Apr 08
Apr 10
InTrans

2008 Spring National Concrete Consortium

Event Details
LOCATION

Baton Rouge, LA

VENUE

Hotel information not available

DATES

April 8, 2008 — April 10, 2008

TIME

Meeting begins at 7:45 a.m.

Event Contact
Denise Wagner
InTrans, CP Tech Center
515-294-5798
dfwagner@iastate.edu

Minutes

Welcome

Meeting began with a welcome by Sandra Larson, Iowa DOT. The goals of the TTCC and operational details of the pooled fund were discussed.

MCO Project

Jim Grove discussed the MCO project, overall lessons learned and related new research (PDF). Gary Fick presented the final MCO project deliverables (PDF). The Testing Guide along with a DVD of the AVA test, Coffee Cup test, and final report were also distributed.

States were asked to report on the implementation of the MCO report:

  • Kansas
    • Accelerated boil test procedure
    • Work with AVA continues
  • Oklahoma
    • Special provision for optional gradation
    • One contractor has approved mix design
    • Boil test is being considered
  • Ohio
    • Nothing implemented yet
    • Bridge deck cracking may result in some new testing
  • Wisconsin
    • Training session was held in February; also will have attendees at train-the-trainer
    • Training across the state in the next couple of years is planned
    • Will use AVA for trouble shooting problems
  • New York
    • Will be attending train-the-trainer and work towards training all of the contractors
    • MEPDG guide has taken precedence over the suite of tests.
  • Michigan
    • MCO project discussions have energized the process for quality control and improved working relationships with industry
    • Concrete levels as specified and then as constructed have been evaluated
    • Looking at the testing guide and how it should be used for Interstates vs local streets.
    • A statewide PCC pavement study of 130 pavements is being done to evaluate what factors contribute to premature failure. The suite of tests will be used to evaluate.
  • North Carolina
    • Instituted maturity into specs
    • Magnetic imaging devices into specs (2006)
    • Experimenting with AVA
    • Water/cement ratio via microwave
    • Automatic vibrator controls on pavers
  • Iowa
    • Changes had been implemented. MCO has served more as validation
    • Control charts as quality control have been used for a long time
    • Maturity – used regularly for quite awhile.
    • Vibration monitoring – used on most projects, required on large projects
    • Hyperpave – industry not really interested
    • Unit wave – already checked on larger projects
    • Hardened air, permeability, already checked on large projects
    • IMCP manual is a great tool, using it as part of a certification would be a great idea
  • Minnesota
    • AVA experience: helped us determine whether it really was ok
    • Compatible of ad-mixtures a big part
    • Chart has been impressive
    • Stay with 15 ft joints – Iowa uses 20 ft and that may be considered
    • Low paste content mixes (MI) are very interesting, not sure if MN too cold
    • Microwave testing – very positive
    • Dowel bar baskets – moving to 1 ft from the edge and thicker dowels
  • Indiana
    • Major effect is in a change in thinking – looking at concrete as a whole system.
  • Missouri
    • MCO project philosophy has been used to validate
    • Raise air content to 5%
    • Air loss validation project
    • Premature failure project: it appears to have very little entrained air
    • Optimized mixes as an option was used in 80% of last year’s projects
    • Bridge deck cracking – optimized mixes may be required
    • QC tool for maturity
    • Looking at adding the boil test to field test
  • Georgia
    • No drastic changes to procedures or mixes
    • More emphasis on training, doing tests correctly, verifying tests
    • Emphasis on verifying the mixes that are specified. Are mixes performing like they should?
    • Dowel bar: 15 ft spacing; inch and half dowel bars, cut back on joint sealing
    • Only one source for ASR and contractors are not interested
    • Basic mixes seems to be working
    • CRC pavement is now being planned
  • Louisiana
    • Manual is great verification
    • Probability testing – no set standards.
    • It is becoming mandatory to have set permeability testing.
    • LSU has a co-efficient thermal expansion study on both old and new pavement projects to look at variation
    • May consider 15 ft joint spacing (from 20 ft.) MEPDG seems to recommend 15 ft
    • Flexural testing as part of mix design approval should be considered, but hard to do quality assurance.
    • Hyperpave: doesn’t seem to be a big interest.
    • Superior air void system isn’t as critical so LA won’t use AVA until machine is improved
    • Calorimtry is of interest – incompatibility when mix changes

Other Pooled Fund Projects

Steel Finder Cart – Kansas

  • Mix scan device (MIT developed)
  • Measures the depth to the steel reinforcement
  • Multisensory version – shows when the bar is skewed.
  • Working to develop 3rd sensor that will tell you if its skewed horizontally or vertically

Future plans: Mount it on a contractor machine to verify it can tell in real time if bars are being inserted correctly or longitudinal joints
Questionnaire from KsDOT being developed: What does industry think? Would they use it?

