Mitigating Existing Floor Vibration Issues in a School Renovation

Abstract

For over 40 years, students, faculty, and staff have been living with an often disturbing level of floor vibration caused by pedestrian traffic in an open plan library area of a suburban middle school. The library extends just beyond a 47 × 52 ft bay framed with a 3 in. slab on metal deck supported by 28 in deep steel joists spanning the short direction and W36 rolled girders in the long direction. As part of an upcoming major renovation, there is interest in exploring cost effective alternatives to reducing the impact of the current conditions. To quantify and understand the existing behavior and make suggestions to alter the behavior, a research study was undertaken. This paper describes the vibration measurements taken, assesses the behavior found including the surprising impact of higher order modes, and explores possible options to mitigate the impact of vibration on the occupants.