Details of Minutes

Oct 18, 2001: MC² Meeting - Ames, IA

Jim Cable, following a moment of silence for the current world activities and in support or our Chairman Gerry Robach, called the meeting to order.

The following comments represent the key points made by the speakers or the audience relative to the agenda items for the meeting. I. Improved Portable Mixing-Bill Cape (James Cape & Co.) Innovation is expensive and difficult to bring about. Even though it is encouraged is very difficult to achieve. Bill described a new highly portable mixer that is self-erecting, moves quickly and can produce continuous high quality mix. One has been designed for him and he reported on the success of the machine. He asked for a machine that must pass mixer uniformity and air tests. The goals of the mixer were mobility, high production, better mixing & uniformity, high accuracy, user-friendly controls, environmentally friendly. He also requested a mixer that could handle several different types of mixes. Previous difficulty hitting w/c ratios (problem) led to this innovation. The system is operational and has produced continuous quality concrete in 2001. They are still working on the dust control system, but goal is to be able to put this in a downtown environment without people being exposed to the dust. The system is HYPER-MOBILE: No crane required for erection. Silo is self-erecting and no concrete foundations required under most conditions. There is no need for loading bins and charging conveyorsmeans fewer loads to set-up transport. The control trailer, admix trailer and generator set trailer are combined into one trailer. Entire plant can be set up and certified in less than an 8 hr. day The plant is not a drum mixer, but has a vertical cement silo that is at the top of the mixer and therefore, water is added uniformly as all the materials enter the mixer and not at a single point. The silo is self-erecting and has the ability to add three more internal bins. The mixer is a single box with 13 CY capacity (vibrated & compacted) with a twin shaft mixer violently agitates ingredients insuring uniformity in less than 30 seconds. It can produce about 50 batches of 12 CY per hour. It is fed by dual cement batchers to ensure rapid and accurate weighing of cement and fly ash. Overhead cement silo gravity feeds into weigh hopper and the total cementious material pneumatically fed into the mixer. Is compliant with all safety standards (OSHA/MSHA). The weigh belts have a very precise control of the aggregate feed. HIGH UNIFORMITY - Recent uniformity tests at the plant were able to uniformly mix 1.5 slump concrete in 30 seconds. High early strengths and very low standard deviation on compressive strengths w/excellent uniformity and cement dispersion were identified. Low slump concrete and mixes using fly ash can be mixed rapidly and uniformly. Twin shaft mixers uniformly mix concrete, cement treated base and soil cement. The 250-horse motor to spin the twin shafts. 6 times more mixing energy in 30 seconds with this, than in a drum mixer in 1 minute. Materials mix very quickly, although partially due to the mixer, is also due to the weigh belts that uniformly add aggregate. The ultimate goal is to mix 12 cubic yards concrete in 12 seconds. The system is very quiet and one does not know it is running until you see the concrete coming out of it. It has an integral dust collection system with an enclosed mixing chamber minimizes cement dust. By Products - This mixer is the only one available-prototype. a. It can be used in low or high production areas. b. Wet and dry pockets did not exist in the barrier walls-uniformity was excellent. c. The Profilograph readings for pavements are being lowered 25-30%. d. The Minnesota specs allow for new technology and they would be happy to have this plant brought there. e. Hyper-clean aggregates. The ability to control air goes out the window when more fines are introduced. f.Mixture uniformity and air tests were the only requirements placed by the Wisconsin DOT for them to be able to prototype this plant. Questions a. How do take gradation samples off the belt? Could leave the bulkhead off on one side to reach right in and take it off the belt. Many states allow the gradation taken from the stockpile. b. How is the moisture in the aggregate considered? Moisture measuring-dont have a real good way of measuring and then adding water. We use moisture meters only as a guide. Much better off watching the slump meters. c. Computers run everything (3 of them) and fear is that they may have problems at some point. d. The required plant site is -250 ft long and 50 ft wide on one job. Think the plant could be fit and operated into 2/3 of an acre. e. Working toward a zero emissions plant.

