Advanced Steel Construction

Vol. 2, No.3, pp.242-274 (2006)


MODELING OF THE SEISMIC RESPONSE OF CONCENTRICALLY BRACED STEEL FRAMES USING THE OPENSEES ANALYSIS ENVIRONMENT

 

1Antonio Aguero, 2Carmen Izvernari and Robert Tremblay

1Departmento de mecanica de los medios continuos y teoria de estructuras

ETS de ingenieros de Caminos, Canales y Puertos, Universidad Politecnica de Valencia Campus Vera s/n,46020 Valencia, Espana, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

2Department of Civil, Geological and Mining Engineering

Ecole Polytechnique of Montreal, Montreal(QC) Canada H3C 3A7

 

DOI:10.18057/IJASC.2006.2.3.5

 

ABSTRACT:

A study was performed to investigate the possibility of modeling the seismic inelastic cyclic response of steel bracing members using the OpenSees computer program. The study focuses on bracing members made of rectangular and square steel tubes. The efficiency and the accuracy obtained from the foce (FBE) and displacement (DBE) based elements are first compared. A co-rotational framework is used to model the nonlinear geometric behavior, and inelasticity is accounted for through fiber discretization of the cross-section together with bi-linear or Giuffre-Menegotto-pinto hysteretic material response. FBE and DBE models are compared for various combinations of number of elements along the brace length, number of integration points along the element length, number of fibers used to define the cross-section, and amplitude and number of displacement increments. The influence of brace slenderness and displacement protocol on the accuracy of the models is examined. Model predictions are also compared to individual brace and full-scale frame test results. The influence of time step and brace discretization on the dynamic seismic response for a typical braced steel frame is investigated.

 

Keywords:Displacement based element; Force based element; Braces; Buckling; Yielding; Gusset plate; Frame; Earthquakes; Seismic.

 

Download PDF: