Basic Experimental Studies of the Local Buckling Strength of Carbon Steel Square Pipes with a Circular Hole Subjected to an Eccentric Axial Compressive Load. 3rd Report. In the Case of Eccentric Load at the Upper End and Axial One at the Lower End.

Abstract

This paper describes local buckling strength of carbon steel thin-walled square pipes with a circular hole. Both ends of specimens are supported with spherical seats to aline compressive load. On the upper end eccentric load is applied, but on the lower end loading line is alined to the center of the square pipes. The length of specimens examined is a short column range. An empirical equation of the buckling stress for specimens subjected to the eccentric load is obtained using the ordinary stress, and a ratio of the eccentricity and opening ratio of the square pipes. Experimental results show a good agreement with the proposed equation.