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Disparate industry bodies across the planet use pallets for storing large and heavy objects. Pallets provide an assurance of safe handling of material (cargo) and storage of material in a damage-free environment. In this work, an attempt has been made to analyze and investigate making pallets out of ULTEM 9805 using the latest additive techniques (FDM). The maximum deflections and von Mises stresses are analyzed for the disparate boundary conditions indicating the possible alternatives or loads to be used. Study of surface (morphology) and characteristics was done in order to establish the relationship between pallet surface and its application. The factors of load, maximum and minimum values, ascertained in each stage are 168.15, 522.22, 215.31 and 316.79 kPa as well as 18.77, 6.7, 1.2 and 35.84 kPa for the floor, rack, forklift and conveyor load supports, respectively. A cross-hatched design causes a rise in capacity of the shear factor owing to the length of the span being in correlation with rectilinear fill. The filament of surface, made of ULTEM 9805, exhibits a level of roughness of 43.14 μm on the pallet surface indicating better holding capacity and grip. A 9^∘ peak shift is comprehended with respect to XRD, indicating a compressive residual factor measured at 76.47 MPa.

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Intentional buckling as a fabrication technique for arch frameworks results in prestrains at every section of the arch, which in turn affect its strength and stability. A nonlinear corotational straight beam element with elastic, linear strain hardening material has been developed to study the elasto-plastic buckling of prestressed arches. The study indicates that for prestressed arches there is an interdependence between the slenderness and steepness ratios of the arch with the ratio of prestresses to the yield strength of the material, all of which control the magnitude and shape of buckling mode. While steeper arches are generally more stable in their elastic range, the effect of steepness ratio is reduced as the prestress exceeds 55% of the yield strength. Effects of loading and support conditions have also been considered. Although fixed supports result in more stable arches, their effectiveness depends on the steepness ratio and the level of prestresses. Finally, the effect of strain hardening on the plastic buckling of the arch is more pronounced for lower values of the plastic tangent modulus.

The paper describes a finite element investigation into the buckling, under uniform external pressure, of four submarine pressure hulls. Two of these hulls were traditional ring-stiffened types, but two of these hulls were in the form of corrugated circular cylinders. The latter design was based on an invention by the present author. The investigation found that the new design was structurally efficient and in the case of the smaller vessel, it was found to be structurally more efficient than the conventional design.

Another investigation, based on axisymmetric plastic buckling, was conducted on the two corrugated vessels, to determine if they were prone to collapse through the bellows' mode of failure. This investigation was carried out because former critics of this work stated that the corrugated circular cylinders would fail by the bellows' mode of failure. Neither of the two corrugated pressure hulls was found to fail through the bellows' mode of failure, thereby completely vindicating the present author. The author, however, concludes that the bellows' mode of failure can occur if the cone angles were too large.

Two of the finite element theories were based on the author's work, but the giant computer package ANSYS was also used to study non-symmetric bifurcation buckling. This work was carried out to vindicate the author's in-house computer programs, which were simpler to use than ANSYS.

In this research, 3D analysis model of air-to-air hexagonal plastic plate heat exchanger (HX) is developed numerically and compared with the available experiment. The heat transfer performances with polypropylene (PP) and aluminum (Al) indicate that PP HX can transfer heat as good as Al under this HX application. On the basis of this model, the crest length, the crest pitch and the inlet and outlet chamfer size are designed as three key parameters to improve the heat transfer performances of HX.

Split Hopkinson Pressure Bar (SHPB) has become a frequently used technique for measuring uniaxial compressive stress-strain relationship of various engineering materials under high strain rates. The pulse shape generated in the incident bar is sensitive to the length of the striker bar. In this paper, a finite element simulation of a Split Hopkinson Pressure Bar is performed to estimate the effect of varying length of striker bar on the stress-strain relationship of a material. A series of striker bars with different lengths, from 200mm to 350mm, are employed to obtain the stress-strain response of AL6061-T6 in both simulation and experiment. A comparison is made between the experimental and the computed stress-strain curves. Finally the influence of variation of striker bar length on the sample's stress-strain response is presented.

Soil has obvious plastic characteristic. In civil engineering, some methods, such as reinforcing with natural fibres or synthetic fibres, are often adopted to strengthen soil's bearing capacity or the ability of deformation resistance. Experiences and studies indicate: length, mixture ratio, toughness and fineness of synthetic fibre have rather great influence on the strength of reinforcement soil. In order to further realize the extent of the influence and achieve relatively explicit quantization relation, taking polypropylene fibre as an example, this paper studied the impact rule of the filling quantity of polypropylene fibre (mixture ratio) on mechanical property of reinforcement soil by doing intensity experiments to plain soil and several classes of reinforcement soils with different fibre contents. As the same time, the empirical equation about soil strength varying with fibre content was established by the method of regression analysis. In the end, by simulating reinforcing status with real fibre reinforcement soil and constituting mechanical model according to various fibre contents, the variation situation of stress and strain of soil under loading was numerically simulated based on the plastic assumption about constitutive relation of soil. The study results can be generalized to engineering practice of various polypropylene fibre reinforcement soils.