Request for Proposal (RFP)
Posted February 20, 2003

Requests Closed 4/21/03 at 4:00 PM (EST)

IPRF Project 01-G-002-02-1

Design Guide and Recommendations for the Use of Stabilized and Drainable Sub-base In Rigid Pavement Systems (Design, Specification, and Construction)

Requests Closed


The Federal Aviation Administration (FAA) requires the owner to include a stabilized sub-base in pavements that see traffic by aircraft weighing more than 100,000 pounds. The Department of Defense (DoD) requires all new airfield pavement construction to include a drainable base (sub-base). In some regions of the country drainable base is being included in private sector airfield pavements. It is also a common practice to use an asphalt leveling course for overlay pavement or as asphalt stabilized base. Experience demonstrates that some pavements that incorporate a stabilized or open graded sub-base experience early cracking (within 90 days). There appears to be a consensus among design professionals and constructors that the early cracking is the result of excessive sub-base strength and high friction between the plastic concrete and the sub-base. There is some research that provides evidence that smaller joint spacing is required when stabilized base and open-graded materials are used as sub-base. Design and construction guidance on the design and construction of stabilized and open graded sub-base is required.


The final product will be a document that provides design and construction criteria for incorporating stabilized and open-graded sub-base materials as a part of the airfield rigid pavement structure. Draft Advisory Circulars for implementing the requirements will be developed by the investigator. The investigator will successfully demonstrate the adequacy of the design criteria and the constructability of stabilized and open-graded systems by building full scale test pavements using the criteria outlined in the guide and draft Advisory Circular(s). Full scale construction demonstration tests will not be included as a part of an active airfield pavement project.

At the conclusion of the research there should be a document(s) that the engineer or constructor can read and gain an understanding of the materials used and the design criteria to apply to specify the construction of a stabilized or open-graded sub-base. The criteria and the techniques necessary should result in a pavement system that will provide the owner the expected level of service.

The investigator will provide two originals, in a camera ready format, of the documents developed under this program including any artwork, graphics or photos. There will also be a submittal in an electronic format compatible with off-the-shelf desktop computer publication software. The investigator will not be responsible for the reproduction and printing of the final document(s) but will assist with minor editing requirements generated by the printing and reproduction process.

The investigator will develop sub-tasks that when completed will result in completion of the project within the time and budget available. It is not necessary that the proposal reflect the exact budget or the planned time. However, any deviation from the designated resources must be justified and clearly explained in the proposal. The following are the minimum tasks that are considered necessary to complete the project.

Task 1 - Literature and Airport Project Review. Review existing literature and/or source documents from which engineers determine materials compatibility, thickness, strength, and construction acceptance criteria for both stabilized and open graded layers. For the purpose of this study, stabilized materials will include cement stabilized base, cement treated base, and asphalt treated base. Open graded materials are those with an aggregate gradation developed for the purpose of promoting positive drainage. Open graded materials may be stabilized or granular graded materials.

Identify airports that have constructed stabilized and open graded sub-base in pavement systems. Determine from project reviews the variables that may or could demonstrate the success and failure variables related to design and construction of stabilized and open-graded sub-base. Identify candidate airport projects for further investigation.

IMPORTANT: The investigator will not accomplish the initial data acquisition by conducting a written survey. A survey is defined as the random distribution of a standard list of questions that seek trends or forecasting information. The use of such surveys must receive approval through the IPRF from the Office of Management and Budget (OMB). That process requires a minimum of 90 days from the date of application for the survey approval. The 90 day approval period is not included in the time designated as the performance period. The investigator is encouraged to use a means other than "survey" to identify the candidate airport projects.

Task 2 - Project Identification. Develop a list of projects at airports that could be included in a detailed study. The list must include scope, cost, owners, planners, designers, and constructors (all stakeholders). The list must include projects at airports representing the Federal Aviation Administration (FAA) definitions for the different categories of commercial airports and General Aviation airports. The list should include a recommendation by the investigator as why projects are included in a detailed study and what information will be gleaned. The list of projects should include pavements that are performing and those that experienced some early distress. The list will be submitted to the IPRF for review and concurrence at the 20% review.

