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This paper reports a series of component tests on a lightweight floor system and a method to predict the natural frequency of the floor using a frame analysis program. Full-scale floor tests are also briefly described. DuraGal steel Rectangular Hollow Sections (in-line galvanised RHS) are used as joists, bearers and piers in DuraGal lightweight floor systems. A structural grade particleboard is used as decking. Connection stiffness between different components (bearer, joist, pier and floor decking) was determined. A 40% composite action was achieved between the RHS joist and the particleboard. Both 2D and 3D models were developed to study the effect of connection stiffness on predicting the natural frequency of DuraGal lightweight floor systems. It has been found that the degree of shear connection between the bearer and the joist has a significant influence on the floor natural frequency. The predicted natural frequencies are compared with measured values from full scale floor testing. more...

Publisher Summary This chapter investigates the dynamic performance of steel lightweight floors. Cold-formed square hollow sections and rectangular hollow sections are used as piers, bearers, and joists. The dynamic performance of a floor at three different stages of construction is determined. The three stages are a standalone floor; a floor with wall frames and ceiling; and a floor with wall frames, ceiling, and roof loading. Three types of tests are performed at each stage: dynamic tests to determine natural frequencies, damping, and vibration modes; static tests to measure maximum deflection of the floor; and subjective tests to obtain human response to vibration. The tests demonstrate the change in the dynamic parameters, the maximum deflection, and the human response at different stages. The static deflection test shows no change in the deflection under 1 kN concentrated load. The damping for the first mode increases from 3.2% to 6.6%, and a similar increase for other modes is observed, as well. This could be explained by the absorption of some of the vibration energy by the wall and ceilings. The roof loading changes the first natural frequency and damping, and correspondingly there is change in the mean of human acceptability. more...