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concrete frames are among the main topics studied. Korkmaz and Tankut [12] tested six beam-to-beam connection subassemblies under reversed cyclic loading. The behavior of the precast mem- bers was compared with that of the monolithic specimen. In order to improve the seismic performance of the connection, several rec- ommendations for future research and practices are also given in the context of the paper. Ertas et al. [13] tested four types of ductile moment-resisting precast concrete frame connections and one monolithic concrete connection. The modified bolted connection showed the best performance in terms of strength, ductility, and energy dissipation in addition to ease and speed of construction. Three of the specimens could sustain up to 3.5% story drift. Kaya and Arslan [14] tested post-tensioned precast beam-to-column connections at different stress levels, and performed a series of analytical works by using ANSYS software. The results obtained from the analytical works are compared with the test results.

Parastesh et al. [15] proposed a joint type in which prefabri- cated concrete columns are cast continuously in the elevation with a free space in the connection zone to connect beam elements. Four diagonal bars are used in the empty zone of the precast columns to provide adequate strength and stability during the installation pro- cess. Flexural strength, ductility, strength degradation and energy dissipation capacity of the precast and monolithic connections are compared. While the precast connections provided adequate flexural strength, strength degradation and drift capacity, they exhibited considerably higher ductility and energy dissipation compared to similar monolithic specimens. Negro et al. [16] and Bournas et al. [17] presented the full-scale test results of three-storey precast building studied in the framework of the SAFECAST project. Dry mechanical connections were adopted to realize the several joints. The effect of two types of beam–column connections on the seismic behavior was evaluated. They were the pinned beam–column joints and a new connection system with dry connections. It was concluded that the new beam-to-column connection system is a viable solution toward enhancing the response of precast RC frames subjected to seismic loads, in partic- ular when the system is applied to all joints and quality measures are enforced in the execution of the joints.

The beam–column connections shown in Fig. 1 have been started to be used in Turkey for low-rise industrial and residential buildings. In spite of this fact, there is no experimental evidence for validation of the effectiveness of these connections under seis- mic actions. In order to have better insights to the matter, an experimental campaign has been initiated  as  part  of the SAFECAST, a European Commission FP7 funded research project focused on improving the seismic behavior of precast    structures.The tested sub-assemblages represent the exterior beam–col- umn connections of inner axes of the precast    buildings.

2. Description of specimens

Two different types of beam–column connections have been tested  at  Structural  and  Earthquake  Engineering  Laboratory   of Istanbul Technical University (ITU) as a partner of the SAFECAST. The connections are categorized as industrial type and residential type depending on the existence of corbels on the lower column, Fig. 2.

Dimensions of the industrial type connection are reduced in geo- metric scale of SL = 1/2 to fit the existing testing set-up. The simil- itude law are utilized in the determination of some parameters. The scale factors are (i) (SL) for length and displacement, (ii) (SL)2 for area and forces, (iii) (SL)3 for bending moment, (iv) (1.0) for stress and strain, Noor and Boswell [18]. And yet the residential type connections are produced in full   scale.