IMCP Manual (PDF)

    • What is needed before construction: Fresh properties (uniformity, workability, air content, no segregation)
    • Field verification:
      • Production mixes different than lab mixes
      • Test mixture properties (before and during construction)
      • What is needed after construction: Hardened Properties (Durability)
      • Construction challenges
        • See PowerPoint for research recently completed and being proposed to fill some gaps

CP Road Map Mix Design and Analysis Track Pooled Fund (PDF)

  • Goal: mixtures that are consistently long-lasting, constructible and cost effective
  • Subtrack: Tests needed
    • CTE
    • AVA
      • Field temperature monitoring (calorimetry)
        • Education needed between calorimetry and maturity
      • Foam index (Indiana is taking lead)
        • Permeability and Torrent (Rilem is going this way)
      • Boiled water test
        • Fairly old test , but what are the limitations, restraints, and positive elements
      • Micro-deval abrasion test
        • Virginia has done it – should it be given some visibility?
      • Foam drainage
      • Rheology test for pavement mixtures
      • Mix proportions:
        • Good details on mix proportions from lab, but need to measure that what is coming from the plant is also being placed in the field.
        • Goal: a tester (“gun”) that will show mix proportions coming out of back of paver
      • Field temperature monitoring
      • A formal method statement needs to be developed for submission to AASHTO and ASTM
  • Subtrack: Relationships, models and computer programs. Model doesn’t have to mean computer model. It could be the “rule of thumb” used, i.e. 1% air = 5% less strength
    • Interaction Hyperdoc: Tools that show what is happening i.e. IMCP manual
    • Air void system – minimum requirements. 1952 “rule of thumb” is still being used; is 9% still valid?
    • Paste content and shrinkage
    • Working temperatures
    • Combined gradings
    • Long term monitoring: what should be monitored?
  • Subtrack: Specifications. We only want to pay for what was ordered, but how is that determined?
    • Check sheets
    • Guide specification
    • Generic admixture specification
  • Subtract: Communications
    • Field trials – new tests
    • Field trials – new models
    • Field trials – new specifications
    • Training materials
  • Budget
    • Testing: $200,000
    • Develop models: $300,000
    • Write specifications: $200,000
    • Communications: $200,000
    • Project oversight: $100,000
  • Funding
    • Pooled fund $500,000 (11 states $15,000/year for 3 years)
    • CP Tech Center’s Cooperative Agreement: $500,000
  • Discussion:
    • What do we want to do first? Results of questionnaire (PDF)
    • What needs to be measured in concrete mixtures?
      • Properties to predict durability (5)
      • Water content and w/cm (3)
      • Rheology (3)
      • Air entrainment at the paver (2)
      • Curing (2)
      • “Emotional” state of being (2)
      • In-place strength test method
      • Real time evaluation
    • Tests (suggested and priority voting)
      • Calorimetry (12)
      • Rheology (10)
      • Other air tests (7)
      • Mix proportions (7)
      • Foam index (6)
      • Foam drainage (3)
      • Boiled water (3)
      • Unit weight/density (2)
      • AVA (0)
      • CTE (0)
      • Segregation (0)
      • Finish (0)
    • Models (suggested and priority voting)
      • Air needs (16)
      • Paste & shrinkage (11)
      • Long term monitoring (9)
      • Working temp (7)
      • Interaction doc (6)
      • Combined grading (5)
    • Specifications (suggested and priority voting)
      • Guide sheets (23)
      • Check sheets (10)
      • Generic admix (1)

 

COMPASS Demonstration (Mauricio Ruiz)

Design and Proportioning of Concrete Mixtures for Pavements (PDF)

  • An easy-to use and reliable method to design and proportion robust concrete paving mixtures is critically needed!
  • Guide Document: EB-401: Design and Proportioning of Concrete Paving Mixtures
  • Industry is taking the lead, but with input and involvement from FHWA, DOTs, CP Tech Center, academia…
  • Review panel has been assembled to review and comment on EB401
  • Most of the pieces are already here… ACI 211.1 and PCA volumetric methods, IMCP guidance, MCO, Shilstone, COMPASS?
  • Guidance ultimately incorporated in training efforts!

