in this direction? Continued increase in Interstate traffic and weight loading has occurred since 1970 and doesnt show any signs of letting up. Traffic has more than doubled and loadings are 5 times as much. The NQI survey of our customers, the traveling public showed us that our customers want a safe and smooth road but they dont like construction delays. They want us in and out of the way quickly and they want us to then stay out of their way and dont come back. What we did in 1970 wont work today. In 1970 INDOT had 8000 employees; today we have less than 4800. In 1970 we watched and tested everything we thought the contractor did. We cant do that today and in reality dont have to.

In performance contracting, responsibility for the product is shifting more toward industry. However, the PRS must be fair and equitable. PRS are part of a process of continuous quality improvement in highway construction. A better understanding of materials and construction quality characteristics has made this development possible. The use and refinement of PRS will further increase this understanding. The bottom line is more cost effective construction and better, longer-lasting roads.

Cole Graveen, Purdue University Data Evaluation and Modeling

The simulation software is based on physical models to be used to predict distress and user costs over time.

Three levels of PRS are to be used in a gradual approach to consideration of PRS as a normal option for contract use in concrete pavements. Level I - Use 3 to 5 quality characteristics measurements (this contract underway) - Use current QA testing for acceptance - Use simulated Pay Factor Charts

Level II - Transition stage - Use 5 quality characteristics for acceptance - Use QA testing with in situ and NDT testing methods - Simulated Life Cycle Costing and use of one Pay Factor Chart

Level III Final, or Ideal PRS - Possible increase in number of quality characteristics measured - All testing is done rapidly and is NDT

The existing pavement specification was reviewed and input tables were set up (121+ inputs). Iterative software trials were run and revisions made to the specifications. Coordination with industry was close.

Difficulties that had to be addressed: Time constraint Some of the hard data inputs (mainly rehabilitation procedures) Conservative design practices (over design) and continuous mainline/shoulder paving Smoothness combinations from sublots User costs Software glitches as the iterations took place

Maximum and minimum quality levels were set. A composite Pay Factor was used which consisted of the average of the pay factors for strength, smoothness, and thickness.

During the side-by-side testing, the following methods were tried: Maturity test meter use for strength development Impact-Echo Test for in situ thickness measurement Measure P-Wave velocity as a check against strength Anticipated results from the I-465 project: Increased knowledge Means and standard deviations relation to payment Increased use of NDT methods Early acceptance and payment Information needed for statistical analysis Contractor feedback Level I and II simulation comparisons Compare charts with computer program that determines the Pay Factor

Rick Smutzer, Materials Engineer INDOT Testing and Lessons Learned

Conventional QC testing was performed to determine: Plastic concrete properties (slump, air, unit weight) Strength (flexural and compressive) Split tensile strength testing

Non-Destructive Testing performed was: Maturity Meter Impact Echo Test

Testing for Durability included: Rapid Chloride Permeability Water/Cementitious material ratio Air void analyzer (Danish Air Meter) HiperPave program use

Comparative testing of concrete was done from the truck and from in front of the paver.

Lessons learned: Need to adjust the incentive/disencentive to actual thickness to be used and achieved in the field No appreciable difference in pavement smoothness measurements were noted between the hours of 8AM to 1PM. Interested in Wisconsin data and experience using a probe test for thickness measurement payment.

Paul Tennis, PCA Task Force Report Opening Pavement to Traffic guideline/recommendations

The draft text of the model specification was discussed by the task force. There is general support for the format, options for equipment, AASHTO and ASTM test methods, metric and English units, and flexural or compressive strength use.

There is disagreement on the proposed strength levels. Will look at existing research and make a recommendation for a rational approach to strength requirements and add language covering patching work.

Tom Keith, MO DOT Task Force Report Uniform Dowell Basket Design and Fabrication

The task force met Oct. 5.

Responses have been received from 7 states. The length and 3 sizes indicated as used are generally the same. 5 states use one bar size. Most states do not require basket configuration. This comes from the manufacturers. The states would be willing to use a generic (1 or 2 size) basket.

