seminar effectiveness discussion - transportation

AASHTO Joint Technical Committee on Pavements April 12 and 13, 2007

Irvine, CA The AASHTO Joint Technical Committee on Pavements (JTCoP) met on April 12 and 13, 2007 in Irvine, CA. A meeting open to visitors was held on April 12, 2007 and a closed meeting for JTCoP members only was held on April 13, 2007. A list of attendees present at each day of the meeting is included as Attachment 1 to these minutes.

The following are minutes from the April 12, 2007 JTCoP meeting.

Seminar Effectiveness Discussion The following is a summary of discussion regarding the effectiveness of the ME-PDG seminar held on April 10 and 11, 2007.

Andy Gisi (KS) – Liked the software demonstration and the discussion on how to change defaults and other intermediate files was very useful and provides the states the flexibility they need to modify the files for their conditions.

Michael Murphy (TX) – Felt the seminar was very effective and addressed many of the comments/concerns that states had. Liked the discussion on changing the intermediate files to adjust for states typical values. They hope to work with other states to address the design of low volume roads.

Danny Dawood (PA) – For low volume roadway design for PCC, the software can be used for thicknesses over 6 inches but the models have not been calibrated for the low traffic volumes. For HMA low volume designs, the MEPDG does not provide any substantial benefit and recommend the use of other less input intensive programs. MEPDG will work but too many inputs required. The MEPDG considers the pavement structure and not surface treatments.

Judith Corley-Lay (NC) - Doesn’t like the idea of having two design procedures. She was happy to see that presenters included a discussion on the limits of the calibration.

Ed Harrigan (TRB) – Part 4 of the 1-37A documentation was recommended to be removed based on the 1-40 Panel and reference should be made to the NCHRP 1-32 project which developed a design catalog for low volume roads.

Bill Farnbach (CA) – Limit use of Level for forensics. CA doesn’t have Level 1 data for inputs cataloged and material sources are too variable.

Jeff Dean (OK) – Would like to see section added to identify intermediate files and include in manual. Gregg Larson said the file format for the intermediate files could be created but it would take more time than was available on the current contract. He recommended that this be addressed with the release of the AASHTOWare version 2.0 of the software.

Chris Wagner (FHWA) – Will contact Gregg to see if he can sit with him for a day to develop one-pagers for some of the more critical intermediate files.

AASHTO Joint Technical Committee on Pavements April 12 & 13, 2007 Irvine, CA

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Bill Farnbach (CA) - Felt that the one-pagers for intermediate files should not be included in the manual and should be made available to the expert users only to prevent the files from being corrupted by novice users.

Michael Murphy (TX) – Wanted more guidance provided on the impact of shallow bedrock and how accurate the depth should be.

Gregg Larson (ARA) – Best way to determine the average depth to water table is to use the State Agricultural Service data which has values for all of the counties within a given state.

Comments on MEPDG User Manual The JTCoP held a ballot to approve the draft MEPDG User Manual document developed under NCHRP 1-40. The ballot was approved with 81% of the committee voting to approve the guide. A number of comments were raised in the ballot. During the meeting the comments raised were discussed by the committee to determine any action that should be taken to modify the draft document before it is sent forward to ballot to the AASHTO Subcommittees on Design and Materials. The results of this discussion are included in Attachment 2 to these minutes.

Motion: Judy Corley-Lay (NC) motioned to incorporate all changes discussed to the ME-PDG User Guide (see Attachment 2). Larry Lockett (AL) seconded the motion.

Voting Results: Yes - 18 No - 0

The motion passed with 100% concurrence

Comments on Proposed Friction Guide The JTCoP reviewed the Guide for Pavement Friction developed under NCHRP 1-43. Comments were received by committee members and reviewed during the meeting to determine if they were persuasive enough to modify the guide before balloting for approval by AASHTO. The changes recommended were limited to editorial changes as defined in Attachment 3 to these minutes. It was discussed that the NCHRP panel worked very hard to develop the guide document to remove any policy on friction standards. The panel recommended that these policies should be developed within each state agency and not contained within the AASHTO guide.

Mike Murphy (TX) distributed a copy of the guidelines used in Texas DOT to manage the friction program.

Motion: Judy Corley-Lay (NC) motioned that the JTCoP approve the Guide for Pavement Friction modified as agreed in the meeting as an AASHTO publication. Mike Pologruto (VT) seconded the motion.

Voting Results: Yes - 18 No - 0

The motion passed with 100% concurrence


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Action Item: Jay Bledsoe (MO) will work with Mike Murphy (TX) to modify the document as agreed. In addition, Jay Bledsoe (MO) will draft a cover letter to include with the ballot for the Subcommittee on Design which will include an endorsement from the AASHTO Legal Affairs Subcommittee.


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The following are minutes from the April 13, 2007 JTCoP meeting.

ACPA Pavements4Life Website The reaction to the changes made by ACPA to the Pavements4Life website was discussed. The following is a summary of comments raised during the meeting:

Concerns were raised over the portion of the website that is designed to assist visitors to the website to write their state legislative representatives to encourage the use of concrete pavements. Although this was a concern, nobody at the meeting had been contacted as a result of visitors to the website.

Many states expressed concern that the ACPA website could generate a reaction similar to other industry websites which promote the use of a particular material or product. Some states expressed that they had to defend their engineering decisions in the use of materials to design, build and maintain pavements as a result of these websites.

The committee felt that they had adequately expressed their concerns regarding the website in the December, 2006 JTCoP meeting and that ACPA did modify the website as a result. In general the committee felt that expressing any additional concerns would not be productive. It was suggested that states should work together with their local ACPA Chapters to discuss any concern regarding the website.

Motion: Larry Lockett (AL) motioned that the JTCoP will do nothing as a group to react to the ACPA Pavements4Life website. Jay Bledsoe (MO) seconded the motion.

Voting Results: Yes - 15 No - WY, CA, CO

The motion passed with 83% concurrence. It was suggested that each state consider informing their Chief Engineer of any concerns regarding the website and to write ACPA directly if they had any specific concerns.

It was suggested that Bob Templeton of the National Partnership for Highway Quality be contacted to make him aware of the website.

Committee Operations The committee members present at the meeting discussed the need to better understand operating procedures of the JTCoP and to recommend additional operating procedures where necessary to better define the manner in which the committee needs to conduct business. It was suggested that the committee operate much like a Technical Section within the AASHTO Subcommittee on Materials, however, there was a strong desire to limit detailed publication review during committee meetings.

It was discussed that a process needs to be in place to maintain the guide documents and that the committee should review the process in place to maintain the AASHTO Geometric Design of Highways and Streets (green book) as a model.


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Several comments were raised addressing the committee’s role in the management of documents under their responsibility. A brief summary of these comments is provided below:

• The committee needs to develop an approval process for each document under the responsibility of the JTCoP.

• Procedures need to be in place as to how negative votes are addressed. • Procedures need to be in place as to how comments are addressed. • The frequency of review for each guide document needs to be established. • The method to provide updates to each guide document needs to be established. • The process to edit the documents needs to be defined. • The procedures to issue ballots, compile ballot responses and address ballot

responses need to be established. • The JTCoP may want to consider the development of subgroups within the

committee to maintain particular portions of each guide. • The development of standard operating procedures will help in providing a

smooth transition as members within the committee change. Action Item: Judy Corley-Lay (NC) will lead an effort to identify existing procedures in place to maintain AASHTO guide documents and will report back to the JTCoP with her findings.

