Tests and model calibration of high‐strength steel tubular beam‐to‐column and column‐base composite joints for moment‐resisting structures

Abstract

Performance-based engineering (PBE) methodologies allow for the design of more reliable earthquakeresistant structures. Nonetheless, to implement PBE techniques, accurate finite element models of critical components are needed. With these objectives in mind, initially, we describe an experimental study on the seismic behaviour of both beam-to-column (BTC) and column-base (CB) joints made of high-strength steel S590 circular columns filled with concrete. These joints belonged to moment-resisting frames (MRFs) that constituted the lateral-force-resisting system of an office building. BTC joints were conceived as rigid and of partial strength, whereas CB joints were designed as rigid and of full strength. Tests on a BTC joint composed of an S275 steel composite beam and high-strength steel concrete-filled tubes were carried out. Moreover, two seismic CB joints were tested with stiffeners welded to the base plate and anchor bolts embedded in the concrete foundation as well as where part of a column was embedded in the foundation with no stiffeners. A test programme was carried out with the aim of characterising these joints under monotonic, cyclic and random loads. Experimental results are presented by means of both force-interstory drift ratio and moment-rotation relationships. The outcomes demonstrated the adequacy of these joints to be used for MRFs of medium ductility class located in zones of moderate seismic hazard. Then, a numerical calibration of the whole joint subassemblies was successfully accomplished. Finally, non-linear time-history analyses performed on 2D MRFs provided useful information on the seismic behaviour of relevant MRFs. Copyright plastic hinge located on the column outside the plinth detected by computing the difference between I-1 and I-0 (Figure 8(c) and (d)). Collapse was caused by brittle failure of the column wall near the weld between the column and the base plate owing to phenomenon of local instability in the wall of the column, as depicted in Figure 12(d). In this case, plastic rotations exceeded 45 mrad. Finally, with reference to CB joints, no requirements of a minimum plastic rotation are provided in EN1998-1 [23]. Figure 11. Force-interstorey drift ratio curves and moment-rotation relationships: (a) CBJSEE, (b) CBJSER, (c) CBJINE and (d) CBJINR.

Multi-Span Steel–Concrete Bridges With Anti-seismic Devices: A Case Study

“…Modern design codes give the possibility to apply design methodologies assisted by testing (Pucinotti et al, 2015); in fact, EN1990 (Section Comparisons and Annex D) and EN1993-1-3 (CEN, 2002(CEN, , 2006 contain specific rules and guidance to the design assisted by testing. In the current case study, before the devices' installation, an accurate analysis of seismic behavior and the matching of functional curves with the design assumptions were conducted.…”

“…Moreover, the following parameters were assigned: Figure 6 shows the force-velocity relationship for the OP 300/175 and OTP50/300 devices; in the same figure, the comparison between theoretical and experimental constitutive law for these devices (OP and OTP) is presented. Moreover, in order to obtain further control of the results and to provide useful information on the seismic behavior, both Incremental Dynamic Analyses (IDA) and Linear Modal Analyses (LMA) were carried out (Pucinotti et al, 2015). The non-linear dynamic analysis outcomes were compared with those from the modal analysis that used a design response spectrum, in order to analyze the differences in terms of global shear force at the base of the structures.…”

10.07: Numerical analysis of the fire resistance of high‐strength steel circular columns

“…Thus, the buckling reduction coefficient at elevated temperature χfi.θ was determined according to Eq. (2).…”

“…in steel braced frames, or when the columns are stocky [1]. Moreover, in moderate seismic-prone regions, columns in moment-resisting frames (MRFs) designed in HSS and beams in mild steel can represent an effective solution when the limitation of lateral displacements is not dominant [2]. Circular columns are suitable in structures subjected to loading in multiple directions, like welded steel frames, because of uniform geometrical characteristics along all crosssectional directions.…”

Block shear failure of S275 and S690 steel angles with single-line bolted connections

“…The load demand on foundations can also be reduced by using a lighter superstructure constructed of HSS members. The attractiveness of HSS construction has stimulated research on HSS material properties [17][18][19][20], HSS-based connections/components [21][22][23][24],…”