Experimental and analytical investigations of steel panel dampers for seismic applications in steel moment frames

Abstract

Summary A ductile Vierendeel frame can be constructed by incorporating steel panel dampers (SPDs) into a moment‐resisting frame (MRF). Thus, the stiffness, strength, and ductility of the lateral force–resisting system can be enhanced. The proposed 3‐segment SPD possesses a center inelastic core (IC) and top and bottom elastic joints. This paper discusses the mechanical properties, capacity design method, and buckling‐delaying stiffeners for the SPDs through the use of cyclic loading tests on 2 specimens. Tests confirm that SPDs' cyclic force vs deformation relationships can be accurately predicted using either the Abaqus or PISA3D model analyses. The paper also presents the capacity design method for boundary beams connected to the SPDs of a typical SPD‐MRF. The seismic performance of an example 6‐story SPD‐MRF is evaluated using nonlinear response history analysis procedures and 240 ground accelerations at 3 hazard levels. Results indicate that under 80 maximum considered earthquake ground accelerations, the mean‐plus‐one standard deviation of the shear deformation of the ICs in the SPDs is 0.055 rad, substantially less than the 0.11 rad deformational capacity observed from the SPD specimens. The experimental cumulative plastic deformation of the proposed SPD is 242 times the yield deformation and is capable of sustaining a maximum considered earthquake at least 8 times before failure. This paper introduces the method of using one equivalent beam‐column element for effective modeling of the 3‐segment SPD. The effects of the IC's relative height and stiffness on the overall SPD's elastic and postelastic stiffness, elastic deformation limits, and inelastic deformational demands are discussed.

Parameter identification for on‐line model updating in hybrid simulations using a gradient‐based method

“…5,10 There are a total of 10 control parameters in the 2-surface model as listed in Table 1. 9 Recently, the applications of parameter identification have migrated from off-line model fitting to on-line model updating. The details of this model are presented later.…”

“…Specifically, the parameter values must be determined via the model fitting procedure to reduce the difference between the analytical results and observed responses. [7][8][9] Recently, a variety of parameter identification methods for on-line model updating have been proposed and adopted for extended applications of advanced hybrid simulations that incorporate on-line model updating. Inevitably, this is a time-consuming task.…”

Hybrid testing with model updating on steel panel damper substructures using a multi‐axial testing system

“…The building and member sizes are symmetric about both the longitudinal and transverse axes, indicating that the structural torsional response about the vertical axis should not exist when subjected to bi‐directional earthquake excitations in the two principal axes. The details of the design procedures and the member sizes of the LFRS for the prototype building have been documented . A three‐dimensional numerical model is constructed for the prototype building using the PISA3D program with built‐in beam‐column and joint elements .…”

“…Appropriate restraints are defined to prevent the axial resisting force from developing in the SPDs. The accuracy of the PISA3D model was proven by comparing it with an Abaqus shell model in a prior study . The fundamental periods are 1.30 and 1.26 seconds in the longitudinal and transverse directions, respectively.…”

“…This study investigates the characteristics and effects of a steel panel damper (SPD) incorporated into a six‐story moment resisting frame (MRF). The proposed SPD is a passive control device that promotes the shear yielding mechanism of a steel wide‐flange section to dissipate the earthquake‐induced input energy . Figure shows the overview and the schematic of an SPD.…”