Experimental testing and finite element analysis of the tensile response of toothed flange connections

Modern steel erection relies on two main connection methods, welding and bolting, which can be expensive field activities and have remained unchanged for nearly a century. To achieve savings in both weight and cost, increased construction effectiveness and higher steel reuse, a novel type of toothed steel connections with the use of precise, advanced manufacturing methods in waterjet or laser cutting has been established that is based on an interlocking approach to connect steel components that have exactly cut ends. This paper presents testing and finite element analysis (FEA) studies of three unique flange plate geometries of the toothed steel connections failing in tension. Tensile tests were carried out on six samples of the toothed flange connections for each of the three geometries and the digital image correlation (DIC) method was utilized to attain axial displacement. The observed key test results, including load—displacement responses, yield loads, failure loads and modes, were fully presented. Strain contours of the connection geometries with the use of the DIC technique at early stage loading and near ultimate failure were also presented. The experimental program was accompanied with a numerical modeling program, in which finite element models were first created in Abaqus structural analysis software and compared against the test results. Based on the tests and numerical data, the performance and the capacity of the three unique flange connections were assessed. The FEA results agreed very well with the test results, indicating that the numerical simulations can accurately predict yield, ultimate load capacities and failure modes of the toothed connections. The numerical models characterized thoroughly the predicted stress distributions within the connections. For capacity-based design, the second flange connection (CON2) geometry could be adopted in beam tensile zones due to its better overall performance.