Influence of variability of material mechanical properties on seismic performance of steel and steel–concrete composite structures

Abstract

Modern standards for constructions in seismic zones allow the construction of buildings able to dissipate the energy of the seismic input through an appropriate location of cyclic plastic deformations involving the largest possible number of structural elements, forming thus a global collapse mechanisms without failure and instability phenomena both at local and global level. The key instrument for this purpose is the capacity design approach, which requires an appropriate selection of the design forces and an accurate definition of structural details within the plastic hinges zones, prescribing at the same time the oversizing of non-dissipative elements that shall remain in the elastic field during the earthquake. However, the localization of plastic hinges and the development of the global collapse mechanism is strongly influenced by the mechanical properties of materials, which are characterized by an inherent randomness. This variability can alter the final structural behaviour not matching the expected performance. In the present paper, the influence of the variability of material mechanical properties on the structural behaviour of steel and steel/concrete composite buildings is analyzed, evaluating the efficiency of the capacity design approach as proposed by Eurocode 8 and the possibility of introducing an upper limitation to the nominal yielding strength adopted in the design

Experimental tests on real-scale EBF structures with horizontal and vertical links

“…HEA100 profiles with length equal to 300 mm for the horizontal link and HEB120 profiles of length equal to 150 mm for the vertical link were selected. The design of non-dissipative elements was executed following the EN 1998–1:2005 and in agreement to what specified in the current literature [5] , [6] , [7] . The ratio V y,link /V Ed was assumed unitary considering the achievement of the complete plastic deformation of the link during the tests; eventual higher over-strength was accounted for assuming Ω factors equal to 2.0.…”

Rintc-E: Seismic Risk of Pre-Code Single-Story Non-Residential Steel Buildings in Italy

“…In fact, brace fracture was assumed to occur when the maximum brace strain range (Δεpeak) reached the limit value by Hsiao et al [12]. Similarly, column base anchor fracture was assumed to occur when the peak strain in the anchors (εpeak) exceeded the expected steel ultimate strain (εu=34%, [19]).…”

Design and Analysis of Automated Rack Supported Warehouses

“…The compressive behaviour was calibrated basing on preliminary numerical simulation on single brace elements. A simple fibre model was realized using OpenSees ® [19] following methods widely presented in the current scientific literature [20,21,22]. An initial imperfection, equal to 1/500 of the total length of the element, was applied to model bucking phenomena; a constitutive elastic-perfectly plastic law was adopted for the material.…”