Experimental and numerical studies on the buckling of the hemispherical shells made of maraging steel subjected to extremely high external pressure

Abstract

This work is devoted to the nonlinear buckling of the hemispherical shells subjected to extremely high external pressure. The shells are made of maraging steel with yield strength of 2100 MPa. The experiment on a tentatively devised laboratory-scale hemispherical shell is conducted in high pressure chamber, after preciously fabricated, optically and ultrasonically measured. Numerical predictions are carried out and proved to have a good agreement with experimental results. The laboratory-scale hemispherical shell can borne the pressure as high as about 139 MPa and demonstrates an unstable post-buckling character and a local dimple post-buckling mode near the base. Based on the study, a segmented hemispherical configuration is conceived and evaluated numerically, which can provide a reference for the deep-sea pressure hull design made of maraging steel.