Sensitivity Analysis of a CPAM Inverse Algorithm for Composite Laminates Characterization

Using experimental data and numerical simulations, a new combined technique is presented for characterization of thin and thick orthotropic composite laminates. Four or five elastic constants, as well as ply orientation angles, are considered as the unknown parameters. The material characterization is first examined for isotropic plates under different boundary conditions to evaluate the method’s accuracy. The proposed algorithm, so-called CPAM (Combined Programs of ABAQUS and MATLAB), utilizes an optimization procedure and makes simultaneous use of vibration test data together with their corresponding numerical solutions. The numerical solutions are based on a commercial finite element package for efficiently identifying the material properties. An inverse method based on particle swarm optimization algorithm is further provided using MATLAB software. The error function to be minimized is the sum of squared differences between experimental and simulated data of eigenfrequencies. To evaluate the robustness of the model’s results in the presence of uncertainty and unwanted noises, a sensitivity analysis that employs Gaussian disorder model is directly applied to the measured frequencies. The results with high accuracy confirm the validity and capability of the present method in simultaneous determination of mechanical constants and fiber orientation angles of composite laminates as compared to prior methods

Effect of Nanoclay Filler on Fatigue Life of Natural Rubber/Styrene-Butadiene Blend

In this paper, the fatigue life of natural rubber (NR)/styrene-butadiene rubber (SBR) compound is evaluated experimentally. The parameters investigated are the NR, SBR, and nanoclay loading in the composition, strain amplitude, and the frequency of the fatigue test. Fracture surfaces of NR/SBR/nanoclay compound are investigated using scanning electron microscopy (SEM). The results show that by increasing NR and the nanoclay loading in the rubber composition, the fatigue life of the rubber increases. For the nanoclay, a threshold value exists beyond which the fatigue life of the rubber compound decreases. It is also observed that by increasing the test frequency, the fatigue life of the rubber compound decreased. Tensile, hardness, and dynamic mechanical thermal analysis (DMTA) tests were also performed to evaluate the mechanical and thermal properties of the compound. SEM results show that by increasing the strain amplitude, the test specimens fail softly, and the addition of nanoparticles roughens the fracture surface and increases the fatigue life

sj-docx-3-pie-10.1177_09544089231217977 - Supplemental material for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method

Supplemental material, sj-docx-3-pie-10.1177_09544089231217977 for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method by Mojtaba Aghamirzaie, Ahmad Ghasemi-Ghalebahman and Amir Najibi in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p

sj-docx-5-pie-10.1177_09544089231217977 - Supplemental material for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method

Supplemental material, sj-docx-5-pie-10.1177_09544089231217977 for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method by Mojtaba Aghamirzaie, Ahmad Ghasemi-Ghalebahman and Amir Najibi in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p

sj-docx-6-pie-10.1177_09544089231217977 - Supplemental material for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method

Supplemental material, sj-docx-6-pie-10.1177_09544089231217977 for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method by Mojtaba Aghamirzaie, Ahmad Ghasemi-Ghalebahman and Amir Najibi in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p

sj-docx-7-pie-10.1177_09544089231217977 - Supplemental material for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method

Supplemental material, sj-docx-7-pie-10.1177_09544089231217977 for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method by Mojtaba Aghamirzaie, Ahmad Ghasemi-Ghalebahman and Amir Najibi in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p

sj-docx-1-pie-10.1177_09544089231217977 - Supplemental material for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method

Supplemental material, sj-docx-1-pie-10.1177_09544089231217977 for Optimization of the octagonal origami tube energy absorption using the artificial neural network and heuristic method by Mojtaba Aghamirzaie, Ahmad Ghasemi-Ghalebahman and Amir Najibi in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p