Process to Ballot the Interim Mechanistic-Empirical Pavement Design Guide Manual of Practice The members of the committee at the meeting agreed to follow the process presented below to ballot the proposed Interim Mechanistic-Empirical Pavement Design Guide Manual of Practice through AASHTO.

Step 1 – Pete Stephanos (FHWA) will provide a list of desired changes to be made to the NCHRP 1-40B ME-PDG User Manual. This list will be provided to Ed Harrigan (TRB) by the end of April.

Step 2 – Dan Dawood (PA) will work with Linda Pierce (WA) and Pete Stephanos (FHWA) to prepare a cover letter and package to go to both the AASHTO Subcommittee on Materials (SOM) and the AASHTO Subcommittee on Design (SOD) for their concurrent ballot to approve the document. A draft of the package should be provided to the JTCoP for review by April, 27, 2007. A final version of the package will be provided to Jack Springer (FHWA) to ballot through SOM and SOD after it is reviewed and edited by the JTCoP.

Step 3 – Linda Pierce (WA) will distribute Lead states to JTCoP members (completed). JTCoP members are encouraged to communicate with states outside of this list to discuss the benefits of the proposed guide.

Step 4 – Jack Springer (FHWA) will post the ballot by the first of June for 45 days. Dan Dawood will make a presentation to the SOD at their annual meeting to lobby for their approval.


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Step 5 – Jack Springer (FHWA) will send the results of both the SOD and SOM ballots to Dan Dawood (PA) after the ballot closes in July.

Step 6 – Linda Pierce (WA), Dan Dawood (PA) and Pete Stephanos (FHWA) will review and organize comments received as part of the ballot process. A decision will be made at this time if a meeting will be necessary to address any negatives and comments.

Step 7 – The JTCoP will work by email, teleconference, video conference or face to face to agree on any changes needed to the document before it is forwarded to the AASHTO Standing Committee on Highways for approval.

Process to Ballot the Guide for Pavement Friction The members of the committee at the meeting agreed to follow the process presented below to ballot the proposed Guide for Pavement Friction through AASHTO.

Step 1 – Jay Bledsoe (MO) will lead a subgroup to edit the NCHRP 1-43 guide document as agreed in the meeting.

Step 2 – Jay Bledsoe (MO) will prepare a draft cover letter for the ballot by early June, 2007. This draft will be sent to the JTCoP for review and comment. A final cover letter and revised guide document will be sent to Keith Platte (AASHTO) to ballot through SOD for approval and to Jack Springer (FHWA) to send to the SOM Technical Section 5a for review and comment.

Step 3 – The results of both the SOD ballot and the SOM review will be sent to Dan Dawood (PA). Dan Dawood (PA) will work with Linda Pierce (WA) and Pete Stephanos (FHWA) to review and organize the response. A decision will be made at this time if a meeting will be necessary to address any negatives and comments.

Step 4 – The JTCoP will work by email, teleconference, video conference or face to face to agree on any changes needed to the document before it is forwarded to the AASHTO Standing Committee on Highways for approval.

JTCoP Membership Dan Dawood (PA) led a discussion on the existing membership of the JTCoP. Currently the committee includes the following representation: Members Region 1 (NE) – 4 members Region 2 (SE) – 7 members with two vacancies (previously held by KY and VA) Region 3 (CN) – 4 members Region 4 (W) – 6 members Liaisons AASHTO Standing Committee on Aviation Standing Committee on Planning - vacant Subcommittee on Construction - vacant Subcommittee on Maintenance - vacant FHWA - vacant


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Port Authority of New York/New Jersey - vacant TRB The following includes a summary of the discussion from the committee meeting:

• The current membership includes three members from the AASHTO Subcommittee on Materials (SOM). Keith Platte (AASHTO) will investigate the minimum number of SOM members agreed to be included on the JTCoP.

• CT is currently filling one of the membership slots to represent Region 1. Colleen Kissane is no longer in a pavement position in CT. Keith Platte (AASHTO) will contact the AASHTO Subcommittee on Design (SOD) to confirm Ed Block as the replacement for Colleen Kissane to represent CT .

• The liaison representatives from other AASHTO committees have not been active on the JTCoP. Keith Platte (AASHTO) will verify the desire of each of these committees to provide liaison representation to the JTCoP.

• Dan Dawood (PA) would prefer to fill the two vacancies representing Region 2 as new members representing Regions 1 and 3 to provide a more equal distribution of members across the country. Keith Platte (AASHTO) will identify if these vacancies should be recommended from the SOM or the SOD or a combination of both.

Action Item: Keith Platte (AASHTO) will research the membership needs of the JTCoP and suggest changes as described above to Dan Dawood (PA).

JTCoP Research Needs and Strategic Plan Dan Dawood (PA) discussed the need to develop a list of research needs to support the objectives of the JTCoP. Amir Hanna (TRB) recommended that the JTCoP work with NCHRP to hold a strategic planning session to identify short, mid and long term research needs using a facilitation group at Virginia Tech University. The JTCoP agreed that this would be a productive effort and recommended that a committee of 2 members of the JTCoP from each Region be created to develop this list of research needs. Amir Hanna (TRB) noted that NCHRP will fund travel for the meeting.

The following JTCoP members volunteered to be considered as members of this planning committee:

Ed Block – CT Mike Murphy - TX Richard Zamora - CO Bill Farnbach - CA Judy Corley-Lay – NC Phil McConnell – AK Jay Bledsoe – MO Andy Gisi – KS Action Item: Dan Dawood (PA) and Linda Pierce (WA) will select the members of the committee.


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It is anticipated that the planning session will be held in the summer of 2007.

It was also discussed that the JTCoP will need to conduct efforts to plan for the next release of the ME-PDG, especially considering that the proposed guide will be balloted as an “Interim” guide. It was agreed that this planning effort should be conducted after the completion of the strategic planning effort described above and no earlier than 2008.

NCHRP Update Amir Hanna (TRB) presented an overview of the projects approved by AASHTO to be included in the FY2008 NCHRP program. The following projects were highlighted as projects of interest to the JTCoP.

• Project 1-46: Development of AASHTO Pavement Handbook • Project 10-75: Evaluation of Pavement type Selection Processes • Project 10-76: Quieter Pavements versus Noise Mitigation Measures: Initial Costs

and Benefits • Project 9-46: Mix Design and Evaluation Procedure for High Reclaimed Asphalt

Pavement Content in Hot Mix Asphalt • Project 9-47: Evaluation of the Environmental and Engineering Properties of

Warm Asphalt Technologies • Project 4-35: Enhanced Test Method for Specific Gravity and Absorption of

Coarse and Fine Aggregates A summary of the project selection and delivery process was presented and JTCoP members were encouraged to be involved on project panels. The presentation provided is included as Attachment 4 to these minutes.

Amir Hanna (TRB) noted that the JTCoP has an opportunity currently to suggest NCHRP 20-7 projects through AASHTO.

