A STUDY OF JONES EQUATION FOR BUCKLING OF LAMINATED COMPOSITE CYLINDERS UNDER EXTERNAL HYDROSTATIC-PRESSURE

A classical solution derived by Jones (1968) is used to evaluate the b uckling performance of unstiffened generally orthotropic and quasi-iso tropic laminated Graphite/Epoxy (GREP) composite cylinders subjected t o external hydrostatic pressure. The results of the analysis are compa red to finite-element analysis results. Hydrostatic testing to failure of several 12-ply T300/5208 GREP cylinders demonstrated that the clas sical buckling solution is quite accurate. The finite-element results showed good agreement with both Jones' solution and test data, with se veral notable exceptions. Evaluation of strain gage data via Southwell 's (1932) method indicates that the test cylinders were fabricated ver y nearly true. A postiori buckling predictions using Southwell plots a ll compared quite favorably with the Jones' equation predictions. This work demonstrates that a relatively simple analytical solution can re liably evaluate the performance of composite materials in pressure hul l applications.