Nonlinear finite element analysis on timber-concrete composite beams

To support the parametric analysis of timber-concrete composite (TCC) beams and the structural analysis of TCC frame systems, the computational effectiveness of various dimensional finite element (FE) models for TCC beams were evaluated in this study, including the one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D). It was found that the 1D frame FE model achieved by the fibre beam elements and the 2D model formed by the layered shell elements show apparently higher computational efficiency than the 3D FE model with solid elements. The FE models all exhibit good consistence with the test results in terms of the macroscopic bending performance of the TCC beams. Owe to the developing of the ABAQUS user subroutines in this study, the 3D model established in the ABAQUS/Explicit module could almost perfectly present the failure modes of the TCC beams, including the fracture of timber, failure of end connections, and cracks on concrete slab, and show higher accuracy of the numerical results than the 1D and 2D models. Additionally, the FE numerical interfacial strain and slip distributions are slightly larger than the test ones, due to various shortcomings of the definitions of the connections in the FE models. Generally, the FE models were validated to be feasible sufficiently for further studies on TCC structures.