Crisafulli and Restrepo 2003
The response of a connection detail for coupling precast concrete walls in low to medium rise buildings was considered both analytically and experimentally in this research. In this paper, the behavior of isolated connecting plates was experimentally studied in order to investigate the performance of the welded connection. The connection consists of a rectangular steel plate with a concentric circular perforation. Weak and ductile links are formed and energy dissipation takes place in the connections.
System Concept
Welded connections are one of the connection approaches to join precast concrete elements. In this research, wall panels were connected through steel plates along a vertical joint. Precast concrete parts were connected to each other by means of perforated steel plates. The weld plates were designed as weak links, so that energy dissipation occurs there, allowing the plates to act as coupling beams.
Experimental Study, Results, and Discussion
Two stiff framed steel plates were used in the test specimen, with two connecting perforated steel plates welded to each face of the framed steel plates. The use of two connecting perforated steel plates was required to obtain a symmetric configuration and avoid out-of-plane movement. A reverse cyclic quasi-static load-displacement test was applied to the specimen to capture some of the features induced by seismic events.
Shear force vs. vertical displacement plots from the test yielded a hysteretic response of the connection. The hysteretic loops were stable and exhibited no stiffness or strength degradation, even though the specimens were subjected to relatively large displacements. Additionally, perforated plates have very ductile behavior. Neither buckling, nor cracking were observed at the maximum ductility level. Extensive yielding was detected in the connections, indicating energy dissipation.
An analytical model with response predictions was created prior to the test, assuming that the fillet welds represent a fixed boundary for the perforated steel plate. However, the experimental results showed that this assumption is not realistic. The experimental value of the stiffness of the welded plate was smaller than that calculated using this hypothesis.
Reference
Crisafulli, F. J. and Restrepo J. I. (2003). “Ductile Steel Connections for Seismic Resistant Precast Buildings,” Journal of Earthquake Engineering, Vol. 7, No. 4, pp. 541-554.