HYBRID SIMULATION USING MIXED DISPLACEMENT FORCE CONTROL WITH COLUMN SHORTENING COMPATIBILITY
Journal
World Conference on Earthquake Engineering proceedings
Journal Volume
2024
ISSN
30065933
Date Issued
2024
Author(s)
Abstract
This paper presents a series of hybrid simulation (HS) conducted on full-scale steel beam-column connection subassemblages to study the seismic responses of a two-dimensional steel dual frame and special moment frame (SMF), considering first-story steel column shortening caused by local or global buckling during the seismic events. The first case is a seven-story two-bay dual frame system, composed of a SMF and a buckling-restrained braced frame using built-up box columns. The structural analysis program PISA3D was adopted as the analysis engine, connected to the testing facilities at the National Center for Research on Earthquake Engineering (NCREE) through the SFQSST and the Recdex, the general-purpose testing software developed in NCREE. The specimen, a cruciform subassemblage composing of a first-story interior beam-column connection, was loaded through a four degree-of-freedom (DOF) actuation system with mixed displacement and force control modes such that the deformation and the axial force of the column could be experimentally simulated in the HS. The buckling and the resulting shortening of the other first-story columns was numerically simulated using the finite element analysis program ABAQUS. During the HS, buckling developed at the bottom of the interior column and the resulted column shortening was introduced into the step-by-step time integration in the PISA3D analysis via an innovative method. The method utilized a set of equivalent force that enforced displacement compatibility between the physical substructure (PS) and numerical substructure (NS) in the HS. Test results confirmed that the proposed modeling and control methods successfully integrated the experimental substructure and ABAQUS simulation into the HS, resulting in a more realistic frame response with the effect of column shortening captured in the analysis. This paper also presents another series of HS in a second phase, in which the OpenSees was adopted as the analysis engine and the OpenFresco was used as the middle-ware to connect OpenSees and NCREE testing facilities for the purpose of exploring the seismic behavior of a six-story, five-bay steel SMF with first-story, I-shaped column shortening considered. Test results also validated the concept of using equivalent force to enforce displacement compatibility between the PS and the NS for DOF under force control in HS.
Publisher
International Association for Earthquake Engineering
Type
conference paper