Finite element modelling of timber-steel screw connections

Abstract

This dissertation delves into the timber-to-steel and steel-to-timber composite system, whereby plywood panels are combined with cold-formed profiled steel decking by means of self-drilling screws, providing a finite element model validated with the load-slip response from push-out testing conducted on specimens in a previous investigation of this system. ABAQUS™ finite element software was used for the scope of this study. An iterative method of assessment was adopted, in addition to consulting similar research, whereby the different options provided by this program are investigated to develop a model which best simulates the behaviour of the individual components interacting with each other in the critical connection region. Results from the output of analyses performed are presented and discussed in relation to the behaviour exhibited by the model and efficiency of computation. Data for material properties was extracted from tests carried out in Grech [3], to assess the behaviour of each constituent component of the system under study. Relevant literature has indicated the need to develop analytical models which provide information on the behaviour of timber connections prior to failure. This model intends to furnish the designer with a tool to assess the load-slip response of the system's connection in stages along the loading process, supplementing physical testing, in the hope of promoting its use over traditional flooring systems. Validation of the model extends to a comparison of the deformation exhibited in the connection region with illustrations documented from physical push-out tests. Sufficient agreement was achieved from resulting data and visual assessment.