The National Academies

NCHRP 25-66 [RFP]

Reviewing the REMEL Noise Database to Accommodate the Current Vehicle Fleet

Posted Date: 12/19/2022

  Project Data
Funds: $1,000,000
Contract Time: 30 months
(includes 1 month for NCHRP review and approval of each interim report and 3 months for NCHRP review and for contractor revision of the final report)
Authorization to Begin Work: 7/1/2023 -- estimated
Staff Responsibility: Dr. Zuxuan Deng
   Phone: 2023342305
   Email: zdeng@nas.edu
RFP Close Date: 2/6/2023
Fiscal Year: 2023



Highway noise is always a top environmental concern with the public on any highway project. The Reference Energy Mean Emission Level (REMEL) database is an inventory of different vehicle pass-by noise levels that is the basis for the Federal Highway Administration (FHWA) Traffic Noise Model (TNM) analysis software. It is 25 years old and in need of updating due to changing vehicle fleet characteristics. Newer noise measurement technology has also evolved, and it can be applied to locate and quantify noise generators on a moving vehicle. The REMEL database directly affects noise impact and mitigation analyses on federal-aid projects. 

Research is needed to update the highway noise dataset using existing and new highway acoustic measurement technologies to account for the change in the vehicle fleet. 


The objective of this research is to update the REMEL noise database to account for new vehicle fleet with focus on 

  1. Newer passenger car (PC) types, 
  2. Medium truck (MT), 
  3. Heavy truck (HT), and
  4. Electronic vehicle (EV).

At a minimum, the research team should use three acoustic measurement technologies (beamforming, wayside sound level, and on-board sound intensity [OBSI]) that will better quantify the position and distribution of vehicle noise sub-sources: mechanical, exhaust, tire/pavement, and aerodynamic sources.


Accomplishment of the project objective will require completion of the following tasks, at a minimum.




Task descriptions are intended to provide a framework for conducting the research. The NCHRP is seeking the insights of proposers on how best to achieve the research objective. 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 objective. Proposers must be aware of current measurement standards, be capable of applying such knowledge to develop new standards, justify their choice when options are available in the following tasks, and demonstrate an understanding of the potential impact of this work on national noise impact and abatement decisions. Proposers must also specify equipment that will be used and whether they have access to all of the necessary equipment and software (note that the USDOT Volpe Center has OBSI equipment available for loan).




Task 1. Review the pertinent literature on computational and acoustical source visualization methodologies; highway noise measurement, practices, and techniques; and the latest industry standards of acoustical source characterization and vertical distribution of sound energy at source. Identify ongoing, relevant research projects and obtain any interim materials, if available. Identify any needed coordination with other ongoing research projects.


Task 2. Develop or identify standardized methodologies for beamforming, wayside sound level (isolated passby), and OBSI, and for acoustical source characterization and vertical distribution (from 0 to 14 ft) of sound energy at source that determine the optimal microphone array resolution and frequency range of the system. Describe validation and calibration methodologies for all three noise measurement technologies. Beamforming measurements should be accompanied and be conducted simultaneously with wayside measurements.


Task 3. Submit a technical memorandum summarizing findings from Tasks 1 and 2.


Task 4. Conduct a virtual meeting with the NCHRP panel to discuss findings from Tasks 1 and 2. Receive feedback and guidance to proceed with Task 5.


Task 5. Develop a detailed data collection plan. At a minimum, the plan should cover:


Measurement Sites

  • Number of sites (minimum 4 pavement types x 5 regions) for each pavement type (at minimum: dense-grade asphaltic concrete [DGAC], open grade asphaltic concrete [OGAC], and Portland cement concrete [PCC] (longitudinally tined concrete and transverse tined concrete) in good condition)
  • Site characteristics, similar to descriptions given in FHWA-PD-96-008: Development of National REMEL for the FHWA TNM Section
  • Recommend geographically diverse locations to represent national fleet and landscape varieties ·        


Vehicle Characteristic

  • Vehicle type: PC, MT, HT (high and low exhaust), and any bus or motorcycles that come through
  • Number of axles
  • Propulsion type: internal combustion engine (ICE)/electronic/hybrid
  • Operating Condition
  • Idle
  • Constant flow speed range, e.g., 25 to 85 mph
  • Acceleration for all vehicle types
  • Truck crawling for high roadway grade·        


Data Collection

  • Device placement of wayside SLM and beamforming array, e.g., for wayside SLM: 25 ft and 50 ft from the center line of the nearest travel lane at height of 5 ft and 12 ft,
  • On-site verification and reporting of proposed sites
  • Applicable frequency ranges, e.g., 50 to 10,000 Hz for wayside SLM, 400 to 5000 Hz for OBSI and 500 to 10,000 Hz for beamforming or better if available
  • Non-acoustic data: vehicle speed, meteorological, video, synchronized time log, data logs, site location (latitude, longitude, elevation), etc.
  • Quality assurance and quality control plan
  • Minimum data for each vehicle/operating condition/pavement type, e.g., 30 events for uncommon conditions such as MT/constant flow between 25 and 30 mph/OGAC and 100 events for common conditions such as auto/constant flow between 55 and 60 mph/DGAC          