Evaluation of Test Methods for Permeability (Transport) and Development of Performance Guidelines for Durability (PDF)

  • Motivation for the study:
    • Concrete specified and placed – prescriptive specifications
    • Shift from prescriptive specifications to end result or performance based specifications.
    • PRS: Slowed by a lack of testing procedures, especially relating to transport
    • Replace prescription with performance requirement for corrosion resistance
  • Link between durability and transport
    • Concrete specified and placed – prescriptive specifications
    • Each potential durability issue can be related in part to water penetration
    • To specify more durable concrete, tests are needed: Qualify the resistance of the concrete to water (or aggressive fluid) penetration.
  • Project objectives
    • Develop test procedures to directly evaluate the transport properties of concrete and relate these to anticipated performance with the use of exposure conditions
    • Evaluate existing transport test procedures and develop new, or improve test procedures
    • Correlate transport properties and existing ‘durability’ tests.
    • Develop guidelines to relate permeability, exposure conditions, and field performance for use in specifications and quality control
  • Preliminary conclusions:
    • Mixture with “very low” (975 Coulombs) chloride ion penetrability (ASTM C 1202) has a high chloride ion diffusion coefficient (SF12/0.63)
    • Mixtures with “higher” chloride ion penetrability (ASTM C 1202) has a lower chloride diffusion (SL23/0.40 vs SF12/0.60)
    • The RCPT does not rank mixtures in the same order as the chloride ion diffusion.
    • Further study should show:
      • Measurement of water absorption using a semi-automated procedure
      • Significance of sample orientation
      • Detailed analysis of water penetration depth at early ages

Taking the Next Step Forward: Sustainable Green Highways (PDF)

  • The present system does not reward the contractor for good durability. The responsibility is assumed by the specification writer.
  • “Resistance to severe weathering and sulfate waters is determined largely by impermeability. . .”
  • Aggregate size in relation to concrete
  • Greensboro, NC, circa 1985. Job redone in one weekend
  • Field testing to watch:
    • Hanson – Iowa DOT: Correlating cores and durability.
    • Staton – Michigan DOT: Comparing strength gain different cementitious over 1 year.
    • Montney – Kansas DOT; Permeability – chloride v ASTM C 642
  • Chloride ion testing
  • Air entrainment data: Essential testing is needed
  • GOING GREEN and DURABLE!!

Fall Meeting

Fall meeting will be September 23, 2008 in Minneapolis/St. Paul, Minnesota.

Wednesday, April 9, 2008 – NC² theme: Sustainability in Concrete Construction

NC² Business Meeting

  • Bylaws (PDF), Mission Statement, Election of officers for the governing body of NC² (PDF)
  • Slate of 9 officers and appointment positions for the Executive Committee were presented:
    • Chair – J. Staton, Michigan DOT (term expires 2009)
    • SAR
      • Region 1 – Mike Brinkman, NYDOT (term expires 2009)
      • Region 2 – Christopher Abadie, LADOT (term expires 2010)
      • Region 3 – James Parry, WisDOT (term expires 2009)
      • Region 4 – Clayton Schumaker, NDDOT (term expires 2010)
      • Contractor – Dan DeGraaf, MCPA (term expires 2009)
      • Supplier – Phil Graham, BASF (term expires 2009)
      • Academia – Larry Sutter, MTU (term expires 2010)
      • At-large – Tom VanDam, Applied Pavement Tech. (term expires 2010)
  • State Report Coordinator – CP Tech Center
  • Meeting Notes – CP Tech Center
  • Secretary/Treasurer – CP Tech Center
  • NC²/TTCC Liaison – Sandra Larson, Iowa DOT
  • FHWA ex-officio – Max Grogg, FHWA Iowa Division
  • Steve Tritsch moved, Jennifer Distlehorst seconded to accept slate of officers. Approved.
  • NC² and TTCC relationship overview (Powerpoint: Day 2B Staton)
  • Each group has a separate function, but has a great deal of overlap and will work closely together. As manager of both groups, the CP Tech Center will be the catalyst to keep the groups focused and moving forward.