AASHTO Pavement Deflection Data Exchange: Technical Data Guide Keith Platte (AASHTO) noted that the AASHTO publication for the Pavement Deflection Data Exchange: Technical Data Guide is maintained by the AASHTO Subcommittee on Information Systems. It was agreed that the JTCoP does not need to ballot any changes to this guide as it does not come under SOD. It was suggested that the changes recommended by FHWA (which were reviewed by the JTCoP and the SOM Technical Section 5a) be provided to the AASHTO Subcommittee on Information Systems for their consideration. FHWA will complete edits to the existing document based on this understanding and will forward the recommended changes directly to the AASHTO Subcommittee on Information Systems for their consideration.

Next Meeting The committee members present at the meeting agree to meet again in the September/October, 2007 time frame. Several members volunteered to host meetings in their states. The following is a listing of cities suggested for future meetings:

• Ashville, NC • Austin, TX


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• Jackson Hole, WY • Kansas City, KS • Mystic, CT • Seattle, WA

It was agreed that the next meeting would be held in Seattle, WA.

Action Item: Linda Pierce (WA) will work with Pete Stephanos (FHWA) to arrange the details for the next meeting.

Action Item: Pete Stephanos (FHWA) will send out a calendar for potential dates for the next meeting.

Attachment 1

Meeting Attendees

Present NAME ADDRESS EMAIL/PHONE 4/12 4/13

P.O. Box 270 [email protected] James Bledsoe Jefferson City, MO 65102 (573) 751-3634

X X

280 West Street [email protected] Edgardo Block Rocky Hill, CT 0607 (860) 258-0303 X X

1593 Mail Service Center [email protected] Judith Corley-Lay Raleigh, NC 27611 919-250-4094 X X

400 7th Street SW, Room 3118

[email protected] Gary

Crawford Washington, DC 20590 202-366-1286 X 400 7th Street SW, Room 3118

John.d’[email protected] John

D’Angelo Washington, DC 20590 202-366-0121 X PennDOT, 6th floor, CKB [email protected]

Dan Dawood 400 N. Street, Harrisburg, PA 17120

717-787-4246 X

Oklahoma DOT, 200 N.E. 21st Street

[email protected] Jeff Dean

Oklahoma City, OK 73105 405-522-0988 X X 5900 Folsom Blvd., MS#5 [email protected] Bill Farnbach Sacramento, CA 95819 916-227-5845 X X 2300 Van Buren [email protected] Andy Gisi Topeka, KS 66611 785-291-3856 X X TRB/NCHRP, 500 5th St NW

[email protected] Amir Hanna

Washington DC 20001 202-334-1892 X X 500 5th St NW [email protected]

Ed Harrigan Washington DC 20001 202-334-3232 X X P.O. Box 1708 [email protected] Rick Harvey Cheyenne, WY 82003 (307) 777-4476 X X Central Lab, PO Box 191 [email protected] Andy

Johnson Columbia, SC 29202-0191 803-737-6683 X X P.O. Box 94245 [email protected] Jeff Lambert Baton Rouge, LA 70804 (225) 379-1937 X X 1409 Coliseum Boulevard [email protected] Larry Lockett Montgomery, AL 36110 (334) 206-2201 X X PO Box 2261 phil.mcconnell@arkansashighway

s.com Phil McConnell Little Rock, AR 72203 501-569-2301 X X


1980 West Broad Street [email protected] Aric Morse Columbus, OH 43223-

0899 614-995-5994 X X Texas DOT, 4203 Bullcreek #37

[email protected] Mike Murphy

Austin, TX 78731 512-465-3686 X X 6300 Georgetown Pike, HRDI-04

[email protected] Katherine

Petros McLean, VA 22101-2296 202-493-3154 X WSDOT, PO Box 47365 [email protected] Linda Pierce Olympia, WA 98504-7365 360-709-5470 X X 444 N. Capitol St. NW, Suite 249

[email protected] Keith Platte

Washington DC 20001 202-624-7830 X X VAOT, Nat’l Life Bldg, Drawer 33

[email protected] Michael

Pologruto Montpelier, VT 05633 802-828-2793 X 6300 Georgetown Pike, HRDI-04

[email protected] Jack Springer

McLean, VA 22101-2296 202-493-3144 X X 400 7th Street SW, Room 3118

[email protected] Peter

Stephanos Washington, DC 20590 410-321-3100 X X 1400 Gervais Avenue [email protected] Curt Turgeon Maplewood, Mn 55109 (651) 366-5535 X X 1220 Washington Avenue, POD 34

[email protected] Julian

Bendana Albany, NY 12232 518-457-4663 X X 1019 Erie Ave [email protected] Richard

Zamora Pueblo, CO 81001 719-546-5778 X X 400 7th Street SW, Room 3211

[email protected] Nastaran

Saadatmand Washington, DC 20590 202-366-1337 X X Dave

Newcomb NAPA 5700 Forbes Blvd Lanham, MD 20706

[email protected] 301-731-4748 X

Tony Bianchi AASHTO [email protected] 202-624-5821 X X

Laura Fenley Wisconsin DOT 3502 Kinsman Blvd Madison, WI 53704

[email protected] (608) 246-5455

X

Bob Meyers New Mexico DOT 1120 Cerrillos Road Santa Fe, NM 87504

Robert. [email protected] (505) 827-5466

X

Bill Barstis Mississippi DOT P.O. Box 1850 Research

[email protected] (601) 359-7649 X


Division Jackson, MS

Matt Witczak Dept. of CEE ASU, Phoenix, AZ

[email protected] (480) 585-2197 X

Michael Ayers

ACPA 15262 N. 450 E Fithian, IL 61844


X

Claudio Zapata

ASU Dept of CEE P.O. Box 875306 Tempe, AZ 85287-5306


X

Gregg Larson ARA 100 Trade Center Champaign, IL 61820


X

Mike Darter ARA 100 Trade Center Champaign, IL 61820


X

Harold L. Von Quintis

ARA 102 Northwest Drive, Suite C Round Rock, TX 78664


X

Chris Wagner

FHWA 61 Forsyth Street, SW Suite 17T26 Atlanta, GA 30303


X

Attachment 2

ME-PDG User Guide

Comments/Recommended Changes

AASHTO Joint Technical Committee on Pavements April 19, 2007 Review of Ballot Comments – ME-PDG Users Manual

The following are comments received from the AASHTO JTCP on the approval of the ME-PDG User Manual to be sent to the AASHTO Subcommittees on Design and Materials. The ballot passed with 81% of the ballots approving the guide, however several comments were raised during the ballot. The following is a summary of these ballots and action to be taken by the JTCP to address the comments. Each comment has been categorized as: Editorial, Change, Comment, Question, Addition, Implementation. Name Category Comment Review Action A. Mergenmeier (VA)

Addition In page 106 (2nd paragraph of section 11.5), it is stated the resilient modulus value estimated from DCP could directly be used without any adjustment. CBR could be estimated from DCP data which could be converted into resilient modulus with some conversion factor. Since various agencies use their own different factor, is it implied that the agency could use their own factor to estimate the resilient modulus from CBR and then use it directly in the software? Also, the software appears to be able to calculate resilient modulus value from CBR values and soil classification. A clarification on this may be helpful

Harold V. stated that relationships are listed for different correlations or user can input Mr value directly using their own correlations outside of the software for added flexibility.

Modify document to include a statement that other methods are available. Text should clarify that the input should be the lab Mr.

