Stress concentration factor due to a functionally graded ring around a hole in an isotropic plate

The aim of this work is to present an analytical solution to reduce the stress concentration factor (SCF) around a circular hole in an isotropic homogeneous plate subjected to far-field uniaxial loading. In this paper the elastic response of an inhomogeneous annular ring made of functionally graded material (FGM), inserted around a hole of a homogeneous plate, is studied. By assuming that Young’s modulus varies in the radial direction with power law and that Poisson’s ratio is constant, the governing differential equations for plane stress conditions are obtained. Using stress function a general solution in explicit closed form is presented and the SCF investigated to highlight the inhomogeneity effects. Furthermore, the explicit solution for an inner homogeneous ring, with different properties with respect to those of the plate, is explicitly obtained and numerical results are compared between homogeneous ring and FGM ring.     

Stress concentration around a curvilinear hole in plates and shells

Azerbaidzhan Economic Institute, Baku. Translated from Prikladnaya Mekhanika, Vol. 27, No. 1, pp. 71–77, January, 1991.     

Stress concentration around a circular hole in a transversely isotropic spherical shell

Analytical expressions for the stresses near a circular hole in a transversely isotropic shallow spherical shell under uniform pressure are derived. The form of the solution depends on the range of change in the compliance to transverse shear. The influence of the relative radius of the hole and the compliance to transverse shear on the stress concentration is analyzed.__________Translated from Prikladnaya Mekhanika, Vol. 40, No. 12, pp. 99–106, December 2004.     

横向爆炸载荷下开孔板的动应力集中因子

基于ANSYS 5.7/LS-DYNA程序,对3 m3 m0.25 m四边固支和简支、中心具有0.3 m0.3 m方孔的开孔板和无孔板对应点在两种下三角爆炸载荷作用下的应力响应进行了分析;由开孔板和无孔板边对应点的主应力时程曲线,对提出的能量密度时间分布函数的绝对值平方进行变上限积分,按其比值确定动应力集中因子,该方法简单易行。     

Displacement field around a circular hole in a viscoelastic plate

Moiré experimental techniques are used to measure displacement fields in viscoelastic plates undergoing large deformations at elevated temperatures. These experimental procedures are applicable to determining displacement fields in nonlinear materials. As preliminary information, the material properties are determined from creep studies. The moiré method is used to determine the strains under constant load and isothermal conditions. Tests are conducted for several combinations of load and temperature for 2.5 decades of time. Assuming thermorheologically simple behavior, the data are shifted to establish the creep extensional compliance over ten decades in time. The constitutive equations are formulated as integral equations, the kernels of which are the functions that were measured in this work. These equations are solved exactly for the infinitesimal case. The finite case is then approximated by an incremental superposition of a series of successiye infinitesimal solutions. The results are applied to a plate initially containing a circular hole, and are shown to agree closely with the experimental measurements.     

Stress concentration around a small spherical inhomogeneous inclusion on the axis of a circular cylinder in torsion

Stresses are calculated for a small elastic inclusion bonded (in a way to ensure continuous displacements and tractions across the surface of the inclusion) to a large circular cylindrical shaft. The inclusion considered is inhomogeneous and of spherical shape. The shear modulus of the inclusion is assumed to be μ₀ exp(−1/2β² r ²). Some special cases are also discussed.     

Stress state around cracks on the boundary of a hole in a photoelastic orthotropic plate under creep

The stress–strain state near cracks on the boundary of a circular hole in a linear elastic orthotropic composite plate under tension is analyzed. The distribution of stress intensity factors (SIFs) at the crack tip is found from photoelectric measurements. The dependence of the SIFs on the ratio of crack length to hole radius and on the mechanical properties of the material is established     

Stress concentration factors due to the bending of a thick plate with circular hole

Summary Solutions of a biharmonic equation together with four Helmholtz equations governing a twelfthorder thick plate theory in cylindrical coordinates are derived in a form suitable for finding corrections to previous lower-order thick plate results. As an example, for an infinite plate with a circular hole subjected to bending moments at two parallel outside edges, detailed comparisons of values of a stress couple concentration factor and a stress concentration factor are made between the present theory and previous results due to Alblas, Reissner, and Cheng.

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Spannungskonzentrationsfaktoren für die Biegung dicker Platten mit Kreisloch

Übersicht Für die Grundgleichungen einer Theorie 12. Ordnung für dicke Platten, bestehend aus einer biharmonischen Gleichung und vier Helmholtz-Gleichungen, werden in Polarkoordinaten Lösungen bestimmt, um Korrekturen zu früheren Ergebnissen nach Theorien geringerer Ordnung angeben zu können. Als Beispiel werden für eine unendliche, an zwei parallelen Seiten durch ein Biegemoment belastete Platte mit Kreisloch die Konzentrationsfaktoren für Biegemoment und Randspannung verglichen, die sich nach der hier benutzten Theorie und aus früheren Arbeiten von Alblas, Reissner und Cheng ergeben.