Sustainability

Dominique Lueckenhoff, EPA Region 3, Green Highway Partnership (Day 2C Lueckenhoff)
How the Goal and Mission of the GHP are being implemented was presented.

Broad Based Partnership

  • Academia, Industry and Trade Organizations, Counties & Municipalities, Federal and State Government Agencies, Environmental NPOs
  • New practices, new technologies under existing requirements = many skeptics. We need more case studies, more applied research, showing these approaches work.
  • Roadways instead of being the polluter are the treatment center
  • Recycle & Reuse: eventually nothing will be virgin anymore.
  • We need to SYNC our systems not try to SINK each others systems.
  • Look at opportunities to leverage research dollars – integrated planning cycles would be great, but are unrealistic. What types of strategic planning can be done for win-win?
  • Not just green highways, but also green streets. Look ahead at using the technology for the future – streets frequently become highways.

Leveraging of Knowledge, Experience, & Resources

  • Knowledge
    • ACPA, Villanova Research (Determining the parameters of
    • Pervious/Porous Pavements for input into a BMP Decision Support Tool)
    • MOA with NRMCA Green star program – LEED for readymix industry. Takes requirements for compliance and drops it in to existing business model. EPA will be looking at systems rather than “widgets” – environmental training for self-governing.
  • Experience
    • Maryland SHA Green Highways (A Watershed Approach to Stormwater Management)
    • District of Columbia DOT (LID Standards)
    • Prince Georges County (Gateway Projects Program)
  • Resources
    • Anacostia Watershed Grants (District of Columbia, Prince Georges County)
    • EPA ORD – RARE Project: Use of Steel Slag to remove Phosphorus

Doing Business Differently

  • EPA grant funds awarded to DOTs
  • Working to break down regulatory silos within EPA and other Regulatory Agencies
  • Watershed Resource Registry Pilot
  • Increasing regulatory predictability & flexibility
  • Corporate Stewardship Agreements
  • CEP Team Strategic Conservation Assessments for Transportation

Leaving Things Better Than Before

  • Examples of Green Highway Practices
    • Bioretention
    • Porous Pavements
    • Environmentally Friendly Concrete
    • Forest Buffers
    • Restored and Stormwater Wetlands
    • Stream Restoration
    • Wildlife Crossings
    • Soil Amendments
    • Diesel Hook-Ups
    • 100-Yr Pavements
    • Use of Recycled/Reclaimed Materials
    • Cool Pavements
    • Alternative Bio-Fuels

Larry Sutter, Michigan Tech; Concrete Sustainability: A Vision for Sustainable Construction With Concrete in North America (PDF)

