Vibration Testing of a Floor During Multiple Phases of Construction

Abstract

It is often difficult to conduct modal testing and response measurements during the construction of civil structures. This is a result of both the time requirements and accessibility, both of which limit the opportunities available for testing. Clean measurement data can sometimes be difficult to obtain due to disturbances on site from other construction activities. This paper presents the results from a unique opportunity to conduct full modal tests on a lightweight office floor during renovation for adaptive re-use. Originally a warehouse facility, the building renovation involved adaptation to executive office spaces. This included renovation of a lightweight mezzanine floor area that would house senior management staff. The author was provided the opportunity to measure the floor in a bare (unfinished) state, followed by partial and complete fit-out conditions. Footfall response measurements were conducted along two distinct walking paths during each phase so that the variations in floor response could be quantified at key locations. The modal and footfall response tests were correlated to finite element models of the floor for evaluation of finite element and footfall force modeling techniques. The results from the study provided insight on finite element modeling techniques and the effects of finishes and other non-structural elements on the dynamic characteristics of the floor.