In response to local expectations and the traveling public, there is a national need for aesthetic improvement of typical highway features. Requests for barrier treatments and bridge rails that contribute to the overall aesthetic experience are increasing. Research will assist owners in responding to design requests for aesthetic improvements to transportation systems.
Concrete barriers (e.g., New Jersey and F-shapes and single slope and vertical face designs) are often the barriers of choice in urban and suburban environments. Many agencies and communities have expressed a desire for aesthetic treatments for these standard shapes. To date, there has been limited evaluation to determine which aesthetic treatments are safe and practical. Current standards do not provide guidelines to improve the appearance of the concrete barrier.
Local communities and agencies are also demanding increasingly that state DOTs provide bridge rails with an enhanced "see-through" appearance. Existing designs do not fully meet the desire of the public for a see-through appearance. However, the use of innovative designs and materials may result in the development of aesthetic bridge rails with improved view spaces.
Designers need guidelines for aesthetic treatments of concrete barriers and additional options for see-through bridge rails.
The objectives of this research are to (1) assemble a collection of examples of longitudinal traffic barriers exhibiting aesthetic characteristics, (2) develop design guidelines for aesthetic concrete roadway barriers, and (3) develop specific designs for "see-through" bridge rails.
Accomplishment of the project objectives will require at least the following tasks. (1
.) Identify the features and methods that contribute to the aesthetics of longitudinal traffic barriers and the aesthetic experience provided by the roadway. (2.
) Conduct a literature search and survey of U.S. and foreign sources for examples of aesthetic longitudinal traffic barriers. The survey shall also identify desired aesthetic treatments for existing concrete barrier shapes and identify new see-through bridge rail designs. The purpose of this task is two-fold: (1) to satisfy the first project objective and (2) to identify a range of treatments and designs for further evaluation in Task 7. (3
.) Review existing test results and ongoing research to assess the crash worthiness of the aesthetic concrete barriers and see-through bridge rails identified in Task 2. (4.
) Develop an evaluation plan based on the findings of Tasks 1, 2, and 3. The evaluation plan shall include, as a minimum, the following: a) concrete barriers -- based on the range of treatments identified, develop an evaluation plan that may include visualizations, crash test validation, and other methods necessary to define the parameters that will ensure the successful performance of specific aesthetic treatments for concrete barriers. b) see-through bridge rail -- based on the designs identified, develop an evaluation plan that may include visualizations, crash test validation, and other methods necessary to develop design details for new "see-through" bridge rails. The evaluation plan should also include a discussion of bridge rail transitions. (5.
) Submit an interim report documenting the findings of Tasks 1 through 3 and the Task 4 evaluation plan. The summary of the literature search and the survey shall include, as a minimum, the following for selected examples of aesthetic longitudinal traffic barriers:
Design drawings and photographs,Summary of crash tests and results,Initial cost, Application, andContact information.
(6.) Meet in Washington, D.C. with the NCHRP panel to review the Task 5 interim report, including the evaluation plan, approximately 1 month after its submittal. Submit a revised interim report reflecting the panel's review comments. (7.) Execute the approved evaluation plan. (8.) Develop the guidelines and specific designs based on the findings from Task 7. (9.) Submit the final report documenting the entire research effort. The final report shall describe how the project was conducted and include as appendices the guidelines for aesthetic concrete barriers and the designs for new see-through bridge rails.
Status: The project has been completed and the final report published.
Product Availability: NCHRP Report 554: Aesthetic Concrete Barrier Design