Evaluation of Mixing Time vs. Concrete Quality-Jim Cable

This Iowa project asked the researcher to do 2 things-look at mix times vs. consistency of the mix and explore options of contractor designed mixes. The mix times chosen were 30, 45, and 60 seconds. The research found that with the drum mixer got good consistency at 60 second mix times, but less consistency at the 45 and 30 second mix times. The results of this work led to many contractor mix designs in Iowa and a move away from cookbook designs. Additional interest is being shown in mixers such as used in the preparation of drilling mud and those described in the previous presentation. Innovations in concrete movement on the project-Bruce Chapin, Baker Concrete Rep. (Monroe, Ohio) The contractor wanted to set up the batch plant along the side of the turnpike and conveyor across the turnpike to the median. They didnt know how to conveyor concrete without environmental problems, but thought it was a good idea so they developed initial plans with their concerns and requirements (66,000 cy of concrete). A conveyor system was developed with a 130 ft. long conveyor that would be self-supporting and would be elevated above the turnpike. It needed a containment trough in order to keep anything from falling onto the traffic below. The contractor was forced to raise the plant an extra 14 ft. in order to get conveyor high enough to be within standards of structures above the roadway.

They found no loss of air with this method of transporting the concrete and had no concrete rejected on either job. They have not used it to convey base type materials yet. All stone and sand was brought in by truck through the turnpike gates.

Reducing the time for pavement reconstruction-Mark Bare, Cedar Valley Construction

Mark described the key elements of the project which was the reconstruction of I-80 around the west and north sides of Des Moines, Iowa. Five core contractors: Grader, pave, and bridge contractors were coordinated under one prime contractor and one DOT office. There was a lot of interaction with the DOT and the main contractor, which helped to improve the speed of finishing the project.

Questions- a. Drop dead completion dates- The contract set up with such dates, and if any work impacted the completion date it would go into the change order. They were essential to keeping the work on time. b. How much time between letting date and construction? Two months, was enough time because the contractor had done some of the legwork before hand. Orig. contract was for $38 million and change orders amounted to $ 4 million. c. Does the incentive work flow down to the workers? Yes to the salaried guys, but not to the hourly. d. A lot of bridge removal and reconstruction work was done at night. Spent very little time getting rid of the old stuff.

Fast tracking Lane Replacements-Jeff Roesler, Univ. of Illinois

Jeff described the work done on Interstate 10-IPRF funded research monitoring of the project only. Traffic constraints are always a problem in California. Mostly, the project was successful due to good planning. Cal Trans has identified about 3,000 lane miles needing replaced/rehabilitated in California. BACKGROUND- The project is located 30 miles east of Los Angeles near Pomona, CA. There was a lot of other free way options for residents to use. Two of 4 eastbound lanes closed for the weekend project. Reconstructed only lane #3 but needed to remove only concrete slab of 625 panels. FSHCC (Fast setting hydraulic cement concrete) (more expensive material) used to replace old PCC in an effort to speed up the process. Dowel and tie bars used here, where traditionally California never used them before. Once started, the work was a continuous operation from removal to replacement.

