Edinburgh Napier University

  Excessive vertical vibration of lightweight floors caused by walking or similar activities can be annoying to building occupants. Previous studies have shown that the vibrational performance of floors having wood joists is enhanced by installing one or more lines of bridging elements that form transverse spines in the across-span direction. This paper presents an experimental study that defined relationships between the effective flexural rigidity of such spines and response characteristics of wood joisted floors. Behaviors of spines having both normal and special types of bridging elements were investigated, with the special types of elements able to create a broad range of spine flexural rigidities. It was found that all types of transverse bridging spines have a small influence on fundamental natural frequency but can increase higher order modal frequencies considerably. Relatively stiff types of transverse bridging spines reduced static deflections caused by concentrated gravity forces considerably. An experimental method is presented for quantifying effective flexural rigidities of transverse bridging spines. Suggestions are made concerning application of the research findings in vibration serviceability design of lightweight wood joisted floors.