Evaluation of the Tilt and Absorbing Noise Barriers on I-78 Sections 5M, 5BW, and5BY in Union County, NJ

摘要

In 1986 New Jersey completed an eight-mile section of I-78 in Union County, whichincluded the construction of two innovative traffic noise barriers. Both barriers were concrete and post-and-panel structures, designed ostensibly to reduce the assumed interaction between parallel barriers which was considered to degrade barrier effectiveness. One barrier was tilted 10 degrees away from the roadway and had a standard hard concrete grapestake finish, the opposite barrier being of the same type. The second type of barrier was vertical and the panels were covered with a proprietary absorbing finish. Some of the opposite barriers had the same finish, while others had a non-absorbing finish. Both innovative barriers were evaluated for their effectiveness in reducing farside noise levels and increasing nearside insertion loss vis-a-vis a standard barrier with a reflective finish. This evaluation was carried out in two phases.