  • Sustainable Development: Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
  • Alternate Definition: Making decisions based upon the “triple bottom line” that includes social impacts, environmental impacts, economic impacts.
  • ACI Strategic Development Council created the Sustainable Development Initiative about one year ago. Their charge:
    • Develop the guiding document leading to a road map to sustainability for the concrete industry
  • A series of 5 workshops were held discussing and shaping the document
    • One of the committees of the workshops was Environmental Footprint/Metrics
      • Document the improvements made in the past 50 years regarding GHG emission, embodied energy, and water use in the concrete industry
      • Isolate the segments of the industry where the largest gains remain to be made
      • Quantify the magnitude of those gains and the strategies/research/ technology required to achieve them
      • Set a target date to achieve milestones, which will dictate the rate of change needed
  • Other Issues
    • IEA data consider cement only, not concrete
      • Reflects increased use of blended cements outside U.S.
      • Doesn’t capture impact of increased use of SCMs in concrete in the U.S.
      • Structure of the U.S. cement and concrete industry is different from most major bench-mark markets in the world – less vertically integrated, makes it difficult for cement companies to lead
      • U.S. concrete industry may be uniquely positioned to have a larger direct role in (and responsibility for) CO2 reduction, vs global benchmarks where cement industry drives progress
    • BHAGs – big hairy audacious goals. They are do-able, but not easy and not cheap.
      • Challenge to get back to 2005 levels due to increase in consumption
      • To get back to 1990 will be VERY difficult
      • The industry is of the mindset that we don’t have enough information to set goals. Targets are set, but by 2010 we need to have information to set realistic goals.
      • Embodied Energy: Reduce by 20% by 2020
      • Water Use: Reduce by 50% by 2020. Zero Discharge by 2050
  • Consensus: By 2010 we need to set targets for 2030 to:
    • Reduce the carbon footprint per unit of concrete and concrete product produced.
    • Reduce the total annual carbon footprint for all concrete and concrete put in place.
    • Substantially improve the environmental footprint of concrete with regards to embodied energy, water conservation, water quality, air quality, recycling and reuse.
    • Substantially improve the sustainable characteristics of new structures through the efficient and effective use of concrete in construction to take full advantage of concrete’s attributes, and adopting specifications that facilitate innovation in product design.
    • Establish education and outreach goals by market segment, with funded work plans for 75% of industry sectors.
  • How do we get there
    • Industry is not willing to take on the task by themselves. They need stakeholder support – demand driven change.
    • Federal and State Highway Agencies need to lead the issue of sustainability
    • Unilateral changes to affect sustainability
      • Decrease the use of portland cement
      • Increase use of SCMs
      • More recycled materials
      • Development of new sustainable-design tools
    • New design tools needed
      • What is the CO2/embodied energy in a mile of pavement? How is it measured?
      • What are the CO2/embodied energy in different design/materials options?
      • How can the CO2/embodied energy be lowered through design/materials choices?
      • Eventually “triple bottom line” (societal impact, environmental impact, and economic impact) engineering cost estimates?
  • Discussion: In terms of improvement in cement production, to what degree was nanotechnology discussed as a strategy for reduction?
    • Larry Sutter: Nano was not discussed much. Mostly other materials, SCMs.
    • Tom Cackler: Nano appears to have lots of opportunity for reduction. The CP Tech Center held a workshop together with NSF last fall on nano for cement and concrete. The proceedings are available on the CP Tech website (www.cptechcenter.org)
    • Larry: Perhaps nano falls into the new concretes area, not sure it works with existing types of concrete.
    • Larry’s personal BHAG: Synthetic aggregate.
    • Jim Shilstone: You are underestimating SCMs.

Jeff Melton, University of New Hampshire: Recycled Materials Resource Center (PDF)

  • 39 research projects completed to date
    • Project 1: Mitigating Alkali Silicate Reaction in Recycled Concrete
    • Project 2: Using Lithium to Mitigate ASR in RCA Concrete
    • Project 38: Recycled Concrete Aggregate Concrete Pavement Performance Survey Outreach for the Federal Highway Administration National Review
  • Guidance Documents
    • IMCPCP (HIF-07-004) pg. 44 The recycled aggregate should be taken from a pavement that is known not to have experienced materials-related problems.
    • SAMARIS SAM-06DE05 pg. 129-130 …recycled aggregates from concrete pavements can be used with the exception of those originated by freeze-thaw causes, alkali/aggregate reactions, sulfate attacks or the action of ice melting salts.
  • What to do?
    • Scrap the guidance documents?
    • Only used non-distressed aggregate in new PCC?
    • Just use distressed aggregate in unbound applications?
    • What is the best value?
  • What is the cost:
    • Is the cost in dollars per lane mile?
      • What about maintenance?
      • What about environmental effects?
    • How does cost play in project bidding?
      • Where is incentive in low bid process?
      • How do other partners factor into awarding projects (Green Highways)?
    • What is the incentive?
      • What is the incentive to use RCA?
      • Right now, incentive points to u bound applications
      • However aggregate supply, costs and other factors (mandates?) may come into play.
  • Research
    • Need to do research now to be prepared for the future
    • Look at ASR, D cracking, mix design (water demand), old mortar fraction, etc.
    • Also look at life cycle cost analysis to understand true project costs.
    • Project 23 LCA Tool PaLATE
      • LCA tool specifically designed to compare natural versus recycled material aggregates
      • Considers maintenance as well as construction costs
      • Also considers environmental effects
      • Can help define “true” cost of a project

Jason Harrington, FHWA: Environmental Stewardship

Tom Van Dam, Michigan Tech; Developing an Approach for Sustainable Concrete Pavements Through the CP Road Map Concrete Pavement Sustainability Track (PDF)

