PSI - Issue 70

Aamir Anwar Nezami et al. / Procedia Structural Integrity 70 (2025) 105–112

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Fig. 3: Effect of thickness on the critical buckling loads of (3a, 3b) anti-symmetric cross-ply laminates with two and eight layers, and (3c, 3d) anti-symmetric angle-ply laminates with two and eight layers, respectively, under uniaxial compression.

4. Results and Discussions For nine-layer symmetric cross-ply laminated composite plates, in Fig. 1 and 1 the results obtained from Exact3D elasticity solutions for various length to thickness ratio of plates are shown and compared with CLPT. It can be seen that the CLPT results match with Exact3D solutions only for very thin plates (a/h=100). In Fig. 1 – 1 , various theories are compared and it can be seen that the results for displacements and stresses closely match with present zigzag theory while FSDT and Sorrenti’s zigza g theory yields slightly deteriorated and stiffened results. For five-layer symmetric angle-ply sandwich plates, the results are presented in Fig. 2. The displacement and stress distributions in Fig. 2a – 2d demonstrate that both the Present model and Sorrenti’s model closely match the Exact 3D solutions, whereas the Murakami Zigzag model exhibits significant deviations. This discrepancy arises because the Murakami Zigzag theory relies solely on geometric parameters and neglects material property dependencies, leading to inaccuracies in modelling sandwich plate behaviour. Figure 3a – 3d presents the buckling behaviour of plates with varying layer counts and stacking sequences. A comparison of different theories reveals thatClassical Laminate Plate Theory (CLPT)overestimates buckling loads for thick plates but provides satisfactory results for thin plates. Specifically, fortwo-layer