A. Mergenmeier (VA)

Editorial At the end of each chapter, suggest the next chapter start on the next page to separate the chapters

Make editorial change

E. Block (CT)

Addition Perhaps it is the intention of the document to encourage the pavement designer to seek to comprehend all the concepts contained in the Guide as he or she goes through a design; the Interim User Manual is successful in doing this; the downside, in my view, is that the actual process of executing a design is somewhat diluted among the discussion; this is not, however, a critical deficiency, but rather an encouragement to perhaps

A flowchart is included in the draft calibration guide that is a good example.

Add a flowchart to the document to outline the steps required to complete an analysis and reference sections within the document.


Name Category Comment Review Action include a one-page suggested step-by-step diagram that includes a reference to the particular section in the Manual. I believe this would be of great value to pavement designers, especially those who have not yet used the software

M. Murphy (TX)

Addition The Guide document is comprehensive and provides good information regarding mechanistic pavement design concepts. However, although the Guide provides general information about hierarchical inputs, additional information is needed in the Guide about how to actually use the MEPDG software.

Will not include any software information in the User Manual.

Include in version 2.0 of the software.

M. Murphy (TX)

Addition The Guide is referred to as a 'design guide' but the MEPDG is actually an analysis program, not a design program. The program accepts inputs from the user for all variables associated with thickness, material, traffic climate etc. and then predicts performance. Perhaps further work result in a Guide that can determine required pavement layer thicknesses based on traffic, climate, materials and other factors. The analytical (rather than design) aspect of the Guide can be used to evaluate pavement structures during forensic investigations.

Some of these concerns were addressed by software demo and the ability to change some of the intermediate files. Concern of analysis versus design will be addressed by Darwin task force.

Pass on to Darwin Task Force for version 2.0

M. Murphy (TX)

Addition It would be helpful if the Guide included a diagram showing how the different modules are connected and how information flows from module to module. It would be beneficial for the MEPDG software to include a feature that shows these relationships.

Provide information on the internet – through DGIT for now. Need to provide guidance in the software, when possible, to illustrate inter-relationships of variables, although it is not feasible to include al of the warning remarks. Could be addressed through hyperlinks showing a flowchart.

Add a one paragraph warning in the document to let user’s know that they need to understand the inter-relationships of variables. Harold Von Quintus will add a flowchart with references to sections.


Name Category Comment Review Action Need a wiring diagram for Ver. 2.0

DGIT will draft a list of counter-intuitive inputs and Mike Murphy will be liaison to post these counter-intuitive inputs on Lead States or FHWA website.

M. Murphy (TX)

Addition The Guide does not address surface treated pavements which constitute approximately 44% of Texas' state system.

Judith Corley-Lay will be liaison to look at this issue and work with Texas and Virginia. Surface treatments were not considered during the development of the MEDPG since they are not structural. Consider as a need for the next version of the guide.

M. Murphy (TX)

Addition The Guide provides only a short discussion regarding how reliability in incorporated in the design. More information is needed regarding how the recommended reliability values in Table 62 are applied.

TX withdrew comment based on presentations. Also mentioned that DGIT will be developing a technical brief on reliability that will be posted on the Lead State and FHWA website.

M. Murphy (TX)

Addition The Guide discusses approximately 100 inputs that are required to run the MEPDG software. However, based on 3 sensitivity analyses performed by TxDOT it appears that there are a number of inputs that show no sensitivity. More explanation is needed regarding the importance of each variable.

The need for a synthesis study of sensitivity analyses completed was discussed.

This will be addressed by the flow chart that will be added by Harold Von Quintus in the next version.

R. Harvey (WY)

Addition Page 4, Section 3.3 - Several pavement strategies included in section 3.3 and 3.4 were not calibrated, probably due to the lack of test sections. Some of these strategies are now becoming highly used: semi-rigid pavements, in-place pulverization of flexible pavements, break and seat of JPCP. A single state may not have enough of these sections to perform

Suggested that as states develop new models of recycled aggregate or other materials these models should be provided to AASHTO for possible inclusion in future version of the software.

Text will be added to provide caution to the user by stating that models were not nationally calibrated and would need to be addressed through local calibration.


Name Category Comment Review Action calibrations with their data. Should the JTCP consider this task on a national or regional basis? Not including new strategies may encourage the continued use of existing design methods

R. Harvey (WY)

Addition Page 57, Section 7.1 - Design/Analysis Life. Stage construction or placing some of the pavement at a latter date is not addressed. Was this concept outside the scope of the project? It seems the program should be able to analysis a paving section where 6” of an 8” HMA section is placed at the time of reconstruction and 2” is planned to be placed 10 years latter. The analysis may show that this strategy is not advisable, but it would be useful to be able to analysis the effect of additional surfacing placed at a latter date.

Currently outside the scope of the project however you can trick the program to predict the damage from the first and second stage of construction through two step process.

Provide a short explanation on the DGIT website on how the software can be used to simulate staged construction

R. Harvey (WY)

Addition Page 60, Table 4 - Seems like a rehabilitation strategy could be applied in conjunction with a threshold value for some of the distresses listed. For example, if you exceeded a transitional transverse crack distress threshold at year 15, but could apply a second stage rehabilitation and restore the surface, then your design would actually meet the criteria

Addressed through comment listed above

R. Harvey (WY)

Addition Page 138, Section 13.2.8 - More information is needed on resilient modulus inputs particularly for laboratory tested material. Should results from in-situ samples with possibly high moisture contents due to spring thaw be compared to reconstituted samples at optimum

Stated that level 1 soils for PCC can’t be used because analysis is stress dependant.

Edit 2nd paragraph under Resilient Modulus on Page 112 to add reference to FHWA recommendations and add note that all inputs should be based on optimum moisture content..


Name Category Comment Review Action moisture content? Should a reconstituted sample at optimum moisture be entered in a summer month even if it was collected in the spring so that the ICM can apply the appropriate changes due to moisture and frost? Is it better to provide the three k-values or should one determine a single value for resilient modulus? How does one calculate the stresses within the structure to select the appropriate resilient modulus value from the array of values collected during testing? Is there a suggested method for performing a non-linear regression to determine k-values?

R. Harvey (WY)

Addition Page 170, Section 15 - Tips on installing climate data should be included such as: it needs to be downloaded in order to use the integrated climate model, how to do it, and which folder the files should be downloaded to. Also, it should be mentioned that the nearest weather station may be in an adjacent state, so they need to be downloaded as well.

Discussed need for brief write-ups to provide tips on use of the version 1.0 software.

Gregg Larson will develop a special topic paper for creating climatic files and post on Lead States and FHWA website. Chris Wagner will work with Gregg to help develop these special topic papers. These special topic papers will be separate from the document.

R. Zamora (CO)

Addition Page 25, Section 5.2.1 Should include a more detailed discussion on how the layering works and how many layers can be analyzed.

Reference will be added for detailed information on page 113.

R. Zamora (CO)

Addition Page 69, Climate. We have looked at the available weather stations in our state and are concerned with the very limited number available that have hourly information. This is especially concerning given the fact that the location of the stations relative to some of our interstate pavements does not even come close to approximating the climatic conditions at

Will be addresses by special topic paper that Gregg Larson will develop (see above).


Name Category Comment Review Action the site. For example, we have extreme environments through the mountainous portions of our state, but there are no weather stations in close proximity. More guidance should be provided on how to manually create additional stations.