  • With the increase in emphasis on sustainability and the environment, the CP Road Map Executive Committee designated the Advancements in Concrete Pavement Sustainability and the Environment as a full track on September 11, 2007
  • Track mission : Through a commitment to sustainability, conduct research and technology transfer that transforms the way concrete pavements are manufactured, designed, constructed, maintained, rehabilitated, restored, and recycled to improve economic, environmental, and societal benefits and acceptance .
  • Challenges and Opportunities
    • Increase the use of fly ash, ground slag, and other supplementary cementitious materials
    • Increase the use of recycled or industrial byproduct materials in concrete and concrete pavement systems
    • Further reduce CO2 per yd of placed concrete
    • Optimize pavement design to use less concrete
    • Increase pavement longevity through conventional and innovative means
    • Optimize surface characteristics to reduce noise, heat, lighting costs, and air pollution while improving fuel efficiency
    • Enhance surface drainage
    • Improve business processes to increase efficiency while minimizing waste
    • Rehabilitation of material extraction sites for recreational uses
    • Adoption of a rigorous LCA process with usable software tools to accurately account for various economic, environmental, and societal impacts
    • Implement strategies to optimize use of readily available materials
    • Demonstrate that sustainable solutions are at their core good economic, environmental, and societal solutions
      • Measuring Progress Toward Achieving Goals
    • Much more difficult than it would seem
    • Metrics might include the normal suspects
    • Embodied energy, global warming potential, others?
    • Governance issues must also be considered that provide “credit” for sustainable solutions
    • A number of gaps exist at this juncture, and it is up to us to fill them in
      • Ideas of Initial Projects
    • Quantify and validate assumptions of environment, economic, and social impacts
    • Organize and conduct a conference on sustainability of concrete pavements to increase our awareness of how economics, technology, and legislative/policy initiatives interact
    • Select two research projects that address specific technology advances that improve concrete pavement sustainability
    • Recommend a project that assesses an environmental property in place (such as reflectance or ability to clean the air)

Tim Cost, Holcim; Performance Cements: Focus on Sustainability (PDF)

  • Formula for sustainability:
    • Minimize the clinker content in concrete
    • Minimize the transport of materials
    • Maximize the beneficial re-use of byproducts
    • Maximize use of materials with low associated CO2 emissions
      • Blended cements versus separate components
      • Limestone in cement
      • Observations from concrete data
    • Reactivity of 8-10% limestone cements from plants “A” and “B” with Class C ash and water reducer is clearly better than for non-limestone cements from those plants in gravel mixes
      • Very good fly ash/admix response for the limestone cements regardless of the aggregate
    • Set time effects slightly longer for plant “A”, similar for plant “B”
    • Strengths generally higher with limestone cements at all ages
      • Sustainability & specifications considerations
    • 10% limestone is a realistic level under C 1157
    • Up to 4 times the reductions of CO2 emissions, energy use, use of resources, solid wastes
    • SCMs can still be used in concrete to the maximum extent possible with any cement
    • 10% limestone is a realistic level under C 1157
    • Should a special category for higher limestone cements be included in US specifications?
  • Conclusions & recommendations
    • Performance in concrete of ASTM C 1157 limestone-modified portland cements with 8-10% limestone content is equivalent to or in some cases better than that of traditional non-limestone cements:
      • Strength development overall is at least equivalent
      • Strengths in combinations with Class C fly ash and typical water reducing admixtures may excel, especially with gravel aggregates.
      • Some plastic concrete properties are improved.
      • Durability performance as indicated by common test methods is equivalent or better.
      • Potential environmental and sustainability influences of cements containing 8-10% limestone are significant
      • Barriers to the use of higher limestone content cements should be removed:
        • State DOTs should consider acceptance of ASTM C 1157 cements.
        • State governments and state and local building officials should assure that modern building codes that recognize ASTM C 1157 are in place.
        • Provisions for special categories of higher limestone content cements should be considered by US specification organizations (ASTM, AASHTO).

Gary Fick for Jim Duit, Duit Construction: Paradigm Concrete Recycling (PDF)

  • Recycled concrete
    • Whatever steel goes into PCC must come out for recycle
    • Aggregates have a big impact on the cost of recycling
    • Some base material under PCC will get into the recycle mix
  • Aggregate base
  • Open graded base
  • Cement treated base
    • Temporary pavements
    • Two-lift construction
  • Additional uses
    • Shoulder-up material
    • Road gravel – counties, etc.
    • Pad line
    • Undercut materials

Ben Franklin, Headwaters, Maintaining and Improving Marketability of Coal Fly Ash (PDF)

