摘要:
Experimental investigation of 19 full-size steel columns was undertaken to disclose (a) the merit of a lateral stay member that does not fix the direction of the column at the point of support, (b) the effectiveness of a stay member that connects to one edge only of the column width, (c) the effect on the required lateral support of initial column curvature or eccentricity, and (d) the maximum stress for which a stay member should be proportioned.The results obtained appear to warrant the following conclusions:(1) The percentage increase in the ultimate capacity of columns due to the introduction of lateral support is greatest for columns with high slenderness ratios and least for those with low slenderness ratios.(2) For a column hinged at both ends, and having end eccentricity of loading up to one-eighth of the column width in the direction of bending, the introduction of lateral support at mid-height, without rotational fixing at this point, raises the strength to from 2. 70 to 4.87 times the theoretical strength of the full-length column as computed by the secant formula.(3) The necessary lateral supporting force of an eccentrically loaded, deflected column, where the lateral force is applied at the middle of the width of the section, is given with sufficient exactness by Equation (22),(4) The relation between the necessary lateral supporting force applied at the edge of the section and that applied at the middle of the section width for a given deflection of the flange under consideration is given satisfactorily by Equation (23). For the test columns, which had widths of section normal to the plane of bending varying from 6 in. toin. and were subjected to loads up to 2.5 times the Euler load for a laterally unsupported column, the lateral supporting force when applied to the edge of a flange was in no case more than 15% greater than that which would have been necessary if applied to the middle of the web at the same flange deflection.
ISSN:1923-4287
DOI:10.1139/cjr42a-011
出版商:NRC Research Press
年代:1942
数据来源: NRC