The National Aeronautics and Space Administration (NASA) Modern-Era Retrospective Analysis for Research and Applications version 2 (MERRA-2 ) utilized data from the Earth Observing System satellites to improve precipitation and water vapor climatology beginning in 1979. The Federal Highway Administration (FHWA) and the American Association of State Highway Transportation Officials (AASHTO) have adopted its use and translated the variables into civil engineering applications, specifically pavement design. FHWA’s Long Term Pavement Performance (LTPP) Climate Tool provides access to the MERRA-2 database and generates site-specific climate data in compatible formats for AASHTO Pavement ME Design (Pavement ME). AASHTO will soon use MERRA-2 climatic data for AASHTOWare applications. MERRA-2 data sets include accurate hourly solar radiation values based on measured cloud-covered fractions which can significantly improve the accuracy of predicted pavement temperatures.
Studies reveal challenges in matching the predictions from the Enhanced Integrated Climatic Model (EICM) with field observations and pavement performance. Variations in measurement of climatic attributes have also been reported to Operating Weather Stations (OWS). MERRA-2 data provides opportunities for enhancements to the climatic parameters and climatic module calculations for pavement design using Pavement ME. It provides improved climatology, higher frequency outputs including hourly data updates, and additional locations beyond the United States. Available data categories include: temperature, precipitation, surface pressure, cloud cover, humidity, wind speed, and solar radiation.
The objectives of this project are to (1) evaluate the impact of using NASA’s Modern-Era Retrospective Analysis for Research and Applications version 2 (MERRA-2) through the FHWA LTPP Climate Tool to improve the climatic inputs and related models for Pavement ME; (2) enhance and simplify climate input parameters for Pavement ME that can be implemented by transportation agencies; and (3) develop climate-related models based on identified parameter enhancements.
The NCHRP is seeking the insights of proposers on how best to achieve the research objectives. Proposers are expected to describe research plans that can realistically be accomplished within the constraints of available funds and contract time. Proposals must present the proposers' current thinking in sufficient detail to demonstrate their understanding of the issues and the soundness of their approach to meeting the research objectives.
The research plan should: (1) include a kick-off teleconference with the research team and NCHRP convened within 1 month of the contract’s execution; (2) address the manner in which the proposer intends to satisfy the project objectives; (3) be divided logically into detailed tasks that are necessary to fulfill the research objectives and include appropriate milestones and interim deliverables; and (4) incorporate opportunities for the project panel to review, comment, and approve milestone deliverables.
At a minimum, the research plan shall include the following tasks:
Task 1. Conduct a literature review related to modeling the impact of the climatic input parameters for pavement design and application of NASA MERRA, MERRA-2, and subsequent versions in pavement design.
Task 2. Assess the state of practice including challenges encountered by state transportation agencies using Pavement ME relative to climate data.
Note: A brief survey prepared by the contractor and administered by NCHRP may be distributed to state transportation agencies that use Pavement ME Design.
Task 3. Identify limitations of existing climatic inputs and related models for Pavement ME.
Task 4. Evaluate the use of MERRA-2 data from FHWA LTPP Climate Tool in the calibration of the climatic-related models used in the Pavement ME.
Task 5. Based on the findings of Tasks 3 and 4, identify potential enhancements to the climatic inputs and related models for Pavement ME, using data from MERRA-2. For example, evaluate the use of MERRA-2 data that includes shortwave radiation inputs to predict pavement temperature, versus use of empirical relationships embedded in applications like the Pavement ME and LTPPBind.
Task 6. Prepare an interim report that documents the work completed in Tasks 1 through 5. Include a detailed work plan for the work anticipated in Phase II.
1. NCHRP approval of the proposed Phase II work plan is required prior to initiation. This shall occur at a face-to-face meeting to be convened in Washington, D.C. at TRB offices. TRB will cover the costs associated meetings at TRB facilities, teleconference services, and any approved panel travel.
2. For availability of Pavement ME Design software, see Special Note I.
Task 7. Improve and simplify the climate input parameters for Pavement ME that can be implemented by transportation agencies.
Task 8. Develop enhancements of climatic inputs and related models for future incorporation in Pavement ME including developing appropriate functional requirements and software engineering related criteria.
Task 9. Validate any new or enhanced model(s).
Task 10. Arrange coordination and provide opportunities for review and approval of enhancements by NCHRP and AASHTO.
Task 11. Prepare final deliverables.
Final Deliverables should include:
1. A stand-alone deliverable that includes the enhanced climatic models and related input parameters;
Note: If applicable, include any source code, databases, programs, software, software documentation, and cleaned data sets developed under this project in USB or other pre-approved format.
2. A final report documenting the entire research effort including prioritized recommendations for future research;
3. An executive summary of the project;
4. A PowerPoint presentation describing the background, objectives, research approach, findings, and conclusions; and
5. A stand-alone technical memorandum titled “Implementation of Research Findings and Products” (see Special Note D for additional information).
Proposers may recommend additional deliverables to support the project objective.
A. Item 4 of the proposal, the Research Plan, shall not exceed 25 pages, in 12-point Arial font or larger. Item 5 of the proposal shall be limited to 1 page of biographical information for each person.
