Numerical modeling of single-storey precast frame's pinned connections with a special damper

Abstract

Single-storey precast frames with pinned beam-column connections are widely used in Turkey. This type of precast structures had suffered extensive damages during the recent major earthquakes (Ceyhan (1998), Kocaeli (1999), Duzce (1999)). The damages had been generally concentrated on the pinned connections as failure of dowels or at the column bases as large plastic deformations. A special lead extrusion damper (LED) has been developed in an ongoing PhD study in Istanbul Technical University. The damper is going to be installed into the pinned connection regions of the single storey precast frames. Nearly half scaled specimens representing existing features of precast frames are planned to be tested on the shake table. Prior the experimental work, an extensive blind prediction study has been carried out through the nonlinear dynamic time history analyses of the numerical models which are representing the specimens with and without damper. The numerical models are generated with Seismostruct. The comparison of the structural behaviors between the bare frame and the frame with LED has been discussed. Although the relative drifts of the precast frame has been significantly reduced, the observed base shear demand moderately increased by the installation of the LED.