In-situ measurement of material properties of gypsum board walls

The dynamic behaviour of lightweight framed gypsum board walls is very complicated due to its frequency dependency. Basically, it is determined by the material properties of the struc-tural members – the gypsum board and the studs – and the way of their assembly. In a test series the dynamic response of the leaf of different gypsum board walls is investi-gated and the wave numbers of free bending waves are measured in-situ. From the bending wave numbers it is possible to estimate the frequency dependent stiffness properties of the structure. The test walls are geometrically almost identical, but differ in their structural details, like for instance the stud spacing and the number of layers of gypsum board. Since the stiffness prop-erties of the used materials are known, respectively are also determined experimentally, it is possible to compare them with the measured properties of the leafs of the walls and define frequency ranges where structural members participate differently in the dynamic response of the leaf. The obtained results are very useful for the understanding of the dynamics of lightweight framed structures and can further be used for modeling or predicting the dynamic response, sound radiation, etc of gypsum board walls.