Vibration Evaluation of Lightweight Floors Supported by Cold Formed Steel Joists

Abstract

Lightweight floors supported by cold formed C-shape steel joists have become increasingly popular in residential construction in North America in recent years. Compared to the traditional wood floor systems, floors supported by cold-formed steel joists are usually lighter and can provide an economical solution for longer floor spans, which are often desired by both homeowners and architects in creating the so-called open concept design. Therefore, like other lightweight floor systems, steel-framed floor systems may become vulnerable to human-induced floor vibrations if the associated dynamical behavior is not appropriately addressed in the design of such floor systems. The chapter carries out static and dynamic tests on floor systems, where static tests are conducted to evaluate the stiffness and load-sharing capacity among the joists, while the dynamic tests are conducted to evaluate relevant dynamic characteristics, such as natural frequencies and damping ratios of the floor systems. The test results are then compared with those obtained from different analytical methods, and an analytical method is proposed to evaluate the performance of lightweight residential floors supported by cold-formed steel joists.