Assessment of Floor Vibrations for Building Re-use: A Case Study

Abstract

Developments involving building re-use can present numerous challenges with respect to evaluation of structural floor capacity and establishing controls for serviceability. Retrofit strategies can be particularly challenging when engineering drawings of the structure are scant, or even non-existent. This paper presents a case study involving renovation of a light-weight mezzanine warehouse floor into executive office space. During early construction the floor was observed to be particularly lively, attributable to its lightweight, long-span construction and lack of non-structural elements. The author was engaged by the client to assess the floor and evaluate expected performance following fit-out. This included field measurements of frequency response and footfall vibrations, development of a computer model and correlation of the model with the field data. Simulations were conducted to validate random force models presented in the literature. The force and response models were then employed to assess expected performance of the floor. All modeling was conducted in the absence of engineering drawings, providing valued lessons on FEM techniques for floor systems. Measurements were also conducted following partial fit-out to track the change in the floor’s dynamics and footfall responses.