Stress-strain behavior of plasterboards subjected in tension and in compression

Plasterboard components are widely used in current buildings worldwide. Pl asterboards are employed for partitions, wall lining and ceilings. Plasterboards are used for both structural and nonstructural walls. Mechanical properties, e.g. modulus of elasticity or tensile/compressive strength, of plasterboards may assume a key role in the whole seismic performance of a building. Numerical models of building components which include plasterboard elements, such as internal partitions, require the definition of the mechanical properties of plasterboards. Despite their extensive use, th e lack of a comprehensive test campaign on plasterboards in the current literature is denoted. An extensive test campaign, consisting of 302 tests, is therefore performed aiming at evaluating compression and tension behavior of plasterboards. A set of fiv e plasterboard typologies is selected, considering different board thicknesses and both standard and high- density boards. Both tensile and compression tests are performed according to EN 789. The tests are performed in two different load directions, i.e. p arallel or transversal to the direction of production. Tensile strength of boards is systematically smaller than compressive strength, whereas elastic modulus values in compression and in tension are similar. Regression laws that can be employed to model b oth compression and tension behavior of plasterboards are defined for future implementations of the actual stress -strain relationships in different applications, e.g. FEM analysis of shear stud wall panels. A bilinear stress -strain envelope is adopted for tensile behavior, whereas a model typically used for concrete is selected for compression behavior. An orthotropic behavior is exhibited in case the boards are loaded in tension. The significant influence of board thickness on their mechanical properties i s also highlighted. T he most appropriate probability distribution function is estimated for several mechanical parameters and the corresponding data dispersion is evaluated. The uncertainty associated to each of the four selected parameters is therefore ev aluated considering the corresponding lognormal distribution functions. The dispersion of the data around the median value is significantly influenced by the considered mechanical parameter. In particular, elastic modulus in tension is characterized by a l arge uncertainty, i.e. β values up to 0.68. Both tensile and compressive strengths show small variability around the mean. Finally, the uncertainty is influenced neither by the direction of loading nor by the thickness of the boards. The performed activiti es can be used as reference for future numerical studies involving plasterboards .