Rubblization technology and equipment was initially developed for highway pavements, however, there is interest in using this technology to rehabilitate aging airfield pavements as well. Airfield Portland cement concrete pavements (PCCP) often have significantly greater thicknesses as compared to highway PCCP. Within the FAA Integrated Airport System airfield infrastructure and the U.S. Defense Department airfield inventory, there are more than 83 million square meters (100 million square yards) of PCCP greater than 33 cm (13 inches) thick and more than 35 years old. These aging pavements will likely need major rehabilitation within the next 10 years.

Recently, the FAA and the Air Force published the following guidance on the use of rubblization for airfield pavements:

1. FAA Engineering Brief No. 66 Rubblized Portland Cement Concrete Base Course, Published February 13, 2004.
2. Air Force Engineering Technical Letter ETL (01-9): Procedures to Retard Reflective Cracking, Published July 17, 2001.

The successes and problems associated with design, construction, and quality control, of rubblized pavement structures need to be quantified along with information from the use of rubblized highway pavements.

Objectives

The objective of this research is to document rubblization technology and prepare a guide specification and a design and construction manual for use by engineers involved in the design and construction of airfield pavements.

Product

The product of this research will be a final report in the form of a manual and guide specification that will provide proper construction criteria, design features, detailed guide specifications, and appropriate methods for quality control and quality assurance for an airfield project using rubblization.

Tasks

Phase I

Task 1. Collect, review, and synthesize information relative to rubblization of PCC pavements with special emphasis on airfield pavements. The rubblization process has been used extensively on highway projects and the successful research team should utilize the knowledge gained from that work to enhance the results of this project. This review will include but not be limited to:

1. A review of the existing state of practice to include as a minimum a review of the technical literature, a review of specifications being used for rubblization projects and where appropriate have discussions with contractors and agencies that have designed and completed rubblization projects. Include in this effort a comparison of the key features of the specifications.
2. A review of construction projects where rubblization has been used. This review should include information on successes/failures, design and construction problems, key features (for example drainage systems), etc. Include information on both airfield and highway projects with emphasis on airfields.

1. When is rubblization the feasible/appropriate rehabilitation approach for airfield pavement?
2. Develop a decision tree (or flow chart) to assist in the design of a rubblized layer and to assist in the design of pavements using rubblized layers.
3. General aviation/auxilliary airfields -- Review and develop guidance for the use of rubblized concrete pavement as a base material for small or light duty airports.
4. Commercial services -- Review and develop guidance for the use of rubblized concrete pavement as a base material for large or heavy duty civilian airports and military airfields.
5. How should the characterization of the structural contribution of the rubblized layer be handled.
   1. Procedures used for characterizing the structural contribution of the rubblized layer, limitations of current procedures and identify new procedures for determining structural characterization of the layer.
   2. Review the impact of subgrade support on the properties of rubblized concrete materials. How does the subgrade support impact the construction of rubblized concrete materials? What influence will strong or weak subgrades have on the constructed rubblized layer?
   3. Necessity for drainage of rubblized layers.
   4. Suggested design procedures must be compatible with future and current FAA and DOD design procedures and usable for both general aviation and commercial airfields.

Task 3. Describe procedures that have been used for quality control of rubblized projects and identify limitations with existing quality control practices. Identify new quality control concepts and construction procedures that may result in improved uniformity of the final product. The possibility of performance specifications versus prescriptive construction specifications should be investigated.

Task 4. Define in general terms how the following will be addressed in the final manual:

1. Drainage design and the installation of a drainage system
2. Underground utilities (electrical conduit, drainage structures, etc.)
3. Rubblization and seating equipment
4. Construction sequence
5. Leveling courses
6. Relief trenches
7. Seating process or compaction of rubblized layer
8. Procedures for dealing with unstable areas
9. Handling of traffic
10. Proof rolling

Phase II

Task 6. Upon direction of the Technical Project Panel, the research agency will prepare the detailed manual. The final manual will include the following:

1. A guide specification for rubblization of concrete pavement in FAA format along with an engineering commentary.
2. A design and construction manual which will include, but not necessarily be limited to, the following:
   1. Comprehensive guidance on design and construction using the rubblization process.
   2. Best practices guide for construction (a best practice is defined as a bullet listing of the optimal or alternative solutions to common situations encountered during design or construction).
   3. Best practices guide for design of pavement when the rubblization process is used.
   4. An outline method for a life cycle cost analysis.
   5. Executive summary (two to three pages in length).
   6. Decision tree for feasibility of rubblization.