A. Mergenmeier, (VA)

Change The negative vote is due to the name of the document. Virginia DOT review of the document concluded that it is not a user manual. Two options that would result in Virginia DOT withdrawing the negative are:

1. Change the name of the document to something similar to: AASHTO Interim Guide for Mechanistic-Empirical Design of Pavement Structures 2

2. Add example pavement design analysis with software screen shots. It is very important to include examples of input/output from real projects for the most common designs. This way the designer can run through the examples and gain confidence about the Guide and software.

Software manual will be developed as part of the AASHTOWare release of version 2.0

Members voted unanimously to change title to “AASHTO Interim Mechanistic-Empirical Pavement Design Guide Manual of Practice”.


Change The majority of the data and equations in Chapter 5 would be more appropriate as an appendix to a pavement design guide than in the guide itself.

Found not persuasive


Change The effect (or benefit) of using geotextile is not predicted by ME design. However, the software has a check box “Geotextile present on existing surface” in the input screen for Structure. The reader may wonder if this check box has significance

1-40 Panel recommended the removal of all references to geotextiles. JTCoP agreed with panel and also wanted the button removed from the software screen as well. Texas A&M is conducting research on this.

ARA agreed to remove button from software for geotextiles and would release an updated version of the software, version 1.100. Harold Von Quintus would remove all references to geotextiles on document


Name Category Comment Review Action on the design at present or it is there to incorporate any future enhancement

E. Block (CT)

Editorial Page 131 - 2nd paragraph it can be read that the pre-overlay treatments are inadequate instead of the existing pavement;

Considered editorial and will be addressed in updated document.

E. Block (CT)

Change Page 167 - Sec. 14.5, "Judging the Acceptability..." 2nd paragraph, it is not inevitable that altering a design feature to compensate for one distress will result in an increase of another distress.

Add example to document of related example (i.e. Superpave efforts to reduce rutting can increase cracking).

L. Pierce (WA)

Change All "should" and "must" statements need to be revised to "could" or "may" or other appropriate verbiage. This is a "guide" not a document that directs.

L. Pierce will identify recommended changes

Changes will be made to the document based on recommendations from L. Pierce.

L. Pierce (WA)

Change Reference to the use of geotextiles to reduce the thickness of the HMA must be removed. There is no empirical basis for this reduction and until a mechanistic process is developed, these statements should not be incorporated into the Guide.

Already addressed. Members agreed to remove all references to geotextiles.

L. Pierce (WA)

Change Page 114, last paragraph - I don't believe we should be promoting the use of geogrids for strengthen pavement layers when we currently do not have a mechanistic basis for this claim.

Members agreed to remove all references to geogrids. The beginning general statement should remain in document.

Remove reference to any benefit for the use of the geogrid.

L. Pierce (WA)

Change The reference to smoothness as a design parameter needs further discussion. Though smoothness is an important feature, it is not a design feature - stating that it is only a prediction of resulting distress must be made more clear early on in the document. As it reads today, it is implied that smoothness is a design feature and not an output.

Harold will reword discussion on smoothness to address this concern.

L. Pierce Change Page 17 - under geogrid bullet "These Will handle as discussed above.


Name Category Comment Review Action (WA) materials are used to strengthen layers...at

this time" should be changed to "These materials cannot be simulated in the MEPDG at this time."

L. Pierce (WA)

Change Page 17 - reference to the ability of the guide to design JRCP should be removed.

Remove paragraph – add comment that the design only includes JPCP and CRCP.

Harold will remove discussion on how to trick software to design JRCP.

L. Pierce (WA)

Change Table 1 - the assumption that 2" of HMA is equivalent to a fabric must be removed.

Members agreed to remove all references to use of fabrics as discussed earlier.

L. Pierce (WA)

Change Paragraph 10.1 - use of GPR testing may be considered, not must be considered.

Will be included in full list developed by L. Pierce.

L. Pierce (WA)

Change Paragraph 10.3.3 - all loss of support does not imply the presence of a void!

Change title to “Loss of Support” – discuss that it is not always a void

Void will be changed to loss of support. Caution will be added on use of GPR

R. Harvey (WY)

Change Are better descriptions of the distress indicators needed to understand/develop the failure criteria. , Section 4.5 - Some of the indicators are given as areas, but do not include the assumptions like whether in one wheel-path or both, the width, full width, etc. For transverse cracks, unclear on whether these cover the width of the lane, the width of the crack, etc.

HMA definitions based on LTPP definitions that don’t include severity. States need to understand that they can use their own collection protocol provided they understand that the calibrations will be different.

Need to provide detail to quantify distress on Page 22. Need to verify the units and thresholds in Table 17 and 18 on Page 90 and 91. Need to verify the threshold levels. Include reference to Calibration Guide in overview.

R. Harvey (WY)

Change Page 33, Eq. 11.a - needs units defined and an explanation of how delta K is obtained. What defines a cooling cycle?

Will not address at this time.

R. Harvey (WY)

Change Page 88, Section 10.2.8 - The AASHTO procedure for ignition extraction recommends the use of a correction factor. How is that to be addressed when existing pavements are being analyzed and a correction factor is not readily available? Suggestion: Use prior test results if possible and use chemical

Will not address at this time.


Name Category Comment Review Action extraction when the known or anticipated correction factors are greater than 0.5 or the correction factor is unknown.

R. Harvey (WY)

Change Page 88, Section 10.2.8 - The Dynamic Modulus section states that laboratory testing should not be performed on intact samples because erroneous results may occur due to age hardening. The next section states that IDT should be performed to determine dynamic modulus of moisture damaged samples. These statements are contradictory. How should one determine dynamic modulus if the material is both age hardened and moisture damaged? Also, which procedure(s) should be utilized to determine IDT strength? If FWD back-calculation is used, how does one obtain unique values when considering multiple HMA lifts?

Note that all of the existing pavement for asphalt pavement (multiple lifts) are treated as one layer.

Reword paragraph to avoid confusion.

R. Harvey (WY)

Change Page 91, Section 10.3.2 - The manual states that GPR is preferred to obtaining cores for determining layer thickness. It seems that the guide is promoting the use of GPR instead of just indicating that it is an option. GPR is a useful tool in many applications, but coring or boring may still be needed for some investigations.

Recommend change in text to suggest other alternatives to use of GPR and not require use of GPR. Suggest GPR Primer as a need outside of this document.

Add comment that GPR is one of many methods to determine layer thickness.

R. Zamora (CO)

Change Page 17, Staged Construction Events – I would suggest this section be re-written to recommend analysis to evaluate initial construction over anticipated time before final section is completed. Also evaluate final section over remaining design life. This process is alluded to later in the document.

See response above.


Name Category Comment Review Action R. Zamora (CO)

Change Page 18 – Interface friction. No mention of PCCP assumptions. Am guessing the model assumes full friction for PCCP over HMA. If correct, should we state that?

Make sure that there is some guidance for how to incorporate interface friction.

Harold will add information for HMA and PCC interface friction assumptions

C. Turgeon (MN)

Comment Not sure if I'm voting on just the quality and accuracy of this manual; or of the quality and accuracy of the Design Guide product Normally, a great deal of time is provided for review of such items prior to voting. Several people within the DOT should have opportunities to review and provide comments. Due to the time frame and vacations, this has not taken place.

