Toward a Probabilistic Preliminary Design Criterion for Buckling Critical Composite Shells

Autor: Mark W. Hilburger, Johann Arbocz
Rok vydání: 2005
Předmět:
Zdroj: AIAA Journal. 43:1823-1827
ISSN: 1533-385X
0001-1452
DOI: 10.2514/1.11368
Popis: A probability-based analysis method for predicting buckling loads of compression-loaded laminated composite shells is presented, and its potential as a basis for a new shell-stability design criterion is demonstrated and discussed. In particular, a database containing information about specimen geometry, material properties, and measured initial geometric imperfections for a selected group of laminated-composite cylindrical shells is used to calculate new buckling-load knockdown factors. These knockdown factors are shown to be substantially improved and hence much less conservative than the corresponding deterministic knockdown factors that are presently used by industry. The probability integral associated with the analysis is evaluated by using two methods; that is, by using the exact Monte Carlo method and by using an approximate first-order second-moment method. A comparison of the results from these two methods indicates that the first-order second-moment method yields results that are conservative for the shells considered. Furthermore, the results show that the improved, reliability-based knockdown factor presented always yields a safe estimate of the buckling load for the shells examined.
Databáze: OpenAIRE