Flexural strengths of 400 psi in 4 hours, 600 psi at 28 days, max contraction in air (.053%). Minimum thermal stability (90%) was obtained from cement tubes in hot water baths to avoid calcium aluminum cements being present. The cube strength of 2500 psi at 3 hours and 5000 psi at 3 days was obtained. This cement does not fall under ASTM 150 specs. The contractor could have used conventional mixes after all because the road was not opened until 55 hours later. CONSTRAINTS: The owner imposed a 2.8 lane-km in55 hour weekend closure from 22:00 Friday to 5:00 Monday with a $500,000 bonus for successful completion and a $10,000 per 10 minutes for lanes not opened. The concrete batch plant was 5 miles from site and the concrete was hauled with ready mix trucks and placed with a vibrating screed. It was a first for the use of mobile concrete barriers in California. DEMOLITION PLAN The contractor first Pre-cut the slabs, then removed them with the lift out, non-impact method. He used three crews with large hoes and trucks. PAVING PLAN - The contractor used a rotating screed (clary), a batch plant with a capacity of 120 cy/hr to dry mix the concrete and deposit it in ready mix trucks of 8 cy capacity. Concrete mixer trucks mobilized included 27 due to the length of haul and traffic. The mix needed to be continuously agitated or the mix starts to set up. Joint sawing was done 2-3 hours after paving. The contractor did find a problem washing mixers out and took 10-15 minutes per truck with high-powered washers to achieve the clean vehicle. The project was successful and completion came about 1:00 a.m. on Monday morning. During the construction, traffic volume was cut in half due to traffic planning and public notice. The largest delay was about 19 minutes on Saturday afternoon. Some 466 trucks were loaded by demolition contractor (1.32 panels/truck). The truck efficiencies worked out to 47% per truck with an average demolition rate of 10 panels/hr./team and an 82% demolition efficiency of the project CONCRETE DELIVERY - Some 440 truck loads of concrete at an average of 1.4/panels/truck and a transit mixer truck efficiency of 87%, accounted for an average rate of paving of 14+ panels/hr (15 ft. panels). The average discharge rate 6 minutes/truck attained for an efficiency rate of concrete operations of efficiency of concrete operation 67% and an average turnaround time of 74 minutes. WHAT IF SCENARIOS: What if the 100% concrete delivery efficiency: then 40 hrs. vs. 47 hrs of paving would have been required. If 10 cy concrete mixer trucks were used then 35 hrs. vs. 47 hrs would have been required. If the whole 3 demolition crews were used, then 22 hrs. vs. 30 hrs. of demolition could have been attained. HOW TO INCREASE WEEKEND PRODUCTION: Faster concrete delivery could have been attained with a central drum mixer, end dump trucks or 10 cy mixer trucks, higher concrete delivery efficiency. This type of work requires two 12 access lanes on site, may not have provided room for a conventional paver, and impact demolition could have increased production. CONSTRUCTION WINDOW FACTS- The weekend closure allowed for 54% more slabs done than in nighttime closures CASE STUDY SUMMARY FSHCC can be placed efficiently. Mixer trucks and plant are constraints. Urban rehab is slowed by access and traffic management is paramount with management of site traffic being essential. Questions that remain: How low strength can be used to open to traffic depends on the thickness of the slab. ACI just published a report on this issue of strength. Performance and methods specs combination was difficult to deal with, use one or the other but do not mix.

Accelerated Construction-Where are we going?-Ted Ferragut, TDC partners

There is a push to accelerate ALL types of projects. Therefore, are also trying to accelerate innovation. TRB Task Force A5T60-comes from special report 249-Building momentum for change. The report envisions: Neutral board, Public-private sharing, and Constructive activities.

Identify barriers- First barrier-innovation that requires multi-disciplined, multi-tiered efforts will be hindered until at least one of the impacted bodies assumes a strong leadership role that is fully recognized and sanctioned by the other impacted bodies.

Three major conclusions; Emerging critical national problem, Many different strategies and techniques, and No singular solution will work. One of these major repairs (such as California job) takes so much in resources that a DOT can only handle one of the projects at a time. How will they be able to manage several high profile/rapid projects at one time. TEN POINT STRATEGIC PLAN; 1. National information, 2. Corridor improvements, 3.Work zone traffic mgt., 4. Contracting, 5. Stay out techniques, 6. Utilities, 7. Modular/prefab construction, 8. Worker safety/health, 9. Training and education, 10. Communications. The group wants to establish a national clearinghouse to collect all the available information about high-speed paving projects. Corridor construction-new concept rather than simply as a project. Work Zone Traffic Management includes training construction personnel(not happening), is it maintain speed or reduce speed, pre-project customer not aware of work zones, and more customer information, updates and changes. Utility delays are common, with serious problems with few success stories, the DOT receives the blame, utilities have huge workload and staff limitations and the DOT is short on advanced planning. ACTT-Accelerated Construction Technology Team. COMMENT-Need to keep an eye on is the idea that we make a lot of guesses on what the traveling public is up to. Keep up with the traveling public rather than guessing. THREE issues with high-speed projects: 1) getting contractor paid turn over 4-5 million project in a week then need to wait for another month to get paid. 2) residual problems after the fact-they dont settle 3) Another problem is high-speed inspections-Often need to finish the job without test results available to ensure quality of what is being done.

