Problem Statement
Vibration propagation through the ground is physically very similar to the propagation of noise through the air. Vibration and noise are similar in other respects as well; however, the criteria by which scientists judge the acceptability of noise and vibration are quite different. For example, environmental noise is typically judged on the basis of cumulative noise exposure using the DNL metric. The DNL is essentially a 24-h average with a 10-dB nighttime penalty to account for people’s increased sensitivity to noise at night. The well-known “Schultz” curve is a dose-response relationship between airborne sound levels and the percentage of people highly annoyed. This curve forms the basis for the expected change in noise impact due to either increasing noise level or the frequency of occurrence and duration of noise events. However, the vibration impacts of transportation projects are assessed solely on the basis of maximum vibration level and do not generally take into account the frequency of occurrence of the events. Attitudinal surveys for vibration effects, similar to surveys used in the Schultz curve development, would be required to develop such a vibration dose-response curve.
 
Proposed ResearchDevelop a dose-response curve for vibration and ground-borne noise to assess the change in annoyance due to change in the frequency of occurrence and duration of vibration events.