Cyclic behavior of screw connections in plasterboard partitions

The paper reports the results of an experimental campaign aimed at characterizing the hysteretic behavior of screw connections of cold-formed framed plasterboard partitions. Cyclic quasi-static tests are carried out under displacement-control considering seventeen connection types, representative of plasterboard partitions’ connections between panels and internal cold formed studs. The experimental campaign consists of about eighty tests, with specimens tested in multiple arrangements and considering three testing configurations. The cyclic behavior of the specimens is analyzed in terms of maximum strength, corresponding displacement, secant stiffness, and energy dissipation. A description of the occurred damage and the failure modes, recurring in the three testing configurations, is also reported. The influence of key parameters, like test configuration, screw connection type, board thickness, number of board layers, and stud cross section width, on the hysteretic behavior of the tested connections is quantitatively assessed. The results are also statistically assessed by means of fitting cumulative distribution functions (CDFs) assuming a lognormal model. Energy dissipation and secant stiffness degradation models are finally provided. The presented quantitative data and correlations represent the basis for robust expeditious estimation purposes and for experimental calibration of advanced numerical models of plasterboard partition screw connections.