Must get in early, before the budget is established. If not, it is very difficult to get anything changed. There is also a lack of technology transfer re: traffic management.

Pooled Fund Study-Dale Harrington, CTRE

Dale described the history of the project from concept of implementing PCC excellence in highway projects to (Fal1 1999) to the specifics of materials and processing (Spring 2001) has moved through to both materials and construction practices (Fall 2001). Dale asked for input in order to help us understand if we are heading in the right direction with this project. Want to come up with the training modules that work so they will readily transmit the information to the people who really need it.

He indicated that most PCC Pavement Distress is construction related in early age concrete pavements and materials related distress in the advanced age pavements The stages of this project are as follows: Stage I-materials related (proper mix, adequate w/c ratios, controlled cements, etc) Stage II-construction related (properly consolidated pavement, properly cured, etc) Stage III-Construction related (1-8 yrs of life) gradual loss of water tightness, cracks and micro cracks become more interconnected and infilling of air voids begins. Stage IV-(older than 8 yr. Pavements) Normal surface drying causes cement gel to shrink and crack.

THE ISSUE: Concrete mixtures are complex chemical and physical systems with a variety of ingredients and sources, different mixture proportions, mixing procedures differ and curing technologies. Construction practices are not always integrated with material practices. THE SOLUTION: A pooled fund study to characterize materials, compatibilitys, and construction procedures is key to increasing durability of the pavements. There is a need to understand materials used, obtain quick answers and procedures to get into the zone of optimization. The study can bring together material science and construction practices, and develop guidelines to simplify and specify how to produce affordable, durable, constructible, reliable pavements. Training modules are targeted at Preliminary guidelines for prevention of premature pavement distress, Compatibility identification-training modification, Material property integration, Best construction practices, and Material and construction. The study phases are identified as follows Phase I 1.1 Administrative 1.1.1 Assemble technical review committee 1.1.2 Organize specific task assignments 1.2 Literature Review 1.2.1 Identify critical issues/test methods 1.2.2 FHWA, NCHRP, IPRF, ACI, ACPA, State DOTs 1.3 Field Monitoring 1.3.1 Ascertain prevalence of compatibility problems 1.3.2 Each member asked to identify 3-5 projects 1.3.3 Determine baseline materials and properties for selected projects 1.3.4 If problem materials/properties/practices examined to see what went wrong (if it did) 1.4 Summary of Literature and field monitoring reviews 1.4.1 Identify critical material and concrete property issues

Phase II 1.1 Laboratory testing 1.1.1 Identify potential modifications for incompatible material combinations 1.1.2 Effects and relationships of mixer type, mixing speed, duration, etc. on microstructure 1.2 Field Verification Testing 1.2.1 Investigate property effects of construction procedures with various materials 1.3 Compatibility identification modification 1.3.1 Re-evaluate selected mixes using field trials 1.3.2 Training module 2

