A Simplified Approach for the Corrosion Fatigue Assessment of Steel Structures in Aggressive Environments

Abstract

Fatigue performance is often a key aspect when dealing with existing steel structures such as steel bridges or offshore constructions. This issue proves to be more critical as these structures are usually located in aggressive environments and are thus exposed to progressive degradation. Indeed, disruptive phenomena such as corrosion can severely worsen the fatigue performance of the steel components. Currently, the normative standards do not provide a codified procedure for the fatigue checks of steel structures subjected to ongoing corrosion. Within this framework, in this paper a simplified approach for the life-cycle assessment of corroded steel structures is proposed. For this purpose, the concept of “critical corrosion degree” is introduced, allowing the expression of corrosion fatigue checks in a more direct “demand vs. capacity” form with respect to the currently available methods. A first validation of such methodology is reported for the corrosion fatigue tests drawn from the literature. The predicted levels of critical corrosion are in good agreement with the values of artificially induced corrosion (i.e., 4, 8, and 12% of mass loss, respectively), with a maximum relative error of ≈9.3% for the most corroded specimen. Finally, parametrical analyses are performed, highlighting the influence of the model parameters on the corrosion fatigue performance of the steel elements.

Seismic Strengthening of an Existing Rc Frame Building Designed for Gravity Loads

“…In fact, the use of steel as a construction material allows for sustainable, high-performance, and fast application interventions [17][18][19][20][21][22][23][24]. The high structural performance of steel systems is widely reported in numerous works in literature [25][26][27][28][29][30][31][32][33][34][35][36][37][38]. Therefore, starting from the result of the pushover analyses performed on the existing structure, the dimensioning of the orthogonal steel exoskeleton strengthening intervention was carried out following a step-by-step procedure properly introduced by the Authors in a previous publication [39].…”

Evaluation of the influence of mean stress on the fatigue behavior of notched and smooth medium carbon steel components through an energetic local approach

“…As widely recognized in literature, 4–8 the presence of tensile mean stresses detrimentally affects the cyclic performance of components, as tension promotes crack opening and propagation 9 . To this end, it is worth mentioning that several simplified criteria can be found in literature to account for mean‐stress effect, for example, the Goodman, 10 Gerber, 11 and Soderberg 12 criteria or the Smith–Watson–Topper (SWT 13 ) and Walker 14 criteria.…”

“…1 A typical example is represented by mechanically fastened joints, 2 in which high-strength bolts should endure repeated tensile and/or shear loads while subjected to strong clamping stresses induced by preloading, for example, up to 0.7 times their tensile design resistance according to European EN1993:1-8 provisions. 3 As widely recognized in literature, [4][5][6][7][8] the presence of tensile mean stresses detrimentally affects the cyclic performance of components, as tension promotes crack opening and propagation. 9 To this end, it is worth mentioning that several simplified criteria can be found in literature to account for mean-stress effect, for example, the Goodman, 10 Gerber, 11 and Soderberg 12 criteria or the Smith-Watson-Topper (SWT 13 ) and Walker 14 criteria.…”

Seismic Assessment of the Steel Moment Resisting Frame Equipped With Friction Beam-to-Column Joints

“…Steel structures are widely used in seismic areas [1][2][3][4][5][6][7][8][9][10][11] since, if properly designed, they can provide large dissipation of earthquake energy exploiting the material ductility [12][13][14]. In this work, the seismic assessment of steel moment resisting frames, equipped with friction beam-to-column joints developed through FREEDAM project, was investigated.…”