Dover Tests New Crosswalk Application

The city of Dover recently installed a new crosswalk, with a new material. It is a modified asphalt compound of graded sand and granite aggregate and reinforced with two types of fibers. Dover is the first community in NH to test the new crosswalk, and only one of ten in the US .

The process, developed in the United Kingdom 15 years ago, is used in traffic areas with 80,000 Average Daily Traffic (ADT) in London . The mate­rial does not abrade and reportedly lasts about twenty years. The Dover crosswalk, at 366 Central Ave, should see an ADT of less than 10,000.

Twelve standard colors are available and cus­tom colors are possible. The color is part of the mixture so it will not wear off. The product compo­sition allows for a skid resistance value of more than 60. The ASTM E274 specifications describes skid numbers of 30 and above as acceptable for low-volume roads and 35-38 as acceptable for heavily traveled roads.

The crosswalk installation begins with grinding down the existing crosswalk. The area is prepared by sweeping and the material is heated to 437℉. It is placed by hand and “ironed.” The ironing gives the finished effect a “heritage” look as it is not exactly level like asphalt texturizing. After the material smooth, it is imprinted. The material cannot be put down in lifts greater than 1 inch as it will begin to crack. The road can be opened to traffic in 30-45 minutes.

The City of Burlington, Vermont, installed two crosswalks two years ago. The first was quite mild but last year was not. Dan Bradley, of the Public Works Department, is very please with the products performance.

Other applications for the imprinting process include sidewalks, median strips and traffic calming devices such as speed tables. Readers should contact the UNH T² Center or the City of Dover for more information

Source:

http://www.usroads.com/journals/rej/9706/re970603.htm  

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