Phase III 3.1 Material Property Integration (training module 3) 3.1.1 Integrate concrete material elements into industry practices 3.2 System Integration 3.2.1 Integrate material elements into system design, pavement distress, relief & prevention and serviceability issues. 3.3 Guideline Review 3.3.1 Two years after guideline implementation Proposed Involvements include the Federal Highway Administration for initial funding and the Midwest Concrete Consortium for the administration, and final funding. Inclusion of each state would include identification of two individuals each to serve on technical committee and a letter of support for the project. The Iowa DOT has agreed to be the lead state and assume the administrative duties. Ian MacGillivray posed the question of - Would your state be interested in this type of an effort? Yes was received from Minnesota, Nebraska, Kansas with Iowa taking the lead, although would certainly be willing to work with other states if they wanted to do that. It is most likely that such a funding package would start in FY 03 due to timing. Cable will ask for state support in a letter and those will be shared with an FHWA/TRB oversight panel (Dec. 18, 2001) that is designed to catch their eye and win their approval. Industry representatives asked if there was anything that precludes industry from contributing money into this project? The FHWA would encourage industry participation. Although the money could not go into the same pool funded account, but could definitely arrange a match account for industry to participate. Gordon indicated that industry would be interested in participating in something like this. Management committees are typically set up to provide management and oversight for the research projects. NCHRP constraints include the time it takes to get the proposal approved, form a new panel that sometimes loses focus on things Dale indicated that Dec 13, is quick and would like to send out a letter from MC² to the states to ask for their support in this effort. Those present agreed and asked Cable to send such a letter. The response will require a letter of support and the names of two persons to serve from each state on the administrative committee. It doesnt need to be a formal response yet, but need an expression of intent or support. There is a lot of flexibility in the study and a lot of opportunity for people to contribute in many ways. Not always dollars, sometimes intellectual input from researchers etc. This seems to be a pooled-fund winner.

PCC Lab Presentation-Kejin Wang Kejin described the development of the research lab for PCC lab materials all in one place with the goal of focusing on the durability of concrete with the key issues. The total cost of lab is around $365,700 from sources such as ICPA, ISU, IDOT, and Holnam donated equipment. The Proposed Lab equipment includes:

Mixers standard curing room Scales for weighing environmental control room Tools for mixing, casting & finishing floor oven Standard casting modes (cylinder, cubic, beam) water bath for steam curing Autoclave curing

For fresh concrete property measurements: Standard or modified slump test apparatus Vicat apparatus for setting time tests Flow table for mortar/paste flow property Adiabatic calorimeter for heat of hydration Rheometer for concrete flow property Air meter and air voids analyzer

For mechanical testing of hardened concrete >600 kip open-loop machine 220 kip closed-loop MTS package

Durability Rapid chloride permeability apparatus Chloride content measurement tool Linear polarization measurement for steel corrosion tests Freeze-thaw apparatus Shrinkage (autogeneous, drying & thermal) testing apparatus Length comparator for shrinkage and expansion tests

STATE REPORTS: - Jim Perry-handed out copies of the state reports received in advance. The topic for this meeting was surface texturing methods and specifications.

a. Wisconsin-PCCP Texturing involves mostly transverse tine finish, with longitudinal Astroturf drag first, no overlap. Rarely uniform depth on the tining. Also started w/skewed joints and were still sealing joints. Standard 1 tine spacing until 1990s when attention turned to noise level. The DOT conducted research on test sections of transverse, longitudinal and skewed tining. Various random spacing patterns were built to reduce noise. They initiated research on the test sections that grew to regional and several states pavements sections were explored. Marquette Univ. did the study and published the report. Two quietest patterns were skewed and transverse. Some type of random pattern seemed to work better and industry voluntarily started with transverse random spacing sequence. Wisconsin has not fully adopted the use of longitudinal tining for safety reasons. They may eventually adopt that method but will require certain restrictions. The are planning some pilot projects for further research on the topic of safety. Some of the concerns are: 1 Control of vehicles-some drivers perceived less ability to control vehicles. 2. Two wheel vehicle lack of perceived control 3. Ice retention has been a concern with the transverse.

b. OHIO-copy of report attached?

c. NEBRASKA-see attached report. Last year Nebraska changed their policy on mainline pavements. Frequently there was a lack of uniformity in the tining-sometimes too deep. They went to the longitudinal tining in order to aid in getting the cure on the concrete early. They have not had a lot of complaints about noise, but the longitudinal tining is much quieter. Bridge decks are a different issue. Nebraska tried to go to burlap drag or Astroturf drag on bridges and ran into a federal disagreement. Using a finn bull float, while it although meets with federal approval, but actually made a smoother surface and decreased the skid prevention ability. Mainline paving will all be longitudinal from now on.

d. MISSOURI-Is moving toward more longitudinal tinning. It is an option at this time.

