Experimental study of inelastic buckling strength and stiffness requirements for longitudinally stiffened panels

An experimental study was conducted in order to verify a proposed equation for the minimum required stiffness for longitudinal stiffeners attached on compression plates. Nine test specimens of stiffened plates were fabricated and tested to their ultimate strengths. Test results are compared with the maximum strengths predicted for stiffened plates by finite element analysis and by the proposed SSRC type critical stress curve. Fairly good correlations were observed, thereby confirming experimentally the adequacy of the proposed equation for the minimum required stiffness of the longitudinal stiffener attached to the compression panel and a modified SSRC type critical stress curve encompassing both the buckling ranges of plastic yield and the transition zones. A set of conclusions is drawn from the experimental studies as to the buckling behaviors of stiffened plates.