Task 3 - Document a Research Plan. Develop a plan for gathering data from the project list. Determine what information is to be gathered and from whom.

A 20% on-board review will be accomplished. The investigator will not proceed to Task 4 without the written approval of the IPRF. The on-board review must be scheduled at least 30 days prior to the actual meeting. Documents that are prepared for technical panel review must be provided at least 30 days prior to the meeting. The location of the meeting will be coordinated with the IPRF. The investigator is responsible for documenting the comments of IPRF technical panel members and the disposition of each comment.

Task 4 -Pavement Performance Interviews. Conduct interviews with the stakeholders and consolidate data. The materials incorporated in the pavement system will be documented and the placement conditions must be described. The pavement capacity in terms of gear load and gross weight should be used to provide category divisions for pavements.

Develop a draft report that includes a summary of the projects studied and the lessons learned from the studies. Determine the characteristics that lead to acceptable construction and pavement performance. Prepare a design guide for the use of stabilized and open-graded materials as layers in the rigid airport pavement system. Develop Draft Advisory Circulars to be used as the implementing tools of the design guide.

A 60% on-board review will be accomplished. The review will be a meeting between the investigator and the IPRF Technical Panel. The draft report will be provided to the technical panel at least 30 days prior to the meeting. The investigator is expected to present to the technical panel discussion items that will result in policy decisions for critical elements of the final report. Additional research may be needed to respond to questions that are developed as a result of the on-board review. The location of the meeting will be coordinated with the IPRF. The investigator is responsible for documenting the comments of IPRF technical panel members and the disposition of each comment.

Task 5 - Demonstration of Constructability. The investigator shall provide a site for and pay for the construction of a minimum of three (3) full scale pavement cross-sections. The purpose of the cross sections will be to demonstrate that rigid pavements can be constructed using the design guide and the draft specifications (Advisory Circular) and that the intent of the design criteria can be realized using locally available materials. The demonstration will be accomplished with techniques that use conventional construction equipment. The test sections will include the construction of a Portland cement concrete surface course. The constructability, response to construction traffic, and acceptance criteria used for the sub-base construction will be evaluated. The design guide and the draft specifications will be modified using the lessons learned in the full scale test construction.

Task 6 - Advanced Final Design Guide(s). Make corrections using the 60% review, additional data gathered as a result of the 60% review and the test construction. Include in the 90% report all artwork, graphical presentations, format, etc. The 90% document shall be in a form that for all intent is complete with the exception of final comments made by the technical panel.

A 90%on-board review will be accomplished. The review will be a meeting between the investigator and the IPRF Technical Panel. The draft design guide(s) (as an IPRF Report) and specifications (in the form of Advisory Circulars), will be provided to the technical panel at least 30 days prior to the meeting. The location of the meeting will be coordinated with the IPRF. The investigator is responsible for documenting the comments of IPRF technical panel members and the disposition of each comment.

Task 7 - Final Report. Make corrections to the 90% document and submit the final documents to the IPRF. Assist the IPRF with publication related editing.

Products Summary:

1. A final report in the form of design guides (an IPRF Report) and recommended specifications (Advisory Circular) complete with all artwork, graphics, tables, pictures, documentation, etc. ready for reproduction and distribution. The final documents will address material characteristics, thickness and pavement details for design criteria for stabilized/open-graded sub-base. The guidelines will also include recommendations for thickness design and jointing considerations for rigid pavement. The report will be submitted in two original documents and one on electronic media.

2. A list of projects and a proposed research plan. Submit 8 copies. This is defined as the 20% level of completion. The project list and the proposed methods on obtaining information will be reviewed at an on-board meeting at a location to be determined. The investigator will host the meeting. Location will be determined in coordination with the IPRF.

3. The 60% on-board review will be accomplished approximately 30-days after submittal of a draft report. The draft report (8 copies) will include a summary of data collected and recommended discussion items. The investigator will host the meeting. Location will be determined in coordination with the IPRF.