e. MICHIGAN- The DOT uses 1/2 on center , 1/8 wide, and 1/8 to 3/16 deep. These are the correct numbers for the report. The noise issue has become a big issue recently. The current model is longitudinal tining on anything 45 mph or more in design speed. They are doing 2 pilot projects with this method to check. They noted they have had ½ spacing on transverse tining for a long time and have had much less noise difficulty with that. Also, the I-275 finish with the diamond grinding and the final noise numbers will be available soon.

f. KENTUCKY-no report forthcoming from them.

g. KANSAS-The state has found that the natural process if you can get on very early can almost always get the depth requirement and that has a big impact as to whether or not you get the friction numbers and lower the noise. We are going to the random pattern to reduce the noise.

h. IOWA-Our specification has an option for transverse or longitudinal tining, but the transverse requires the blanking band , which left the contractors to make the decision, and they mostly go with the longitudinal tining. Our longitudinal tining machine is run on the string line for guidance, which has worked very well. Now require the center line blanking band-or leave out the center line so the saw line doesnt follow the tinning mark. Drainage is not an issue as the grooves are not even troughs and thats how the water gets off the road. We require macro textures on mainline high speed ramps. Iowa uses a visual aid to explain different depths to the field staff. The longitudinal spacing of the tining is ¾ inch. The longitudinal tining has demonstrated a major impact on curing at early ages and allows the contractor to tine and cure in one pass. In addition to the string line requirement have you got any equipment requirements(Track vs. rubber)? No. The contractor must watch when they stop, if the tines arent lifted can sometime get a trough. Sometimes the trough is deep enough to cause problem with later random cracking. Different types of tines can make an impact also.

i. INDIANA- The state has not looking at longitudinal tining yet. They have adopted the Marquette totally random transverse tining method. They have completed a couple of small trials on longitudinal but nothing significant.

j. ILLINOIS-Current specs require artificial turf drag for roads 40 mph. or less. A 1976-1997 friction study looked at combination of texturing methods that worked best and settled on artificial turf drag and transverse tinning. They are moving in the direction that Wisconsin is with the random spacing transverse. They have a couple small sections looking at skewed random spacing. They also hope to move into longitudinal tining at some point. They dont have a lot of noise problems but think the longitudinal tining method will help out with that.

k. MINNESOTA- History: Non-tined concrete pavement surface texture. Whining was a big issue-why we quit doing tining completely? Neighborhood group near I-394 that couldnt put up with the noise. The concrete people worried about not using concrete anymore. The top staff at Min DOT decided no more tinning in the twin city area. Also decided not to tine anyplace in the state and extended that moratorium. Prior to 1976-wet burlap or carpet drag 1976 Astro turf texturing plus transverse tining with 1 random effective spacing 1983-Astro turf plus transverse tining with 1 ½ random effective spacing on greater than 35 MPH designs 1995-Astro turf plus transverse tining with 5/8-1 random effective spacing for greater than 35 MPH designs 1998-99 Moratorium on tining to mitigate noise on concrete pavements.

