A Procedure for the Assessment of the Behaviour Factor for Steel MRF Systems Based on Pushover Analysis

Abstract

Abstract. To

A multi‐hazard analysis framework for earthquake‐damaged tall buildings subject to thunderstorm downbursts

“…In Figure 4A, the yield point at the intersection of the red dashed lines is identified, following Castiglioni et al 43 The intersection is defined by the projected gradient of elastic stiffness and the maximum base shear.…”

Structural behaviour of stainless steel frames. Safety against accidental seismic actions

“…It is well-assumed that the behaviour factor should consider the reserve of strength due to the redundancy of the structure and the oversizing in the elements, the energy dissipation capacity of the structure (ductility), and the structural damping (Uang et al 1991;Whittaker et al 1999;Zeris et al 2014;Ferraioli et al 2014;Castiglioni et al 2017;Vamvatsikos et al 2020). Based on this definition, the overall behaviour factor can be expressed as shown in Eq.…”

“…8.15, where 𝑞 𝛺 is the general overstrength factor -𝑞 𝛺 can be split into the 𝑞 𝑅 factor, which accounts for the overstrength due to the redistribution of seismic action effects in redundant structures, and the 𝑞 𝑆 factor, which accounts for the overstrength due to other sources -, 𝑞 𝐷 is the factor pertinent to ductility, and 𝑞 𝜁 is the factor that reflects the influence of damping effects. It should be noted that the same damping values are generally considered for elastic and inelastic analyses (𝑞 𝜁 =1) (Whittaker et al 1999;Zeris et al 2014;Ferraioli et al 2014;Castiglioni et al 2017), which results in the computation of the behaviour factor proposed by prEN 1998-1-2 (2021) (see Eq. 8.2).…”

“…8.16 as the ratio of the shear force at which the global inelastic behaviour initiates 𝑉 𝑦 and the shear force at which the first local yielding occurs at any member 𝑉 1,𝑦 . In addition, when the fundamental period is higher than 0.5 s (Castiglioni et al 2017), the ductility factor 𝑞 𝐷 can be defined in terms of the horizontal displacements as given in Eq. 8.17, i.e., as the ratio of the inelastic ∆ 𝑢 and elastic ∆ 𝑦 drift values at the ultimate resistance.…”

“…To compute the behaviour factor value, the inelastic resistance-displacement response obtained from the pushover analysis may be idealised into a bilinear response defined by the three pair of points shown in Eq. 8. consensus on the definition of these points from the results of the pushover analysis (Castiglioni et al 2017). prEN 1998-1-1 (2021 states that the force-deformation capacity curve may be idealised into a bilinear relationship similar to that shown in Figure 8.6.…”