Ground-borne vibration issues from rail transit near university research buildings

Abstract

A new light rail transit project being designed and constructed through a university campus presents many potential ground-borne vibration issues. The rail alignment passes near numerous buildings on campus that contain various types of vibration sensitive research equipment. Appropriate vibration criteria for the project are critical to ensure that future operation of the light rail vehicles (LRVs) will not adversely affect activities on campus. Ground-borne vibration criteria are based on equipment sensitivity and the existing vibration environment. Projections of future vibration levels from LRV operations were developed based on field measurement programs. Site specific vibration measurements on campus were conducted to document the soil vibration propagation characteristics and building response characteristics. Additionally, input vibration force characteristics, or vehicle force density levels, of a comparable vehicle were measured and incorporated into the projections. Finally, site specific track design and vibration mitigation measures were modeled and incorporated into the project design.