Experimental and analytical investigation of the ‘compression zone’ component within a steel joint at elevated temperatures

At ambient temperature, researchers [Comput. Struct. 2 (1972) 253; AISC Engng J. (1984) 161; J. Construct. Steel Res. 45 (1998) 1] have focused on producing simplified models in order to predict the ultimate capacity of a column web subjected to transverse compressive forces and thereby assist engineers to design steel joints efficiently. Another reason for producing these models was to eliminate the use of column web stiffeners, which are expensive to install and interfere with the weak-axis framing of beams into the column. The resistance to concentrated forces is a very complex problem in which it is almost impossible to derive closed theoretical solutions. Therefore, studies aiming at predicting the ultimate resistance of column webs to concentrated forces tend towards empirical solutions. The problem becomes more complicated when another variable, such as temperature, is introduced. This paper reports how existing empirical models at ambient temperature, contained in design codes and standards, may be modified for application at elevated temperatures. # 2003 Elsevier Ltd. All rights reserved.