Basic Experimental Studies of the Local Buckling Strength of Carbon Steel Square Pipes with Circular Hole Subjected to Eccentric Axial Compressive Load. 1st Report. In the Case of Equal Eccentric at the Upper and Lower Ends.

Abstract

This paper is concerned with a compression experiment in the case of equal eccentric at upper and lower ends of carbon steel square pipes, each with a circular hole in a short column range, supported by a spherical seat. An empirical formula for calculating eccentric compressive buckling stress σche of the carbon steel square pipes with a circular hole is presented as follows ; σche/σcr=(K0/K)/{1+2(e/c)} where K and K0 = coefficients of axial compressive buckling stress on carbon steel square pipes without and with a cicular hole, e = eccentricity, c = distance between walls. Consideration has been given to the diagram which is the combinatison of the analysis based on the energy method with the experimental results. The measurement results show that this diagram represents good design data and is in good agreement with the results obtained experimentally for a short column range.