Experimental and numerical analyses on buckling and strength failure of composite cylindrical shells under hydrostatic pressure

The buckling and strength failure of composite cylindrical shells under hydrostatic pressure are studied in this paper by experimental tests and finite element method. Experimental tests were carried out for three composite cylindrical shells with different stacking sequences. In parallel, finite element models are built to predict the buckling and strength failure pressures. The finite element results agree well with the corresponding experimental tests. A parametric study is conducted and the effects of length-radius ratio, thickness-radius ratio, ply angle and stacking sequence on the critical buckling pressure and strength failure pressure are discussed. The results show that length-radius ratio has little influence on the strength failure pressure while thickness-radius ratio, ply angle and stacking sequence have significant influences on the critical buckling pressure and strength failure pressure. The boundary line formed by the intersections between the critical buckling pressure and strength failure pressure of composite shells with same configuration is nonlinear and it is a function of length-radius ratio, thickness-radius ratio, ply angle and stacking sequence.