A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
The stress concentration factor in the vicinity of a hole as obtained by anisotropic elasticity (Lekhnitskii's solution) is presented. The effect of finite size panels is accounted for by introducing a finite width correction factor. It is shown from test results that using the stress concentration factor in design is very conservative. Other methods for predicting failure of composite panels with holes are presented and discussed with emphasis on the Whitney and Nuismer approach where stresses are evaluated at a characteristic distance or are averaged over a characteristic distance in the vicinity of the hole. An improved Whitney‐Nuismer approach is presented to calculate the characteristic averaging distance instead of using a single value for different laminates. This is done by introducing a curve of complete notch sensitivity and using the averaging distance for the special case where the amount of material next to the hole is just enough to allow stress redistribution. This improved approach is shown to be in good agreement with test results for a wide variety of laminates. On the basis of this approach, robust and near optimum laminate layups that minimize the effect of the hole and lead to high failure stresses are presented.
The stress concentration factor in the vicinity of a hole as obtained by anisotropic elasticity (Lekhnitskii's solution) is presented. The effect of finite size panels is accounted for by introducing a finite width correction factor. It is shown from test results that using the stress concentration factor in design is very conservative. Other methods for predicting failure of composite panels with holes are presented and discussed with emphasis on the Whitney and Nuismer approach where stresses are evaluated at a characteristic distance or are averaged over a characteristic distance in the vicinity of the hole. An improved Whitney‐Nuismer approach is presented to calculate the characteristic averaging distance instead of using a single value for different laminates. This is done by introducing a curve of complete notch sensitivity and using the averaging distance for the special case where the amount of material next to the hole is just enough to allow stress redistribution. This improved approach is shown to be in good agreement with test results for a wide variety of laminates. On the basis of this approach, robust and near optimum laminate layups that minimize the effect of the hole and lead to high failure stresses are presented.
Holes
Kassapoglou, Christos (author)
2015-03-16
32 pages
Article/Chapter (Book)
Electronic Resource
English
Online Contents | 1998
| British Library Online Contents | 2012
Cuting holes for testing vs. testing for holes
Tema Archive | 2003