Reinforcement of a Small Circular Hole in a Plane Sheet Under Tension

1948 ◽  
Vol 15 (2) ◽  
pp. 160-168
Author(s):  
Samuel Levy ◽  
A. E. McPherson ◽  
F. C. Smith

Abstract This paper presents a theoretical and experimental investigation of the effect of various reinforcements on the stresses and displacements near a small circular hole in a plane sheet under load in its plane. The first part of the paper gives a plane-stress analysis for a reinforcement of variable thickness when the load is a uniform tension in all directions. It is found that a reinforcement which crowds most of the material close to the edge of the hole is most effective in reducing the stress concentration at the hole. The next part presents the principal results of earlier plane-stress analyses for reinforcement by a “doubler plate” when the load is tension in one direction only. The last part describes tests in the elastic range of riveted doubler-plate reinforcements of several sizes and with several rivet arrangements. Details of a test to failure of one reinforcement riveted to one side of the sheet only are given. The tests indicate that the plane-stress theory gives a good estimate of the state of stress outside the reinforcement, and that it may be used for computing median-surface stresses and average elongations of the hole in the specimen, provided that the reinforcement is attached to the sheet by more than one row of rivets.

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7845
Author(s):  
Quanquan Yang ◽  
He Cao ◽  
Youcheng Tang ◽  
Yun Li ◽  
Xiaogang Chen

An experimental investigation is presented for the stress distributions in functionally graded plates containing a circular hole. On the basis of the authors’ previously constructed theoretical model, two kinds of graded plates made of discrete rings with increasing or decreasing Young’s modulus were designed and fabricated in virtue of multi-material 3D printing. The printed graded plates had accurate size, smooth surface, and good interface. The strains of two graded plates under uniaxial tension were measured experimentally using strain gages. The stresses were calculated within the range of linear elastic from the measured strains and compared with analytical theory. It is found that the experimental results are consistent with the theoretical results, and both of them indicate that the stress concentration around the hole reduces obviously in graded plates with radially increasing Young’s modulus, in comparison with that of perforated homogenous plates. The successful experiment in the paper provides a good basis and support for the establishment of theoretical models and promotes the in-depth development of the research field of stress concentration in functionally graded plates.


1954 ◽  
Vol 21 (1) ◽  
pp. 42-44
Author(s):  
H. D. Conway

Abstract Two plane stress problems of elliptical holes in infinite orthotropic sheets are treated: (a) Hole loaded by a pair of concentrated forces acting at the ends of the major or minor axis, and (b) hole in plate which is subjected to uniform tension. The solutions are obtained in a simple manner by transformation from corresponding problems in which the holes are circular. Closed-form expressions are obtained for the stress-concentration factors.


2011 ◽  
Vol 239-242 ◽  
pp. 558-562
Author(s):  
Bu Xi Bian ◽  
Yi Hua Liu

Coating craft process is often used on the hole surface, thus it must affect the degree of the stress concentration near the hole edge. Airy stress function methodology is used to obtain the analytical stress solution for a plate with a small coating circular hole in the center and subjected to the uniaxial uniform tension in this paper. With the help of the finite element software MSC.Patran & Nastran, the K3alloy plate is numerically analyzed, and its coating material is a ZrO2, and with the comparison of the acquired analytical solutions, it can be found that the numerical results coincide with the analytical ones very well. The results show that coating affects greatly the stress distribution near the hole edge, and the stress concentration factor in the coating increases with the coating thickness but decreases in the plate, and it increases with the shear modular ratio of the coating to the plate but decreases in the plate. The effect of the coating on the stress distribution near the hole and the stress concentration cannot be neglected.


2017 ◽  
Vol 68 (6) ◽  
pp. 1267-1273
Author(s):  
Valeriu V. Jinescu ◽  
Angela Chelu ◽  
Gheorghe Zecheru ◽  
Alexandru Pupazescu ◽  
Teodor Sima ◽  
...  

In the paper the interaction of several loads like pressure, axial force, bending moment and torsional moment are analyzed, taking into account the deterioration due to cracks and the influence of residual stresses. A nonlinear, power law, of structure material is considered. General relationships for total participation of specific energies introduced in the structure by the loads, as well as for the critical participation have been proposed. On these bases: - a new strength calculation methods was developed; � strength of tubular cracked structures and of cracked tubular junction subjected to combined loading and strength were analyzed. Relationships for critical state have been proposed, based on dimensionless variables. These theoretical results fit with experimental date reported in literature. On the other side stress concentration coefficients were defined. Our one experiments onto a model of a pipe with two opposite nozzles have been achieved. Near one of the nozzles is a crack on the run pipe. Trough the experiments the state of stress have been obtained near the tubular junction, near the tip of the crack and far from the stress concentration points. On this basis the stress concentration coefficients were calculated.


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