C. Turgeon (MN)

Comment Regarding the guide: Figures 12 and 14 are troubling. A great deal of the data is on the y-axis. The Guide is predicting something will happen, yet in reality, nothing actually happened. A very high r-squared is reported for both cases when in fact the results from this part of the guide are unusable.

C. Turgeon (MN)

Comment The lack of quality of the JPCP slab cracking models should probably make my vote a Non-concur on the design guide; but since the manual accurately represents this weakness: the manual is essentially correct.

E. Block (CT)

Comment Although the time for the review of this document per se is limited, the Interim User Guide does appear to enable a pavement designer with experience to execute a trial pavement design (new construction or rehabilitation).

J. Bledsoe (MO)

Comment In general I think the manual is very good. I think it provides a very good


Name Category Comment Review Action background on how the guide was developed as well as how to use it.

J. Corley-Lay (NC)

Comment I am not certain that this is actually a users manual. It does not tell a user how to use the MEPDG. It does serve a valuable overview purpose.

M. Murphy (TX)

Comment The Guide discusses some data inputs that will only be known during construction or even after construction. For example, although the material type is known in advance of project letting, the material source is not know. Also, mix design properties may vary during construction as the contractor implements revised Job Mix Formulas (JMFs) to ensure that the mix meets specification requirements.

M. Murphy (TX)

Comment TxDOT supports balloting the Guide and software as provisional. The Guide has a number of strengths which should be further developed and refined through cooperative efforts by the State DOTs.

M. Murphy (TX)

Comment In it's present form, the Guide and software will likely be used by TxDOT for high type pavements.


Editorial The sub-header of the document under NCHRP Project Number (“Local Calibration Guideline for the Recommended Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures”) does not reflect the content of the document. It is stated at several locations of the document (page 1, 25) that local calibrations are not part of the document. This sub-header should be deleted



Name Category Comment Review Action A. Mergenmeier, (VA)

Editorial In one of documents VDOT receives, pages 47-56 had been repeated after page 56



Editorial The color contrast used in figures 3 and 4.a made some of the text in the figures difficult to read. The color contrasts in these figures need to be adjusted for better legibility.



Editorial Figures 32 and 33 in page 164 appear more of tables instead of figure. These may need to be changed to Tables


C. Turgeon (MN)

Editorial Search the word "TRAIL" in the text. It appears several times, but should be the word "TRIAL" as in trial mix of HMA. Spell check won't pick that out for you.


E. Block (CT)

Editorial Typographical errors (Table 29) "Remover and Replace" instead of "Remove and Replace" and subsequently "Remove and Replaced."


E. Block (CT)

Editorial This is by no means a complete list of editorial comments (I have not edited the entire book, but in my opinion a strictly editorial revision is necessary -- I will grant that given the sheer volume of information contained in the User Manual, these errors are rather minor.) Overall I concur.


J. Corley-Lay (NC)

Editorial The Users Manual needs a thorough editing... spell check is only effective if the incorrect spelling is not a word.


L. Lockett (AL)

Editorial In Sections 2.1, 2.2 and 2.3, some pertinent AASHTO standards are omitted, e.g., T 319; some of the standards do not have the correct or at least the full title shown, e.g.,TP 62; and some ASTM standards are shown for which there are

Larry Lockett will send changes on AASHTO test methods next week to Pete Stephanos for incorporation into the interim MEPDG.


Name Category Comment Review Action AASHTO counterparts, but the AASHTO standards are not referenced, e.g., ASTM D3282 has an AASHTO equivalent, AASHTO M 145.

L. Pierce (WA)

Editorial When applicable AASHTO test methods should be referenced rather than ASTM.


L. Pierce (WA)

Editorial In several places the figure or table preceeds the text discussion, this should be changed so that the text occurs first.


L. Pierce (WA)

Editorial Figures similar to Figure 3 and 4 should be developed for PCC. At a minimum, comparable tables and figures for both HMA and PCC should be developed.

Page 58 provided good guidance on HMA inputs. Harold will add similar figures for PCC.

L. Pierce (WA)

Editorial For consistency, the border around the Figure 8, 9 and 24 should be removed.


L. Pierce (WA)

Editorial Missing pages 59 and 60 in printed document.


R. Harvey (WY)

Editorial Page 1, Section 1.1 - It is stated that "this manual does not provide guidance on developing regional or local calibration factors for predicting pavement distress and smoothness"; however, the title "Local Calibration Guidance for the Recommended Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures" on the front cover may lead one to believe otherwise.


R. Harvey (WY)

Editorial Page 4, Section 1.2 - The word "insure" should be changed to "ensure".


R. Harvey (WY)

Editorial Page 30, Section 5.2.3 - No equation number assigned to what is assumed to be Equation 5, which contains variables that are not defined. What are DI and Nf? For Equation 6.a and 8, it is not specified how DIbottom and DItop differ from DI? What



Name Category Comment Review Action are they?

R. Harvey (WY)

Editorial Page 34, Eq. 11.e - Equation 11.e needs units defined for HHMA.


R. Harvey (WY)

Editorial Page 43, Section 5.3.2 - Equations 20.a,b,c,d don’t have units for all of the variables


R. Harvey (WY)

Editorial Page 43, Section 5.3.2 - Equation 24.d needs units established for deflections at slab corners


R. Harvey (WY)

Editorial Page 50, Eq. 29 - Need units for Jc, Pb Make editorial change

R. Harvey (WY)

Editorial Page 51, Eq. 30 - Units are not established for �i,j.


R. Harvey (WY)

Editorial Page 87, Section 10.2.7 - 4th paragraph, change “maybe” to “may be”


R. Harvey (WY)

Editorial Page 100, Table 21 - There are no units specified for indirect tensile strength


R. Harvey (WY)

Editorial Page 115, Fig. 23 - 1st box, middle column, remove the word “is”


R. Zamora (CO)

Editorial Page 3, Figure 2. Would be good to include a similar figure for PCCP so users can understand the changes


R. Zamora (CO)

Editorial Page 15, Section 3.4. I assume the guide will also be able to analyze JPCP both with tied and untied longitudinal joints. Should we include a sentence that states that in this section?


R. Zamora (CO)

Editorial Page 52, Figure 18 – This figure looks like it’s misplaced and should be moved up so it is not mingled directly in the JPCP smoothness section.


JTCoP Editorial Raised during the meeting. Update Table 10 to include missing data.

M. Murphy

Implementation

The Guide and MEPDG software are significantly more complex that pavement

To be considered by JTCoP in future strategic planning sessions.


Name Category Comment Review Action (TX) design software and manuals currently in

use by TxDOT. We estimate that at least 1 week of class room training will be required to train a knowledgable pavement designer. This compares to about 2-1/2 days training for TxDOT pavement design software and the MODULUS backcalculation program.

J. Bledsoe (MO)

Question I have a question about one subject that seems contradictory. There is a reference on page 16 stating that the MEPDG does not have the capability to predict volume change from frost susceptible soils or expansive clays. However, it is stated that a "key step" is and evaluation of shrink swell potential of highly plastic and potential weakening of frost susceptible soils. ?

It is assumed that frost susceptible soils will be addressed through treatment before design is conducted. Frost does have an effect on ride (heave) and change in material properties (climatic model)

Add text to explain limitations of design process to predict impacts of frost heave.