The MN legislature wrote a state law requiring asphalt overlays then FHWA refused to pay for asphalt overlays over a brand new concrete road. Consultant recommended asphalt rather than diamond grinding to reduce the noise. Cost was irrelevant to the neighborhood group. The state needed to get a good texture without tining to solve the problem. They tried weighted down the astro turf to get the effect they were after, using gravel or rebars to provide the weight. They also tried broom textures. These methods ended up with particles on the surface, some of which will come off with the opening of traffic, but much of it is also taken off by the first winter snow plowing. The state has not adjusted cure application rate and they are measuring texture with the ASTM 965-87 sand patch test. It is important to remove the surface particles before testing. The contractor needs to change the astro turf more often to get a good texture. After removing the surface particles they may not get the texture you wanted with the test. The sand patch texture depth requirement-min. requirement of 1.00 mm for lot, 0.80 to 1.00 mm for lot-substantial compliance but requires contractor to amend the operation. Less than 0.80 mm for lot-requires diamond grinding and any test less than 0.70 mm requires diamond grinding of test section represented. A lot represents one days paving per driving lane. Each driving lane is an individual lot, lots are broken down into sublots representing 1000 lineal feet of pavement min. of 3 sub lots per day. The contractor shall complete all sand patch tests no later than the day following placement. How soon can they run it? They could do it the same day, but usually the next day. Is there weather restrictions on it? Cant do it in the rain. The agency shall verify contractors results as needed. Sometimes get problems with boogers not getting cleaned off well enough. Are we getting adequate skid numbers on these sections? The lowest numbers are on the asphalt section and they are lower than both of the concrete sections concluding that the concrete is still safer than the asphalt. With regard to the safety issues, shows they are still getting safer roads with non-tined concrete than with the asphalt. Average texture depth dropped 0.4mm after one winter plowing. The public doesnt seem to perceive any difference between the asphalt and the un tined concrete with regard to noise. Comments: Astro turf drag longitudinally was done on one Iowa road 20 yrs ago and still looks new and still has good skid numbers. Seems that FHWA looks at this issue differently within the different regions. Maybe FHWA could take the Marquette study and look into standardizing the measuring techniques for noise so that the states could share their findings re: techniques. Need to get the policy people to look at the bigger picture, rather than simply looking at the noise alonewhat about cost, safety, and other things. MCC should be the leaders in pushing for a uniform model-such as what Ted was saying.

Chicago area April17-18 for next meeting. Look for information is on the web.

A + B Bidding Round Table Discussion- State representatives

KANSAS-we dont use this method. Why not? Experimented with a couple of projects and apparently were not satisfied so dont do it.

MN-first project in 1992, three projects by 1994 had zero involvement with the issue. After talking to some people found that the amount of impact was $36,000 per day so they chose a lesser value of $10,000. It is very subjective trying to determine the impact on the user. Feels that incentives could be adjusted to make up for the issue of quality.

ILLINOIS-increasingly more of these and think that will be our direction for interstate projects. It seems there are more incentives for time completion rather than quality and the tech people are struggling with the policy makers and right now are trying different things combinations of mix design etc. Are trying to allow the contractor some tools to make things go faster.

NEBRASKA-only a few projects with it, not directly involved with that part of the process. Are looking more at other types of incentives so we get better quality. We are looking more at a quality issue, but where we have had a time issue we used this method of incentives to get things done. Doesnt think they will ever go all out probably more on the where necessary basis.

WISC-little with formal A+B Bidding, also not involved with the administration. Have done some incentive things with interstate jobs, but again, not a formal A+B. Question-what happens with the rest of your program? Contractors have only certain number of people so some of the other projects may sit and wait while they are working on the incentive jobs.

IOWA-doesnt get involved much, but the contract office does not do any A+B bidding. Although there has been some discussion, never really went anywhere. Seems the drop dead deadlines get more attention and seem to be used more often. However, when the contract office knows nothing about the contractor resources, etc. it makes sense that we should not be telling them how long it would take, but the contractor can tell better how long it would take to complete. Jim Grove thinks there needs to be some way to give the contractors incentives, but not sure this is the way. Experimenting with some window type incentives such as, determined a large job would take 2 years, but if they finish within one year get a bonus, etc. There is a series of key dates and they dont lose anything, but if they want the incentive they have to make the deadlines. Iowa found out with the A+B that changing the scope of the project can cause major difficulties. For example if they give 89 days, then the scope is increased considerably and they dont allow for that in changes the date. Really large contractors can often handle the changes, but not everyone can. A+B has worked well but needs some tweaking to get it to work better.

Question: Do we have state rules on bonus calculations or does each contract have a specific number?

KS-consistent across the board for each side of the industry both asphalt and concrete. Some are updated more often than others.

MN-road user costs are adjusted for each contract, we have a standard formula for big jobs, but they come up with the numbers then are adjusted.

MI-use the guess program so the per day incentive is calculated for each corridor based on the traffic volume.

