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Purpose of this study is to obtain failure modes and failure loads of two Parallel pin loaded holes in unidirectional glass fibre/epoxy by adding nanoclay in the absence of nanoclay composite laminates using finite element analysis; the results are validated through experiment. The geometrical parameters studies in this survey include the distance between the diameter of the hole (e/d) and the free edge of specimen, the distance between two holes-to-hole diameter (M/d). The samples were exposed to constant speed tensile loading. The results showed that by adding nanoclay, failure load increases and failure modes varies from shear out to bearing failure. Furthermore, increasing distance from the free edge of the pin centre's increases load bearing capacity of two type of composite materials and changes the failure mode from shear to the bear, it increases and decreases the distance from canter's of pin in layers with and without nanoclay particles, respectively and changes failure mode from shear to bear mode. In order to find morphology of specimens and dispersion quality, Scanning Electron Microscope (SEM) was used. For predicting failure load and differentiating failure modes, Tsai-hill failure criteria associated with material property degradation is used. Experimental and FEM results indicate importance of considering the impact of e/d and M/d ratios in the design of two Parallel pin joints. ANSYS was used to carry out numerical simulation and the results denote a good agreement between numerical and experimental results. In this study, by designing an experimental and numerical procedure to estimate the effect of nanoclay, on failure mode and failure load of typical composite material, glass-epoxy, we could illustrate that adding nanoclay brought with it improvement of shear and tensional strength of glass-epoxy about 10%. [ABSTRACT FROM AUTHOR]

Performed was a set of experimental tests to scrutinize the effect of the welding angle and material properties on the spring-back and the displacement as well as the amount of required load in the standard bending test according to ASTM B820- 18 with some numerical simulation conducting to compare those results and calculate stress through the bending process. The applied sheets were made of Copper, Aluminum and St12, DIN1623 with a thickness of 1 mm. In this study, prepared is a welding line at three angles, 30°, 45° and 90° whilst two punch's radiuses have been considered. Additionally, three orientations 0°, 45° and 90° have been considered to check the homogeneity of the plate. Added to this, a numerical analysis utilizing finite element methods was conducted to validate the results obtained from the experimental tests. based on results, there wasn't seen any considerable difference (less than 10 %) in terms of un-homogeneity in results while the minimum springback pressure for the St12-Cu sheet was equal to 3.6, and measured 3.70 for St12-Al. In the numerical solution, the maximum stress for the welding angle, 30, in St12-Al sheet was 305 MPa with the springback decreasing from 0.1 to 0.5 whenever the pitch radius changing from 5 to 10 mm. [ABSTRACT FROM AUTHOR]

The aim of this study is to scrutinize the effect of nano-additions on failure modes and loads of glass-epoxy laminate subjected two parallel pin-loaded holes, experimentally and numerically. Furthermore, the effect of physical and geometrical parameters such as the ratio of free edge distance of laminated composite to holes diameter (e/d) and the ratio of centre to centre distances of holes to holes diameter (M/d) have been investigated. Afterwards, to exactly prognosticate failure modes and the ultimate load obtained from the experimental procedure, a numerical simulation in finite element software was implemented. There have found a close agreement between two methods. It should be acknowledged that after augmenting glass-epoxy laminate with nano-addition A12O3, there was seen to be a clear difference between the two samples while the bearing strength of reinforced samples has been improved. [ABSTRACT FROM AUTHOR]

This paper develops the scaled boundary finite element method to analyse fracture of functionally graded magneto-electro-elastic materials. Polygon meshes are employed to discretize the domain. No asymptotic solution, local mesh refinement or other special treatments around a crack tip are required to calculate the intensity factors. When the material gradients of the coefficients in the constitutive matrix are expressed as a series of power functions of the scaled boundary coordinates, the stiffness matrices can be integrated analytically. The formulation enables the generalized intensity factors of stress, electric displacement and magnetic induction fields along the radial direction to be represented analytically. This permits the calculation of the generalized intensity factors directly from the scaled boundary finite element solution of the singular stress, electric displacement and magnetic induction fields by following the standard stress recovery procedures in the finite element method. Several numerical benchmarks are presented to validate the proposed technique with the results reported in the literature. • The SBFEM was developed for functionally graded magneto-electro-elastic media. • Flexible discretization using polygons with an arbitrary number of sides. • Crack tip is modelled using a single polygon. • Semi-analytical modelling of heterogeneity in polygons with local least-squares fit. • Direct calculation of intensity factors from semi-analytical solutions of stress. [ABSTRACT FROM AUTHOR]