Seismic performance of cold-formed steel framed houses

For the proper design of cold-formed steel-framed houses in earthquake regions, the behavior of the shear walls has to be known. Besides the structural walls the behavior of a house is influenced, at least in the early stage of the shaking, by the non-structural elements which are not accounted in the design. These supplementary finishing elements change the periods of vibration and the damping properties of the structure, but may also change the vibration shape. In this study the vibration properties of a steel framed house are studied using Finite Element (FE) modeling and direct measurements on the structure. The main modal characteristics are determined in three stages of construction and are compared to each other in order to evaluate the influence of the non-structural elements which are not accounted in the modeling. The main conclusion is that non-structural elements have important influence on the rigidity of the structure.