IL-users costs are determined on a job by job basis but the incentives are about the same

NE-user cost if the job has to be open at a certain time and is based on traffic and user delay costs. Also have other formulas use for incentive based on quality of materials, etc. not all jobs have the lane rental fee so sometimes not really a penalty. Each job is different, but some things are the same.

WI-most are fixed date oriented and the numbers are figured using user costs etc. They dont think there is any standard formula, but there are similar ones. We do have models on the acceptance parameters for QC jobs that affect the incentives.

MI-some of the contractors like the A+B bidding because it requires the contractors to think through every single stage of the job and really consider what they can and cant do. That is probably great if there is competition, but that could be a problem if there are not enough competing contractors, could end up making the contracting agency pay more in the long run.

COMMENT-Someone thinks this is useful for certain jobs where time is a major issue, but not necessarily for every job.

Ted Ferragut thinks that the industry needs to be aware of states tightening up the time allotments so they dont have to pay the incentives, which could lead to less quality by virtue of the fact the contractors are trying to do the impossible. Arbitrary setting of the dates is the biggest scare. Really need to address the quality factor with regard to the time factor so the techniques can be considered together-how do we not slow it down yet ensure that we get good quality. Next challenge is to keep the Q in the equation with regard to Quality of life also.

Question: How many states have experience with more than 5 A+B jobs, MICHIGAN has done more than 5. How many of those have had quality problems?

IN-not really quality issues, but those who had good B portions also had good Quality.

MI-quality issues not the contractor issues. A lot of design work has been farmed out to consultants and the plans were abysmal. One set the plans were so laden with misinformation (a bridge was completely left off the plans) no plans would have been better. Need to ensure that all ducks are in a row before making it an A+B job.

Question: Are there any quality problems traced back specifically to the A+B bidding. The base issue was directly related to A+B and some other smaller issues lately. It seems the problems mostly come from the short weekend type projects, whereas the longer jobs (a year or two, saving some months, etc.).

MI - have decided they dont need to do A+ B all the time. There will be a lot of challenges to balancing time vs. quality issues.

Question-What is the definition of quality, strength, smoothness, etc.?

KS-QC/QA-currently uses strength and thickness will probably add air voids in a few years.

Question: How does curing figure into this early opening thing?

Comment: Maybe need to look at permeability-along with strength.

Comment:-suggested study sealed vs. unsealed joints. Has been some work on this issue from WI, OH. Within KS developed a serious problem with longitudinal spalling. The more thought about it, thought it started with diamond grinding along edges to put down stripes. Thought it was the diamond grinding, but in retrospect determined lack of air at top. Are just going with a sealed joint these days.

Comment: With longitudinal tining, joints have to overcome effect of deformed rebar.

Comment: Neoprene joint sealers performed better by far after about 4 years. Report will be coming out soon.

Future topics for MCC meetings? a. Sealed vs. unsealed joints-have someone collect the data available and get it ready for the next meeting. b. Cure approvals issue of such as white pigment, test procedures etc.-could we standardized any of those procedures? Curing compounds NTPEP involvement would be for general prequalification of manufacturer. c. More discussion about structural concrete on bridges, bridge decks. Some of the same technology could be used (fly ash, slag, silica fume, Permeability!!!) that is used in pavements. d. Group wants the future dates and locations established so that planning can follow for the participants. e. Move to send announcements to contractor groups in the state and surrounding areas where the meeting is being held to get more contractor participation. f. Revisit potential to down link the meetings to your state highway dept. city or somewhere to down link a satellite presentation so the meetings can be sent to one sight in each state to accommodate those who cant tavel. Fear of burning out people who are representing the states with the travel difficulties, etc. and is also a way to get some feedback from others. g. Suggested burning a CD of the minutes. This can be done if we identify the audience, but we already have them on the web. h. Some states participate in the program, but then trying to NTPEP-National Transportation Product Evaluation Program. Wants the group to take more interest in this program i. A+B Bidding vs. quality/performance/traffic delay

Consensus is that curing and joints are the two topics should be brought forward. Ride quality is also a topic that was considered for the theme of the spring meeting.

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