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The second part of the two companion papers investigates the tensile properties of corroded steel structures numerically at connections. However, the design and calculation methodology of steel structures that are influenced by corrosion has not been proposed. This study simultaneously evaluated the tensile behavior of 4 types of artificially corroded steel members with concrete specimens in 100, 200, 400, and 600 cycles, and non-linear finite element methods (F.E.M) are also performed to assess the tensile behavior of corroded specimen over time. Based on the obtained results, finite element method model can be totally replaced experimental to analyze tensile properties of corroded steel structure at connections cause the error between F.E.M and the experiment is less than 3% in term of loading such as ultimate load, fracture load, yield load and at the same time F.E.M can ultimately find out all the characteristics of the corrosion surface geometry such as displacement, cracks, destructive cross-sections, stress distribution. F.E.M can determine the failure cross-section of any corroded steel members. Accordingly, the influence effective thickness for the design and calculation of the corrosion-resistant steel structure overtime is also proposed based on the average depth of corrosion and standard deviation. [ABSTRACT FROM AUTHOR]

3D printing offers great potential for developing complex flexure mechanisms. Recently, thickness-correction factors (TCFs) were introduced to correct the thickness and stiffness deviations of powder-based metal 3D printed flexure hinges during design and analysis. However, the reasons for the different TCFs obtained in each study are not clear, resulting in a limited value of these TCFs for future design and fabrication. Herein, the influence of the porous layer of 3D printed flexure hinges on the hinge thickness is investigated. Samples of parallelogram flexure mechanisms (PFMs) were 3D printed using selective laser melting (SLM) and 316L stainless steel powder. A 3D manufacturing error analysis was completed for each PFM sample via 3D scanning, surface roughness measurement and morphological observation. The thickness of the porous layer of the flexure hinge was independent of the designed hinge thickness and remained close to the average powder particle diameter. The effective hinge thickness could be estimated by subtracting twice the value of the porous layer thickness from the designed value. Guidelines based on finite element analysis and stiffness experiments are proposed. The limitations of the presented method for evaluating the effective hinge thickness of flexure hinges 3D printed via SLM are also discussed. [ABSTRACT FROM AUTHOR]

We present the results of experimental studies of the dependence of the diffraction efficiency of nonoblique transmission holograms formed in the sample of a (īī0)-cut photorefractive piezoelectric Bi1SiO crystal on the sample thickness and orientation angle of the grating vector at two fixed mutually orthogonal orientations of the linear polarization vector of the reading beam. It is shown that only if along with optical activity of the crystal, the electrooptic, inverse piezoelectric, and photoelastic effects are taken into account in the analytical diffraction model, it is possible to carry out satisfactory theoretical interpretation of the experimental data. [ABSTRACT FROM AUTHOR]

Approximate methods for calculating laminated glass (LG), a composite where thin polymeric layers are sandwiched by glass plies, are very useful in the design practice. The most common approach relies upon the definition of the effective thickness, i.e., the thickness of a glass monolith that, under the same boundary and load conditions, presents the same maximal stress or deflection of the laminate. Different alternative formulations have been proposed, but for flat glass only. Meeting the increasing interest for curved glazing in modern architecture, here the recent 'Enhanced Effective Thickness' method is extended to the case of single-curvature LG panels. Under the assumption that the curvature is moderate, usually met in the practice, simple formulae for the effective thickness are proposed. A practical method is presented to calculate the relevant coefficients, which depend upon the geometry, load and boundary conditions. Comparison with numerical experiments in paradigmatic examples confirms the accuracy of the proposed approach. [ABSTRACT FROM AUTHOR]

Three-layer slab waveguide with left-handed materials (LHM) is discussed using the Maxwell’s equations and their equations of dispersion relation for TM modes are obtained. By seeking the power of the slab waveguide, their equations of effective thickness for TM modes are obtained. Furthermore, the interrelated equations for right-handed materials (RHM) slab waveguide are introduced and their curves plotted. To find new properties for LHM slab waveguide, the equations and their curves for the LHM and RHM slab waveguide are compared respectively. [ABSTRACT FROM AUTHOR]

A finite element vibration analysis of thin-watled cylindrical shells conveying fluid with uniform velocity is presented The dynamic behavior of thin-walled shell is based on the Sanders’ theory and the fluid in cyhndrical shell is considered as inviscid and incompressible so that it satisfies the Laplace’s equation A beam-like shell element is used to reduce the number of degrees-of-freedom by restricting to the circumferential modes of cylindrical shell An estimation of frequency response function of the pipe considering of the coupled effects of the internal fluid is presented A dynamic coupling condition of the interface between the fluid and the structure is used The effective thickness of fluid according to circumferential modes is also discussed The influence of fluid velocity on the frequency response function is illustrated and discussed The results by this method are compared with published lesults and those by commercial tools [ABSTRACT FROM AUTHOR]

Thickness is not a well-defined quantity for two-dimensional (2D) materials. Hence, there are several choices adopted widely to assign the thickness of a 2D nanosheet: (a) the interlayer distance in layered bulk crystals; (b) the vertical distance between outmost atoms; (c) the value of (b) plus atomic van der Waals radius. Except these definitions of thickness, we determine the effective thickness of 2D pnictogen nanosheets based on continuum elastic theory combined with first principle calculations, from which the tension rigidities are extracted by fitting the strain energies of biaxially stretched samples with a quadratic relation on the lateral and transversal strains for blue phosphorene, arsenene, and antimonene. Whereas the bending rigidities are computed from the pnictogen nanotubes rolled from flat 2D nanosheets. Given the tension and bending rigidities, the effective thickness could be determined from the ratio between these two quantities. Our results indicate that the effective thickness, being much smaller than the widely used interlayer distance in the corresponding bulk material, is suited to describe mechanical properties of 2D nanosheets in a consistent way. [ABSTRACT FROM AUTHOR]