B. Proposals should include a task-by-task breakdown of labor hours for each staff member as shown in Figure 4 in the brochure, "Information and Instructions for Preparing Proposals" (http://onlinepubs.trb.org/onlinepubs/crp/docs/ProposalPrep.pdf). Proposals also should include a breakdown of all costs (e.g., wages, indirect costs, travel, materials, and total) for each task using Figures 5 and 6 in the brochure. Please note that TRB Cooperative Research Program subawards (selected proposers are considered subawards to the National Academy of Sciences, the parent organization of TRB) must comply with 2 CFR 200 – Uniform Administrative Requirements, Cost Principles, and Audit Requirements for Federal Awards. These requirements include a provision that proposers without a "federally" Negotiated Indirect Costs Rate Agreement (NICRA) shall be subject to a maximum allowable indirect rate of 10% of Modified Total Direct Costs. Modified Total Direct Costs include all salaries and wages, applicable fringe benefits, materials and supplies, services, travel, and up to the first $25,000 of each lower-tier subaward and subcontract. Modified Total Direct Costs exclude equipment, capital expenditures, charges for patient care, rental costs, tuition remission, scholarships and fellowships, participant support costs and the portion of each lower-tier subaward and subcontract in excess of $25,000.
C. NCHRP wishes to award the contract for NCHRP Project 20-50(21) for a fixed price of $350,000. This amount will not be subject to any adjustment by reason of the contractor’s cost experience in the performance of the contract. In addition to providing a detailed budget, the proposer should provide a proposed schedule of project milestones, deliverables, and progress payments tied to the detailed budget and schedule which will be inclusive of specific dates. For budgeting purposes, proposers should assume that (1) NCHRP will provide access to web-enabled teleconference services and (2) 1 in-person meeting with the NCHRP project panel will be held in Washington, DC. NCHRP will pay panel members’ travel costs for the meeting.
D. The NCHRP is a practical, applied research program that produces implementable products addressing problems faced by transportation practitioners and managers. The benefits of NCHRP research are realized only when the results are implemented in state DOTs and other agencies. Implementation of the research product must be considered throughout the process, from problem statement development to research contract and beyond completion of the research. Item 4(c), "Anticipated Research Results," must include the following: (a) the "product" expected from the research, (b) the audience or "market" for this product, (c) a realistic assessment of impediments to successful implementation, and (d) the institutions and individuals who might take leadership in deploying the research product. The project panel will develop and maintain an implementation plan throughout the life of the project. The research team will be expected to provide input to an implementation team consisting of panel members, AASHTO committee members, the NCHRP Implementation Coordinator, and others in order to meet the goals of NCHRP Active Implementation: Moving Research into Practice, available at http://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP_ActiveImplementation.pdf.
E. Item 5 in the proposal, "Qualifications of the Research Team," must include a section labeled "Disclosure." Information relevant to the NCHRP's need to ensure objectivity and to be aware of possible sources of significant financial or organizational conflict of interest in conducting the research must be presented in this section of the proposal. For example, under certain conditions, ownership of the proposing agency, other organizational relationships, or proprietary rights and interests could be perceived as jeopardizing an objective approach to the research effort, and proposers are asked to disclose any such circumstances and to explain how they will be accounted for in this study. If there are no issues related to objectivity, this should be stated.
F. Proposals are evaluated by the NCHRP staff and project panels consisting of individuals collectively very knowledgeable in the problem area. Selection of an agency is made by the project panel considering the following factors: (1) the proposer's demonstrated understanding of the problem; (2) the merit of the proposed research approach and experiment design; (3) the experience, qualifications, and objectivity of the research team in the same or closely related problem area; (4) the plan for ensuring application of results; (5) the proposer's plan for participation by Disadvantaged Business Enterprises--small firms owned and controlled by minorities or women; and (6) the adequacy of the facilities.
Note: The proposer's plan for participation by Disadvantaged Business Enterprises should be incorporated in Item 12 of the proposal.
G. Copyrights - All data, written materials, computer software, graphic and photographic images, and other information prepared under the contract and the copyrights therein shall be owned by the National Academies of Sciences, Engineering, and Medicine. The contractor and subcontractors will be able to publish this material for non-commercial purposes, for internal use, or to further academic research or studies with permission from TRB Cooperative Research Programs. The contractor and subcontractors will not be allowed to sell the project material without prior approval by the National Academies of Sciences, Engineering, and Medicine. By signing a contract with the National Academy of Sciences, contractors accept legal responsibility for any copyright infringement that may exist in work done for TRB. Contractors are therefore responsible for obtaining all necessary permissions for use of copyrighted material in TRB's Cooperative Research Programs publications. For guidance on TRB's policies on using copyrighted material please consult Section 5.4, "Use of Copyrighted Material," in the Procedural Manual for Contractors.
H. Proposers are expected to be familiar with the following and to take them into account when developing the proposed research plan:
1. LTPP Climatic Tool: presents MERRA-2 data for pavement applications and more: https://infopave.fhwa.dot.gov/Data/ClimateTool; Tec brief is available at: https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/17011/index.cfm
2. Evaluation of LTPP Climatic Data for Use in Mechanistic-Empirical Pavement Design Guide Calibration and Other Pavement Analysis: Report: https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/15019/index.cfm; Tech Brief: https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/15026/index.cfm
I. Any computer software development must be conducted in collaboration with AASHTO representatives to ensure compatibility with AASHTOWare legacy systems.
AASHTOWare Pavement ME Design and the Mechanistic-Empirical Pavement Design Guide: A Manual of Practice, Second Edition (Item Code MEPDG-2) are available from the American Association of State Highway and Transportation Officials (AASHTO), 444 N. Capitol Street, NW, Washington, DC 20001. The Pavement ME Design software will be provided to the selected contractor at no cost to the project. However, $2,000 should be allocated for charges in connection with installation and tech support.
The selected contractor shall provide protocols for testing, maintenance and troubleshooting and deliver the following derived products if applicable: (1) developed computer databases, (2) programs, (3) software (including source code, object code listings, design details, algorithms, processes, flow charts, formulae, and related material that would enable the software to be reproduced), and (4) software documentation developed during this research study. These deliverables shall become the exclusive property of the National Academies of Sciences, Engineering, and Medicine. Anything proprietary shall be disclosed at the onset of this project and all parties shall agree to its use.