The development of new high-strength steels of strengths greater than that of steel to BS 968 has necessitated the examination of their structural behaviour in order to formulate design rules. This paper presents the results of 130 strut tests on one such steel of 447 MN/m2 (29 ton/in2) yield stress. Five sections, of different geometry, were studied, and the effect of stress relieving on stub columns investigated. These tests were carried out over a range of slenderness ratios from which is derived a strut curve. This is compared with those extrapolated from the formulas in BS 153 and BS 449 and is found to lie above both for all slenderness ratios. Thus it is concluded that these formulas may safely be applied to the design of struts in steel with a yield stress up to 463 MN/m2 (30 tonf/in2) for both bridges and structures. G. Strymowicz and P.D.M. Horsley
The mechanics of the structural action in torsion of the core walls in tall buildings is examined in this paper. The coupling effect of the floor beams on the separate walls is considered and a general solution to the resulting differential equation is derived. Expressions for the wall bending moments, the beam shear forces and the wall displacements are given. The correlation of this theory with published test values is examined. Graphs of numerical values are given and an example is calculated to illustrate the order of the effect of the wall coupling. Duncan Michael
The paper reviews the current effective width treatments in BS 153 and BS 449 for plates in compression, and compares them with recent research results. Interaction between local buckling and overall column buckling is considered. New design rules are tentatively suggested. Particular reference is made to the effect of residual stresses caused by welding, and an approximate method is presented for relating residual stress to size of weld. J.B. Dwight and K.E. Moxham