R. Harvey (WY)

Question Are construction related longitudinal cracks to be included? Question whether cracking caused by joints and paver operation should be included in analysis of the paving sections.

System does not identify the specific types of cracks – need to address in follow up work to current guide.

R. Harvey (WY)

Question Page 32, Section 5.2.3 - Is the analysis sensitive to the damage and distress transfer functions? A user may assume that since they were not calibrated, it is a critical flaw of the system.

Un-calibrated models – use with caution. Need to include in list if of future needs.

R. Harvey (WY)

Question Page 82, Table 14 - Is there a recommended procedure for using FWD to determine joint LTE?

Only in general - include in state developed procedures/policies that will likely be developed during implementation.

R. Harvey (WY)

Question Page 88, Section 10.2.8 - Why use the PCC Static Modulus factor of 0.8? Where does this factor come from?

Conversion to lab values

R. Harvey Question Page 88, Section 10.2.8 - The guide Back calculation has not been included.


Name Category Comment Review Action (WY) recommends back-calculating values for

concrete sections. Is there really a "standard" for evaluating the FWD information, it still seems sensitive to equipment, season, moisture, etc. What about provisions for calibrating the FWD?

How do we do this in the future – states will handle back-calculation in the future. 1-37 panel was instructed to allow the flexibility to have states conduct their own back-calculated properties.

R. Zamora (CO)

Question Will calibration guide give info on model sensitivity for the various inputs so agencies can focus limited resources on sensitive inputs?

Need to develop synthesis of sensitivity analyses.

Attachment 3

Guide on Pavement Friction

Comments/Recommended Changes

AASHTO JTCoP Comments on NCHRP 1-43 “Guide for Pavement Friction”

Page 1 of 4

AASHTO Joint Technical Committee on Pavements (JTCoP) Comments on NCHRP Project 1-43 report “Guide for Pavement Friction”

Background: The JTCoP needs to accept the Guide and recommend it to the Subcommittee on Design (SOD) to be adopted by AASHTO. Mike Murphy (TX) volunteered to work on getting the comments together on the guide (contingent on if Mr. Jay Bledsoe is not available). At the December 2006 meeting of the JTCoP, Mike Pologruto (VT) motioned to ballot the “Guide for Pavement Friction”; Andy Mergenmeier (VA) seconded the motion. No opposition, motion passed. Therefore, the JTCoP we will be balloting the guide during the meeting in Irvine, CA on April 12-13, 2007. The table below provides a summary of the comments received from JTCoP members and the recommended actions.

Comment Submitted by Review of feedback Recommended Action

1 I reviewed the document... in less detail than Virginia did... but am in favor of moving the new guide to Friction forward. Given that the current guide is from 1976, it is time for an update.

Judy Corley-Lay (NC)

OK Recommend to SOD for adoption

2 The researcher has in many cases referred to ASTM standards when there are equivalent AASHTO standards, specifically, ASTM E 274, E 501, and E 524 on page 14 of the Guide and elsewhere. The AASHTO equivalents (all are category “B” standards), T 242, M 261 and M 286 are not mentioned anywhere that I can find in either the Guide or the Final Report. To give credit the researcher did list both ASTM and AASHTO standards for other tests later in the Report and Guide. Since the research was funded by the AASHTO states, I would suggest that this oversight be corrected prior to any balloting by the JTCoP.

Larry Locket (AL) Primarily editorial L. Lockett will send recommendations to FHWA

3 Also, the parts of the Guide of primary interest to materials engineers –at least this one--, Section 4.3.2, Selecting Aggregates and Section 4.3.4, Development of Construction Specifications are void of any useful information.

Larry Locket (AL) Agree, not much useful info in these areas, but suggested changes are more than editorial (Substantive change) It was suggested that a needs statement be developed by the JTCoP to develop a good construction specification.

Modify document to refer to Section 4.2.1 under “Selecting Aggregates”

4 Technical review of the Guide for Pavement Friction was completed by the Virginia Department of Transportation (VDOT) and the Virginia Transportation Research Council (VTRC) personnel and found the Guide satisfactory for adoption as AASHTO document. It

Andrew Mergenmeier (VA)

Observation


Page 2 of 4

Comment Submitted by Review of feedback Recommended Action provides a valuable reference in the subject of Pavement Friction. However, the following issues/concerns are presented for consideration by AASHTO before full adoption of the Guide:

5 On Page 44, 2nd paragraph - Moh's hardness test - The US Army Corps of Engineers has a standard practice covering this test CRD-C 130-01 Standard Recommended Practice for Estimating Scratch Hardness of Coarse Aggregate Particles. The next two sentences imply a distinction between visual inspection and petrographic examination (C 295). The level of detail needed and the nature or the material under examination will lead the examiner to decide exactly what techniques are necessary to perform the examination. C 294 is designed to describe the terms that a geologist would use in reporting the findings of an examination. FHWA-HI-91-025 Rock and Mineral Identification for Engineers might serve as the document for the cursory examination.


Probably a comment that can be addressed editorially.

Modify document to include USACE test method reference. Include FHWA-HI-91-025 as reference in Table 4.

6 On Page 44, 3rd paragraph – the first two sentences contrast aggregates made with hard v. soft mineral saying those with hard minerals may polish easily while those made of moderately soft (3-6) alone resist polishing. This needs clarification. The harder minerals may polish, but will do so at a relatively slower rate, and therefore the initial surface texture is important. A rough surfaced hard rock will take some time to polish, in contrast to already smooth-textured gravel. The moderately soft rock may resist polishing if it is composed of grains of different hardness, but the sentence doesn’t convey this.


Could probably be addressed with reworking the paragraph although it might require technical background

Will not be addressed in this version of the document.

7 On Page 45, 2nd paragraph – much disagreement can be found with the statement that the LA abrasion test is commonly used with good success. The problem is that many harder, polish resistant rocks are brittle leading to high losses in the LA.


Editorial change Will not be addressed in this version of the document.

8 Some additional information could be provided about the insoluble residue test. There are some rocks composed of silicate minerals that have hardness values of 3 or less. The stone from Galax, Virginia is an example. Useful information can be obtained from examination of the insoluble material. Hard minerals in sizes 150-300 um as indicated in Table 5 can be beneficial, but also the –N0. 200 fraction composed of clay minerals can also promote differential wear that maintains frictional properties.


Point may be valid but looks like a specific situation where general recommendations in the guide do not apply. Recommend either editorial change or ignore comment.

Will not be addressed in this version of the document.


Page 3 of 4

Comment Submitted by Review of feedback Recommended Action Additional references that would be useful are: T. West and J. O’Brien, 2005. A Coarse Aggregate Paradox for Indiana Highway Pavements, Less is Better. 58th Highway Geology Symposium. J. O’Brien, 2004. Frictional Resistance of Aggregates for Hot-Mix Asphalt Pavements. MS Thesis, Purdue University, 140pp.

9 On Page 45, 5th paragraph – examples of the non-standard polish susceptibility tests could be provided.


Editorial, with some technical input Edit document to provide reference to new NCAT wearing device – FHWA to provide input.

10 On Page 46, Table 5 the following is noted: Test type for composition and structure for coarse and fine aggregate should be changed from "Petrographic Analysis" to "Petrographic examination".

Aggregate Property - in angularity, shape & texture of coarse aggregate, is conical particle shape correct? It is suggested to use pyramidal instead if that is the general shape that is intended.


