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5 Figure 2. Typical steel rails used by state DOTs. Public requests for aesthetic barriers and rails are very that the most commonly used barrier is the safety shape common in the states. Forty-six percent of states said that design. they get a lot of requests from the public for more aestheti- A large number of photographs were received from around cally pleasing roadside structures. Figure 3 depicts the pub- the country. An insight into concepts that are being experi- lic requests. mented with can be gained from a review of these photo- Only 27% of states said that they use see-through bridge graphs. A few of these that demonstrate the range of ideas in rail designs. Thirty-two percent incorporate colors into their current usage are shown in Figure 4. concrete barriers, and 24% have used veneer products, such as precast imitation stone or brick, on their concrete barriers. SURVEY OF U.S. AND INTERNATIONAL Sandblasted patterning on concrete barriers is not a widely CRASH TEST LABORATORIES used practice, with only 7% of states using this aesthetic treatment. U.S. Crash Test Laboratories Eighty-eight percent of states do not conduct any testing on their barriers or rails, and only 41% stated that they would Out of 12 surveys sent via e-mail to U.S. crash test labora- like to see testing performed on specific designs. tories, 11 responses were received. Of these, 82% stated that Most state DOTs are getting increased requests for aes- they have not done any work in the area of aesthetic barrier thetic roadway structures. Some are starting to develop their design and/or testing and 18% provided information for use own guidelines for their designers, but most are relying on on this project. existing examples that have proven reliable in other states. California DOT (Caltrans) and Midwest Roadside Safety There were some comments from respondents to the effect Facility (MwRSF) were the two U.S. labs that provided that the only good rail is a smooth rail and that aesthetics information as part of the survey. Caltrans provided crash should in no way compromise it. This sentiment occurred test reports, 16-mm film, and videos for analysis of their in a very small number of responses, but may be common research effort to develop design guidelines for single-slope among designers in some states. This is reflected in the fact and vertical-face concrete barriers. MwRSF provided crash test reports of aesthetic concrete barriers and steel rails. International Crash Test Laboratories Out of 18 surveys sent via e-mail to international crash test laboratories, 12 responses were received. Of these, 33% stated that they could not provide information due to confi- dentiality issues, 42% have not done any work in this area, and 25% provided information on aesthetic barriers. The labs that provided information were Autostrade, Italy; Transport Research Laboratory (TRL), United Kingdom; and Swedish National Road and Transportation Research Institute (VTI), Figure 3. Public requests for aesthetic barriers and rails. Sweden.

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6 Photographs provided by Autostrade are shown in Fig- smooth concrete finish of natural color. The majority of ures 5 and 6. Both installations are types of safety shape con- all bridge rails take the form of vertical posts with hori- crete barriers. The first, shown in Figure 5, is used in Rome zontal rail members, deeming them see-through. Photo- near the Aurealian ancient walls of the city. In actual appli- graphs of several see-through bridge rails are shown in cation, flowers and plants are planted in the upper part of the Figure 8. barrier. The second installation, shown in Figure 6, is a vari- VTI is the only international test laboratory to submit ation of a New Jersey border bridge, which allows motorists results of NCHRP Report 350 testing done at their facility. to view the landscape. The GPLINK concrete road barrier, manufactured by Gun- TRL also provided photographs of concrete barriers nar Prefab AB in Mora, Sweden, has FHWA approval for and see-through longitudinal bridge rails. Figure 7 depicts Test Level 3. The FHWA acceptance letter can be accessed several types of concrete barriers currently used on the at http://safety.fhwa.dot.gov/roadway_dept/road_hardware/ United Kingdom Highways Agency (HA) roads. All con- barriers/pdf/b-62.pdf. Photographs of the GPLINK concrete crete safety barriers used on the HA network have a plain, barrier are shown in Figure 9. Figure 4. State DOT photographs.

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7 Figure 4. (Continued ).

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8 Figure 4. (Continued ).

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9 Figure 4. (Continued ).

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10 Figure 4. (Continued ).

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11 Figure 4. (Continued ).

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12 Figure 4. (Continued ).

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13 Figure 5. New Jersey barrier used in Rome. Figure 6. New Jersey border bridge used in Italy.

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14 Figure 7. Concrete barriers used in the United Kingdom. Figure 8. See-through bridge rails used in the United Kingdom.

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15 Figure 9. GPLINK concrete barrier.