  • What is the future of coal fly ash utilization in a mercury controls world?
  • What other business and regulatory trends may affect ash utilization?
  • Examples of two challenges
    • Effects of emissions control technology installations (especially for mercury removal)
    • Other ash quality issues
  • Examples of two opportunities
    • “Green Building” trends
    • Carbon trading
  • Challenge: Mercury Controls
    • One approach to reducing mercury emissions from power plants is injection of powdered activated carbon sorbent into flue gases
    • Too much carbon in fly ash can interfere with proper air entrainment of concrete
    • Numerous strategies exist to protect fly ash quality
  • Challenge: Other issues
    • Fly ash has successfully managed quality issues resulting from emissions control requirements before, such as impact of: Low NOx burners and fuel switching
    • Ash quality improvement technologies exist
    • Carbon reduction or removal
    • Reburning, air or water separation, chemical fixation
    • Particle size management
    • Mechanical processing
  • There are no bullets – magic or fatal.
  • Ash marketability depends on interaction of numerous economic factors:
  • Discourages utilization:
    • High capital expense to improve or maintain quality
    • High costs to store material prior to use
    • Rising costs of transportation to deliver material to markets
  • Encourages utilization:
    • High disposal costs
    • Rising costs / decreasing availability of competitive material (eg. cement)
    • Increased recognition of performance benefits
    • Incentives for green building

Leif Wathne, ACPA: Industry Perspective on Green Highway Partnership (PDF)

Green Highways Initiative

  • In 2005, EPA started the Green Highways Initiative as an instrument for coordinating environmentalism and transportation
  • Focus on demonstrating and ensuring that sustainable practices and economic success can go hand-in-hand!
  • Although cement is a relatively energy and CO2 intensive material to manufacture… cement manufacturing accounts for only 1.5% of US CO2 emissions
  • Includes CO2 emissions of cement manufacture for all concrete and masonry uses (not just pavement)…
  • Concrete most widely used material on earth, apart from water (www.wbcsd.org)
  • Cement industry has lowered the amount of energy required to make a ton of cement by 33% since 1972
  • CMS program pledge another 10% by 2020
  • 92% of paving concrete is comprised of materials that have a low CO2 footprint…
  • All these materials are available/manufactured here in the US, often locally
  • Overall sustainability benefits associated with use of concrete for pavements dramatically outweigh the impact of the cement manufacturing process…
  • Longevity means
    • Less-frequent reconstruction
    • Lower consumption of raw materials (cement, aggregates, steel)
    • Lower energy consumption
    • Raw material processing
    • Rehab and reconstruction
    • Congestion
    • Reduction in pollutants (manufacturing, construction, congestion)
    • Lives saved
    • Rigid structure, profile durability
    • Infrequent construction zones
  • All of these translate into real economic benefits
  • Summary
    • Concrete pavement is the sustainable choice!
    • Lower overall energy footprint!
    • Long lasting and renewable
    • Less fuel and CO2 to construct
    • Less resource intensive
    • Better fuel economy – less CO2, NOx and Sox
    • Urban heat island mitigation, better visibility
    • Use of industrial by-products
    • Opportunities for improved water quality!
  • Conclusion
    • North American concrete paving industry strongly supports sustainable development
    • Concrete pavements are the clear choice for environmentally sensitive and economically sustainable roadways – key is LONGEVITY!
    • ACPA published a special report on Green Highways, in October 2007. Available at: www.pavement.com

Tour arranged by Louisiana Transportation Research Center (PDF)

  • John James Audubon Design-Build Bridge Project
    • 1583’ Cable-stayed main-span
    • Twin planes of cable-stays (galvanized strand)
    • H-shaped pylon with double strut above deck (515’ above low-water elevation)
    • Drilled-shaft foundations (post grouted)
    • Main pier footings at low-water level
    • Substantial amount of construction to be land-based from trestles.
    • The longest cable-stayed span in North America
  • Thursday, April 10, 2008
    • State reports and roundtable discussion (Jim Grove/Tom Cackler)
    • Discussion of regional subcommittees (Wouter Gulden)

Wouter Gulden: SCAN (Southeast Concrete Alliance Network) (PDF)

  • The objectives of this organization are:
    • To develop uniform regional specifications for concrete pavements for highways, local roads, and streets.
    • To promote reciprocity of material specifications among the member states.
    • To develop a comprehensive information sharing process.
    • To establish a coordinated regional research effort.
    • To promote quality designs and construction practices.
    • To hold an annual forum for sharing information and to present new technology and research efforts concerning portland cement concrete pavements and its components for highways, local roads, and streets
    • SCAN has been modeled after NC²
    • SCAN participants have noted importance of networking; hearing what other states are doing – both positive and negative aspects of technologies being used
    • SCAN has noted that uniform specs is a hard sell
    • They are struggling for regional research effort
    • Should SCAN and NC² have a combined meeting next April? NC² Executive Committee will discuss and look into feasibility.