We need to look more at the coatings differences. Also there are lubrication differences but not anything where a hard stance is taken.

All states use the same spacing (12) except MI and when MI changes from metric back to the English measurement system, they will all then probably be the same.

There is enough commonality to proceed with a recommendation at this time. There will be further coordination with industry to define their stance on the question. Once the industry survey and coordination is completed, (wire size, commonality, etc.), a draft document will be sent out. There are no patents involved for baskets.

Completion of the draft document and comment period is anticipated by the Spring 2001 meeting.

Dale Harrington, Director Center for Portland Cement Concrete Pavement Technology

In 1999 the center was proposed. In April 2000 the Center was established. Funding/resources were provided by Iowa CPA, Iowa DOT, Iowa State Univ., for three years of operation.

Jim Cable is the Chair of the Research Committee. There is also a standing committee for technology transfer. An advisory board of 20 people has been set up and a research engineer has been hired who will perform both teaching and research.

In technology transfer there is a need: - to improve education of undergraduates in concrete - to recruit personnel who will be active in the future concrete fields - to address community college technician program needs - expand QC/QA capabilities

Research will be done using the ISU lab, IA DOT matls lab, and field labs around the state.

A tie between the MC² and the Center is desired to provide a forum crossover. The Center is ready for any reasonable partnering and goal sharing with the MC².

In 1998 in Des Moines an urban specification for concrete work was established by 16 local units of government. Work will continue to take the specification to a statewide use in coordination between The Center and IDOT.

General Discussion/Panel

The general membership present at the meeting was asked to identify areas of concern and issues that needed to be addressed in the concrete arena. Voting was done to establish the top issues for discussion and possible further pursuit. Each person was given three votes to cast for the issues of importance to them or their organization.

The top vote getters were: 1. Durability prediction methods and construction to improve durability 2. Non-destructive testing what do you want? 3. MC² cement acceptance process why arent more states using this? 4. Fly ash use and restrictions in state specifications/procedures.

Each State representative then described their respective state positions or methods used to address these issues and fielded questions from the general audience.

DURABILITY OF CONCRETE

KS Looking at lowering the required cement content and testing for permeability. Testing for permeability is done at 56 days using the rapid chloride permeability test. Use less cement and achieve less permeability for the same w/c ratio. An effect of air content has been seen; that is, as air content increases so does the permeability. Looking at the impact of higher air content and F/T durability now.

W/C is high on the list of concerns at the time of construction. Working on development of a test method. Would very much like to have a way to quickly evaluate the air system in hardened concrete (same desire of MO) dealing with the spacing factor. The unit weight check is a good tool to use for total air content variation.

Comment WRGrace: The sand in the mix will determine the stability of the air system (#30 to #50). There is a correlation between the mix cycle (Time and effort required to build the air system is directly related to the integrity of the system built. Air systems quickly and easily built due to mix characteristics, mixing and admixture reactions will not last as long as systems that require more effort and time to become extant.) and the air system development. Also, the use of superplasticizers and water reducers may impact the air system. A list of papers concerning the subject were referred to by MasterBuilders. Information on the reference papers will be forwarded to Jim Cable for posting on the MC² web page.

WI Looking at testing of shrinkage and impact due to reinforcement.

NDT WHAT DO YOU WANT?

Maturity meter use.

MN Have used the maturity meters but industry feels that they dont need to use it. A paper will be presented at TRB showing lack of use due to a set protocol not being available. Recalibration of the maturity meter when there is a JMF change is a chore.

NE January 01 specification will include the maturity meter. OH No use of maturity meter to date MO Used the maturity meter on a couple projects (1 was fast track) and believe it to be a good idea. MI Have done some work with the meter but industry is not interested or comfortable with it. Due to the speed of progress on the jobs, by the time the contractor is comfortable with the meter, the job is over. Looked at the IA IMs/specs and designed around them. Maturity meters were lent to contractors for their use. IL Looked at the use of maturity meters but a problem was noted when the air content of the mix was not the same as initial calibration. - Looked at use of the W/C meter - Looked at use of Impact-Echo but there were bugs in the equipment when used years ago. IA -

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