Static behavior of K-joints stiffened with eXternal plates under aXial loads at ambient and different elevated temperatures

In the present work, the effect of the outer reinforcing plate on the initial stiffness, ultimate strength, and failure mechanisms of tubular K-joints under axial load at ambient and different fire conditions are evaluated. In the first phase, a finite element (FE) model was generated and verified by ۱۳ experimental tests. In the next step, ۱۰۵۷ numerical models were generated. In these models, the welds joining the chord and braces were modeled. Using the produced FE models, the structural behavior under ambient and different elevated temperatures (۲۰, ۱۵۰, ۳۰۰, ۴۵۰, ۶۰۰, ۷۵۰, and ۹۰۰ ºC) was evaluated. Results showed that the outer plate can enhance the ultimate strength up to ۳۱۹% under fire conditions. Despite the considerable effect of the outer plate on the stiffness, ultimate strength, failure modes and the frequent usage of the K-joints in tubular structures, the static response of the reinforced K-joints at ambient and elevated temperatures has not been studied

کلیدواژه ها:

K-joints ، fire conditions ، eXternal plates ، ultimate strength ، failure mechanisms