Dataset Structure and Format 

  • Open-source digital format for immediate use by state DOTs and public
    • E.g., wayside sound level meter (SLM): max one-third octave A-weighted equivalent sound level (LAeq)-1/2 sec, maximum A-weighted fast time averaged sound level (LAfmax) time history for full pass by (-10, max, -10 dB) at ½ sec intervals
    • E.g., OBSI, final one-third octave sound intensity level (SIL) results for each test section
    • E.g., beamforming, overall and one-third octave band level distributions as a function of height
  • All relevant non-acoustic data
  • See Special Note A


Task 6. Prepare Interim Report No. 1 documenting the results of Tasks 1 through 5 and provide an updated plan for the remainder of the research no later than 6 months after contract award. The updated plan must describe the approved methodology and rationale for the work proposed for Phases II and III. 


Note: Following a 1-month review of Interim Report No. 1 by the NCHRP, the research team will be required to meet virtually with the NCHRP project panel to discuss the interim report. Work on Phases II and III of the project will not begin until authorized by the NCHRP. Phase I budget shall not exceed $175,000.





Task 7. Execute the data collection plan based on approved Interim Report No. 1. Conduct bi-monthly status call with the NCHRP panel during the entire data collection period.

Task 8. Submit the three collected data sets (beamforming, wayside sound level, and OBSI) in a digital format as approved in Interim Report No. 1 and a summary of findings to the NCHRP.


Task 9. Document the differences in approach from the FHWA-PD-96-008: Development of National REMEL for the FHWA TNM report.


Task 10. Prepare an annotated outline for the NCHRP report. The measurement process, data collection and findings should be thoroughly documented, to be subsequently implemented by FHWA into the FHWA TNM software to improve its accuracy, be continually maintained, and be updated in the future.


Task 11. Prepare Interim Report No. 2 that documents Tasks 7 through 10 and provide an updated work plan for the remainder of the research no later than 18 months after approval of Phase I. The updated plan must describe the process and rationale for the work proposed for Phase III. 


Note: Following a 1-month review of Interim Report No. 2 by the NCHRP, the research team will be required to meet in person with the NCHRP project panel to discuss the interim report. Work on Phase III of the project will not begin until authorized by the NCHRP.  




Task 12. Prepare and submit the draft NCHRP report based on approved Interim Report No. 2 for the NCHRP panel’s review.


Task 13. Prepare the final deliverables including the following:

  1. Final NCHRP report;
  2. Final data sets, including raw data;
  3. Media and communication material (e.g., PowerPoint presentations, 2-page executive level flyer, graphics, graphic interchange format (GIF)s, press releases); and
  4. A stand-alone technical memorandum titled “Implementation of Research Findings and Products.” See Special Note J for additional information. Additional funding may be available for a follow-up contract on the implementation of the results.


Note: Following receipt of the draft final deliverables, the remaining 3 months shall be for NCHRP review and comment and for research agency preparation of the final deliverables.  




A. To ensure that data produced under this project are accessible, a data archiving and sharing plan shall be prepared by the agency performing the research. The plan must be submitted with Task 6 and shall include a description of expected activities, schedules, limitations, milestones, and required resources. Researchers should describe briefly the expected schedule for data production and archiving in the CRP permanent repository, the format of the final dataset, the documentation to be provided, and whether or not any analytic tools and/or results also will be provided. The plan must include a description of actions planned to ensure quality. Moreover, the plan must specify the resources required to archive and distribute the data expected to be obtained in the course of performing the research. In general, public release of data will not occur before full review and approval by the CRP. 

The data archiving and sharing plan must include the following sections:

• Background and significance.

• Expected data formats.

• Description of data archiving and quality assurance plan.

• Description of data sharing plan.

• Schedule for data archiving and public release of data.

• Milestones for the implementation of the plan.

• Resources and budget.

B. The Information and Instructions for Preparing Proposals for the Transportation Research Board’s Cooperative Research Programs were revised in May 2022. Please take note of the new and revised text which is highlighted in yellow.  


C. Proposals must be submitted as a single PDF file with a maximum file size of 10 MB. The PDF must be formatted for standard 8 ½” X 11” paper, and the entire proposal must not exceed 60 pages (according to the page count displayed in the PDF). Proposals that do not meet these requirements will be rejected. For other requirements, refer to chapter V of the instructions. 