4. Advanced final report submittal (8 copies) and 90% on-board review. The investigator will host the meeting. Location will be determined in coordination with the IPRF.

5. Final report review (8 copies) and comment by IPRF technical panel.

Other Considerations and requirements:

1. The investigator will be responsible for the preparation of quarterly reports that describe the progress of the research effort. Reports are due in the offices of the IPRF on the last day of the fiscal year quarter. The reports will be limited to two pages in a format specified by the IPRF. The first page will be a word document describing the progress of the work. The second page will provide a summary of the estimated costs versus the costs incurred to the report date.

2. Because of the limited resources, it is not possible to have an exhaustive list of projects to document. Therefore, in proposing candidate projects, the investigator should consider thermal regimes (sub-tropical, central, and northern tier), pavement features (taxiways, intersections, runways, aprons), and projects that involve rehabilitation and reconstruction.

3. The investigator will define the terms "stabilized" and "open-graded." The terms must relate exactly what combination of materials and properties will result in the defined sub-base (base). The definition must include guidelines for the use of chemical stabilization. Included in the definition of open-graded (OG) materials will be the limits for permeability (rate and time). The OG guide must define the correct use of a drainable layer for intercepting infiltration or capillary water.

4. Considerations for elements that should be included in the design guides should be based upon materials selection, intent of the system, and the expected quality of the pavement system. As a minimum the elements should include:

  • Planning
  • Strength Issues
  • Design
  • Cost
  • Time
  • Quality
  • Bond Breakers
  • Joint Spacing
  • Material Sensitivity
  • Material Gradations
  • Frost Design
  • Construction and Ambient Temperature and Season Change
  • Joint Load Transfer Efficiency
  • Schedule for Saw Cutting
  • Engineering Characteristics of Systems
  • Innovation in Materials
  • Techniques
  • Safety
  • Performance
  • Quality Controls and Acceptance Criteria
  • Incentives (Penalty or Bonus)
  • Risk Assumptions
  • Pavement Penetrations
  • Construction Sequences
  • Opening to Traffic
  • Use of Recycled Materials
  • Geotextiles

5. The investigator will initiate contact with the airports that are selected for detailed study and documentation of projects through the IPRF. The investigator will provide a draft letter. The IPRF will edit the letter of introduction to the airports and may include an endorsement of the letter by the FAA. This is intended to encourage participation by the airports and their sponsors.


After the technical panel completes the evaluation of proposals, each of the proposals will be rank ordered. The organization, group, or individual that is ranked as the first and second choice for the recommendation to award may be asked to make a presentation to the project technical panel. The Principal Investigator, and one other person, representing the entity ranked first and second choice by the technical panel may be asked to participate in an interview to discuss the project details, goals, and objectives. The IPRF will reimburse the expenses (up to 2 people) to make this presentation at a location yet to be determined. The interview will occur within a 45-day window subsequent to the proposal submittal deadline.


IPRF procedural guidance documents are available on the web at in the section titled "Airfields Research." Persons preparing proposals are urged to review the following documents to be sure that there is a full understanding of IPRF procedures and requirements. Proposals must be prepared in the format specified in the instruction documents. The proposal will be submitted as one (1) original and 8 copies.

The documents required as an aide to the preparation of the proposal include:

PDF files require Acrobat Reader to view.

FUNDS AVAILABLE: Not to Exceed $425,000

CONTRACT TIME: Not to exceed 14 Months

PROJECT DIRECTOR: James L. Lafrenz, P.E., (202) 842-1131,


PROPOSAL DUE DATE: April 21, 2003 not later than 4:00 P.M. (Eastern Time)


Proposals will be delivered to:
Innovative Pavement Research Foundation
Cooperative Programs Office
1010 Massachusetts Ave., N.W., Suite 200
Washington DC 20001
(202) 842-1131
FAX: (202) 842-2022
Attention: Research Proposal Log

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