Missouri DOT – Brent Trautman: End Result Testing – PCCP (PDF)

  • Report on End Result Testing being done in Missouri looking at:
    • Durability test on field samples
    • Minimum testing frequency
    • Number of specimens
    • Pay factor schedule
  • End Result Testing– PCCP Continue field testing in 2008
  • Determine permeability, permeable voids and air void structure on laboratory and field tests
  • Only sample concrete behind the paver
  • Utilize 4” x 8” cylinders for compressive strength
  • Perform AVA testing on laboratory and field tests
  • Start monitoring projects constructed in 2007

Kansas DOT – Jennifer Distlehorst: Report on AVA Testing (PDF)

  • Hardened air test always different
  • AVA has limitations but better than anything else we presently have

Michigan DOT – Larry Sutter: Impact of Hydrated Cement Paste Quality and Entrained Air-Void System on the Durability of Concrete (PDF)

  • Objectives:
    • Concrete mixtures have undergone numerous changes in recent years
    • As the mixtures have changed, the research linking air-void system parameters to performance has not been updated
    • The research used to establish the current air content requirements was predominately conducted prior to 1970
    • Changes that have occurred (e.g. lower w/cm, use of SCMs, synthetic AEAs) affect not only the quality of the hydrated cement paste but also the characteristics of the entrained air-void system
  • Summary:
    • New baseline information regarding the hardened cement paste systems in today’s paving concrete
    • Project will provide valuable information to help establish the effectiveness of new testing methods
    • Provide information to augment and support the mix design track being discussed

CP Tech Center – Paul Wiegand: CP Road Map (PDF)

  • Discussion on CP Road Map and its objectives:
    • Pooled Fund #1179: Champion the CP Road Map
    • Develop and Maintain the Research Database
    • Facilitate Collaboration for Funding Research
    • Support Communications through Website; Targeted Publications; Newsletters, etc.
    • Organize and Support Priority Track Leadership Groups
    • Develop Track Framework Documents Identifying Priority Research Projects
    • Identify Potential Funding agencies for Priority Projects
    • Plan and Facilitate Track Leadership meetings for the Priority Tracks
    • Pooled Fund Cost
      • 4 years
      • $25,000 per year recommended
      • $5,000 per year minimum
    • Benefits
      • Support the Road Map
      • Involvement with the TAC
      • Eligible for Road Map Executive Committee (2 representatives) with full funding
      • Provide recommendations on Track Management Tasks

Identification of how to bring needs and problem statements to the attention of TRB, NCHRP and the AASHTO /SCOR committees for funding

  • What is mechanism to move research needs forward with subcommittees?
  • Members of NC² were encouraged to make their affiliation with national agencies known, and to be the conduit for research information between NC² and their committees.
  • Most of the Associations have a member either on the committee or attending meetings.
  • Recommendation to have a half-day workshop on CP Road Map. Invite presentations and papers and publish this as a TRB workshop addendum. Papers presented get referenced and exposure.

General Discussion

  • State reports on research and needs were not part of NC² meeting. It would take a lot of time, but interest was expressed by many participants. Real value in hearing what other states are doing or planning to do.
  • Selected longer state reports with new/completed research is beneficial.
  • When a state is having problems with a technology, hearing how others are dealing with similar issues is of value.
  • Researchers in the audience may develop research or incorporate problem areas into existing research and work to solve the problems.
  • Tom Cackler: There is a need to develop uniform regional specifications for concrete pavements for highways, local roads, and streets.

Next Meeting

  • NC² fall meeting will be September 24-25 (TTCC September 23) in Minneapolis, Minnesota.
  • Field trip on 35W bridge.
  • Perhaps field trip on MnROAD activities.
  • Reminder the theme of NC² needs to be on concrete, not just pavements.
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