Task 7. The FAA is conducting a study at their research facility in Atlantic City that will include the construction of a test section that includes the placement of an HMA overlay over a rubblized section of PCC pavement and an overlay over a PCC pavement that has not been rubblized. The FAA is conducting extensive testing on these sections and will be trafficking them with simulated airfield traffic. The research agency will utilize the FAA data and prepare a separate report that analyzes and describes the work being done in Atlantic City and the results of the study. The research team should designate up to $25,000 of the total amount of their proposal for this support. The points of contact at the FAA Technical Center are Gordon Hayhoe at 609-485-8555 for testing and Robert (Murphy) Flynn at 609-485-5318 for construction. E- mail addresses are gordon.hayhoe@faa.gov and robert.flynn@faa.gov.

Task 8. Upon completion of the project a final report will be required. The research agency should submit a preliminary draft (8 hard copies and one electronic copy) for review by the Project Technical Panel. Upon completion of this review, comments will be provided to the research agency. Approximately one month after the research agency has received and reviewed the comments from the Project Technical Panel, a meeting will be set up for the Project Technical Panel and the research agency to review the project findings and the final report. The research agency should be prepared to make a presentation at this meeting that will cover all aspects of the project. Within thirty days of this meeting, the research agency will submit to AAPTP a final report that incorporates the reviewers' comments and reflects editing by a competent technical editor. All reports will be submitted in both hard copy and electronic copy format. All written documentation will be prepared using Microsoft Word. All reports will be the property of the Federal Aviation Administration and will be supplied in a format that complies with the agency's Section 508 requirements for electronic documents. A policy statement for Section 508 can be found at http://www.faa.gov/aio/508/, and the Section 508 website, a summary and list of standards, can be found at http://www.section50 8.gov/index.cfm?FuseAction=Content&ID=3.

REPORTING REQUIREMENTS

Progress reports

Quarterly progress reports (2 hard copies and an electronic copy in Microsoft Word format) are required from the research agency and are to be prepared on the basis of calendar quarters. The research agency will mail the 2 hard copies of the report directly to the AAPTP and will E-mail each of the members of the technical review panel a copy of the progress report. Each report will include the following: A cover letter providing (a) a clear and complete description of the work performed on each task during that quarter; (b) an outline of the work to be accomplished during the next quarter; (c) a description of any problem(s) encountered or anticipated that might affect the completion of the project within the designated time and fiscal constraints and (d) recommended solutions to problems identified in (c) if any exist.

Report Format

Follow the format for the final report shown here. Interim reports should follow the same format.

SELECTION OF CONTRACTORS

The evaluation considers the following: (1) the research agency's demonstrated understanding of the problem; (2) the merit of the proposed research approach to the solution of the problems outlined in the RFP; (3) experience, qualifications, and objectivity of the research team in the same or closely related areas; and (4) the breakdown of manpower and costs. The total funds available are made known in this problem statement, and line items of the proposed budget will be examined to determine the reasonableness of the allocation of funds to the various tasks.

CONTRACTUAL INFORMATION

The technical portion of the proposal should not exceed 20 pages.

Funds available: $200,000

Eight copies of proposal due no later than 4pm CST on June 24, 2005

Contract time: 24 months (Phase I -- 12 months, which includes 1 month for the Project Technical Panel to review and approval of the outline; Phase II--12 months, which includes 3 months for Project Technical Panel to review, and for the contractor to revise, the final report.)

Staff responsibility: E. Ray Brown, 334-844-6228, brownel@eng.auburn.edu

Authorization to begin work: August 2005 -- estimated

Send proposals to the following address:

E. Ray Brown
AAPTP
277 Technology Parkway
Auburn, AL 36830
Email: brownel@eng.auburn.edu