Editorial

11 Maryland SHA has reviewed the guide and we would vote to approve the guide if it is balloted. It is very well written and I can certainly see this as a useful guide for state agencies. Would AASHTO publish both the guide and the final report or would the final report be included as a reference? The final report does provide some good detail that could help a designer. We have the following brief comments:

Pete Stephanos (MD)

comment AASHTO will only publish the guide – not the final report which will be available on the web through NCHRP. Revise document to include reference to the web NCHRP report

12 The guide does not include much discussion on the establishment of “friction demand categories.” There is some discussion later in the guide suggesting that the demand categories should be related to different investigatory/intervention levels as well as roadway geometry, roadway type, traffic level, etc. It might help if there were more guidance provided in how an agency would go about establishing “friction demand categories”.

Pete Stephanos (MD)

Substantive comment, would require work to enhance the guide as recommended.

13 There isn’t a great deal of definition on how an agency should quantify crash statistics. The guide references “crash rates”, “wet to dry accidents”, and “wet crashes” without defining how these values are determined. In Maryland we also look at a ratio that is an indication of

Pete Stephanos (MD)

Substantive comment, may be controversial in some States

Consider editing the document to provide general definition of the terms.


Page 4 of 4

Comment Submitted by Review of feedback Recommended Action the frequency of wet crashes on days where the pavement surface is wet vs. the same ratio when the pavement is dry. Including some discussion on crash indicators would be helpful.

14 On Page 45 "other non standard" polish susceptibility tests are referenced. Could more detail be provided here (NCAT polisher).

Pete Stephanos (MD)

See comment #9 from Virginia Possible list other possible tests under development – see related Item 9 above.

15 On Page 40 the extent of aggregate testing is discussed briefly to qualify the frictional characteristics of aggregate sources. It would be helpful if more guidance were provided on the extent/frequency of testing required to properly qualify aggregates. This is also briefly discussed under Quality Assurance.

Pete Stephanos (MD)

Substantive comment Will not be addressed in this version of the document.

16 It would be helpful if the guide included some discussion on the use of recycled materials in HMA and PCC mixes and how they can affect frictional properties of the mix.

Pete Stephanos (MD)

Substantive comment Consider for future research needs

17 Vermont AOT has reviewed the guide and we would vote to approve the guide if it is balloted.

Michael Pologruto (VT)

OK Recommend to SOD for adoption

Attachment 4

National Cooperative Highway Research Program (NCHRP)

Research for Improved Pavement Design and

Construction

National Cooperative Highway National Cooperative Highway Research Program (NCHRP) Research Program (NCHRP)

Research for Improved Pavement Research for Improved Pavement Design and ConstructionDesign and Construction

April 2007April 2007

NCHRPNCHRP-- National Cooperative National Cooperative Highway Research ProgramHighway Research Program

• An AASHTO program sponsored by state DOTs• Started in 1962• Annual funding ~ $35 million/year• Contributes to advancements in all aspects of highways• 8 fields of research (Administration, Planning, Design,

Materials and Construction, Soils and Geology, Maintenance, Traffic, and Special Projects)

• 25 Subject areas (pavements, concrete materials; bituminous materials; general materials; specifications, procedures, and practices; etc.)

NCHRP: GoalNCHRP: Goal--Oriented ResearchOriented Research• Responds to state DOT needs: DOTs and AASHTO

committees propose research topics; SCOR selects projects.

• Ensures applicability of the results: state DOTs and other sectors of the highway industry participate in monitoring the research.

• Results are published by NCHRP (reports, digests, synthesis, CD-ROMs, and Web documents) orby AASHTO (guides/manuals, specifications, and test methods), and often adopted by state DOTs and other organizations.

NCHRP FY 2008 NCHRP FY 2008 -- SummarySummary

Programmed for FY 2008:• 23 Continuation projects ($9.600 million)• 36 New projects ($16.450 million)• 5 New projects referred to existing projects (0.830 million)• 8 Contingent projects ($2.225 million)• Total 64 projects ($26.880 million) in 18 problem areas (safety,

planning, environment, hydrology/hydraulics, administration/policy, operations, security, bridges, maintenance, materials, pavements, etc.)

• 6 new projects related to pavements/pavement materials

NCHRP FY 2008 ProgramNCHRP FY 2008 Program

Submitted Programmed• Continuations 24 ($9.995) 23 ($9.600)• New Projects 122 ($45.605) 36 ($16.450)• Other New 5 ($0.830)• TOTAL 146 ($55.555) 64 ($26.880)• Contingent 8 ($2.225)

• FY 2007 (New) 188 ($74.772) 54 ($21.050)

NCHRP FY 2008 New ProjectsNCHRP FY 2008 New Projects

Submitted Programmed/Contingent

• Member Dept. 59 16• AASHTO Com. 59 24• FHWA 4 1• TOTAL 122 41

NCHRP FY 2008 Selected Projects NCHRP FY 2008 Selected Projects -- 11

• Project 1-46: Development of AASHTO Pavement Handbook

Develop a document that discusses the different aspects of pavements (design, management, rehabilitation, preservation, friction, noise, smoothness, etc.).


• Project 10-75: Evaluation of Pavement type Selection Processes

Identify and evaluate pavement type selection processes, including alternate design/bidding approaches.


• Project 10-76: Quieter Pavements versus Noise Mitigation Measures: Initial Costs and Benefits

Identify and recommend methods for evaluating the benefits of noise-mitigation approaches applicable to highway transportation.


• Project 9-46: Mix Design and Evaluation Procedure for High Reclaimed Asphalt Pavement Content in Hot Mix Asphalt

Develop a mix design method and specification for hot-mix asphalt containing high RAP content (50%).


• Project 9-47: Evaluation of the Environmental and Engineering Properties of Warm Asphalt Technologies(1) Evaluate the type and level of emissions from WMA during production and placement. (2) Correlate the engineering properties of WMA to field performance. (3) Compare the initial performance of WMA to HMA.


• Project 4-35: Enhanced Test Method for Specific Gravity and Absorption of Coarse and Fine Aggregates

Develop an enhanced a method of test for specific gravity and absorption of coarse and fine aggregates.

NCHRP FY 2008 ProgramNCHRP FY 2008 Program• March 25-27, 2008: FY 2008 projects selected• April 2007: Program announcement• April 13, 2007: Solicit panel nominees• National Academies acceptance• Panel formation• July-December 2007: 1st and 2nd panel meetings

(develop RFPs and select agencies)• February 1, 2008: FY 2008 authorization• February-March 2008: Contracting

NCHRP FY 2009 ProgramNCHRP FY 2009 Program• July 2, 2007: Solicitation of FY 2009 problem

statements• Sept. 14, 2007: End date for problem statements• Nov. 16, 2007: Respond to submitters• December 3, 2007: End date for submitter comment• January 3, 2008: Mail candidates to SCOR/RAC• February 19, 2008: SCOR/RAC ballots due• March 6, 2008: Ballot summary report to SCOR• March 25-27, 2008: SCOR meeting/project selection

More InformationMore Information

• Cooperative Research Programs" (CRP) WWW Homepage

• http//www.trb.org .……. NCHRP

• Contact: Amir N. [email protected]/334-1892

seminar effectiveness discussion - transportation

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