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(2022)ThesisFibre reinforced laminated composites offer many benefits over conventional materials and hence are now used in most engineering sectors. However, their intrinsic in-homogeneity and anisotropic properties make modelling damage initiation and propagation a challenging task. This thesis explores a relatively new semi-analytical approach, Scaled Boundary Finite Element Method (SBFEM), for accurate and efficient modelling of inter-ply damage in thick laminated composites, which is sometimes referred to as interfacial imperfection, debonding or delamination. SBFEM is a tool which combines the benefit of finite element method (FEM) and boundary element method (BEM). In SBFEM, boundaries are solved numerically, whereas an analytical solution is obtained inside the domain. This considerably reduces the computational effort required to solve the problem. In its framework, a 2D plane strain approach is first considered to model the laminated composite plates undergoing cylindrical bending. The work is then extended for 3D modelling to model the bi-axial bending of plates. Unlike 2D plate models, these approaches do not make any assumption on the displacement field and hence, provides superior results. Modelling has been performed in perfectly bonded conditions as well as with interfacial imperfections. Often thick laminates make up the load bearing components of engineering structures; however, they are challenging to model accurately, particularly in cases where out-of-plane loads are significant. Thus, the applicability of the presented modelling technique using SBFEM is assessed over traditional numerical approaches for modelling thick laminated composites. The model is then expanded to study progressive delamination growth using cohesive zone modelling, in pure as well as mixed mode fracture conditions. Finally, for experimental validation of the SBFEM predictions and to justify the application of theoretical approach in practical scenarios, in-house experimentations performed for the fracture studies are modelled. The SBFEM approach for analysis of inter-ply damage in laminated composites is found to be in good agreement with traditional methods while achieving significant reduction in the computational cost. Precise behaviour of laminates can be captured without the necessity of multiple sub-divisions in the throughthickness direction of plies. Moreover, the requirement of having small interface elements can be fulfilled without refining the mesh in the adjoining regions. In this way, SBFEM reduces the computational cost of the model many folds without any compromise in the accuracy. The thesis provides a basis for future research on the application of SBFEM to model inter and intra-ply damage in complex laminated composite structures.