D. The Information and Instructions for Preparing Proposals for the Transportation Research Board’s Cooperative Research Programs have been modified to include a revised policy and instructions for disclosing Investigator Conflict of Interest. For more information, refer to chapter IV of the instructions. A detailed definition and examples can be found in the CRP Conflict of Interest Policy for Contractors. The proposer recommended by the project panel will be required to submit an Investigator Conflict of Interest and Disclosure Form as a prerequisite for contract negotiations.  


E. Proposals will be rejected if any of the proposed research team members’ work for organizations represented on the project panel. The panel roster for this project can be found at https://www.mytrb.org/OnlineDirectory/Committee/Details/6745. Proposers may not contact panel members directly; this roster is provided solely for the purpose of avoiding potential conflicts of interest.  


F. Proprietary Products - If any proprietary products are to be used or tested in the project, please refer to Item 6 in the Information and Instructions for Preparing Proposals. 


G. Proposals are evaluated by the NCHRP staff and project panels consisting of individuals collectively knowledgeable in the problem area. The project panel will recommend their first choice proposal 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) how the proposer approaches inclusion and diversity in the composition of their team and research approach, including participation by certified Disadvantaged Business Enterprises; and, if relevant, (6) the adequacy of the facilities. A recommendation by the project panel is not a guarantee of a contract. The National Academy of Sciences (NAS - the contracting authority for the National Academies of Sciences, Engineering, and Medicine) will conduct an internal due diligence review and risk assessment of the panel’s recommended proposal before contract negotiations continue.  


Note: The proposer's approach to inclusion and diversity as well as participation by Disadvantaged Business Enterprises should be incorporated in Item 11 of the proposal. 


H. 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 Academy of Sciences. 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 Academy of Sciences. 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. 


I. Proposals should include a task-by-task breakdown of labor hours for each staff member as shown in Figure 4 in the Information and Instructions for Preparing Proposals. 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. 


J. The required technical memorandum titled “Implementation of Research Findings and Products” should (a) provide recommendations on how to best put the research findings/products into practice; (b) identify possible institutions that might take leadership in applying the research findings/products; (c) identify issues affecting potential implementation of the findings/products and recommend possible actions to address these issues; and (d) recommend methods of identifying and measuring the impacts associated with implementation of the findings/products. Implementation of these recommendations is not part of the research project and, if warranted, details of these actions will be developed and implemented in future efforts. 


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 


K. If the team proposes a Principal Investigator who is not an employee of the Prime Contractor, or if the Prime Contractor is proposed to conduct less than 50% of the total effort (by time or budget), then section five of the proposal should include: (1) a justification of why this approach is appropriate, and (2) a description of how the Prime Contractor will ensure adequate communication and coordination with their Subcontractors throughout the project. 


L. All budget information should be suitable for printing on 8½″ x 11″ paper. If a budget page cannot fit on a single 8½″ x 11″ page, it should be split over multiple pages. Proposers must use the Excel templates provided in the Information and Instructions for Preparing Proposals for the Transportation Research Board’s Cooperative Research Programs 


M. Selected contractor may be able to borrow OBSI equipment from FHWA/Volpe/State DOT without charge


Proposals must be uploaded via this link: https://www.dropbox.com/request/fTi2AYofyi4JILOdjyDG 
Proposals are due not later than 5:00 p.m. Eastern Time on 2/6/2023.

This is a firm deadline, and extensions are not granted. In order to be considered for award, the agency's proposal accompanied by the executed, unmodified Liability Statement must be in our offices not later than the deadline shown, or the proposal will be rejected.

Liability Statement

The signature of an authorized representative of the proposing agency is required on the unaltered statement in order for TRB to accept the agency's proposal for consideration. Proposals submitted without this executed and unaltered statement by the proposal deadline will be summarily rejected. An executed, unaltered statement indicates the agency's intent and ability to execute a contract that includes the provisions in the statement.

Here is a fillable PDF version of the Liability Statement. A free copy of the Adobe Acrobat PDF reader is available at https://www.adobe.com.

General Notes

1. According to the provisions of Title 49, Code of Federal Regulations, Part 21, which relates to nondiscrimination in federally assisted programs, all parties are hereby notified that the contract entered into pursuant to this announcement will be awarded without discrimination on the grounds of race, color, religion, sex, national origin, or disability.

2. The essential features required in a proposal for research are detailed in the current brochure entitled "Information and Instructions for Preparing Proposals". Proposals must be prepared according to this document, and attention is directed specifically to Section V for mandatory requirements. Proposals that do not conform with these requirements will be rejected.

3. The total funds available are made known in the project statement, and line items of the budget are examined to determine the reasonableness of the allocation of funds to the various tasks. If the proposed total cost exceeds the funds available, the proposal is rejected.

4. All proposals become the property of the Transportation Research Board. Final disposition will be made according to the policies thereof, including the right to reject all proposals.

5. Potential proposers should understand that follow-on activities for this project may be carried out through either a contract amendment modifying the scope of work with additional time and funds, or through a new contract (via sole source, full, or restrictive competition).

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