## 1 Introduction
(2018) performed shake table tests on BRBs to investigate their out-of-plane stability. [PERSON] et al. [PERSON] et al. (2019) performed sinusoidal deformation tests on full-scale five-story buildings with dampers by using a shaking table. [PERSON] (2010) conducted five buckling-restrained braced frame (BRBF) tests under cyclic loading. During these tests, local buckling of BRBs occurred at a drift ratio of 1.5%. [PERSON] et al. [PERSON] et al. (2011) and [PERSON] and [PERSON] and [PERSON] (2012) tested a full-scale three-story three-bay BRBF by using a pseudo-dynamic testing method. Furthermore, [PERSON] (2013), [PERSON] and [PERSON] and [PERSON] (2014), and [PERSON] et al. [PERSON] et al. (2015) examined the strengthening of deficient reinforced concrete (RC) frames with BRBs. [PERSON] et al. [PERSON] et al. (2016) tested 8.5 m and 3 m BRBs under axial compression and tension demands to investigate the effects of their yield length on the energy dissipation capacity. They concluded that BRBs with shorter yield lengths have higher energy dissipation capacity compared to those with longer ones. [PERSON] et al. [PERSON] et al. (2017) carried out the brace and subassembly tests of tube-in-tube BRBs consisting of circular and square CPs, tube CM, and infill polymer to investigate their capability of stability and inelastic deformation. A bare frame and a BRBF were tested under cyclic loading by [PERSON] et al. [PERSON] et al. (2018). They observed that the BRBs improve the lateral resistance, initial rigidity, and energy dissipation capacity of frames. As can be understood from the recent literature, the behavior of BRBF has yet to be fully understood ([PERSON] et al., 2018; [PERSON] et al., 2019; [PERSON] et al. the effects of pre-tension load on the bolts of slip-critical connections in the steel frame and the friction between the contact surfaces of the steel plates on the numerical behavior of the BRBF. Moreover, conducting experimental studies to understand the structural behavior of BRBF can be prohibitive due to their high cost. However, carrying out FE studies with validated physical tests can reduce the cost and time, together with considering different parameters that affect structural behavior. It is therefore required to develop a proper FE model to predict the hysteretic behavior of BRBF. This paper also offers an FE model accurately predicting the behavior of BRBF. The aim of this paper is to both experimentally and numerically investigate the behavior of BRBFs. The BRBF specimen was tested under the reversed cyclic loading protocol. The BRB specimen used in the steel frame had identical properties to the BRBs tested by [PERSON] et al. [2]. An FE model was developed by using the Abaqus software [39] and validated to conduct further parametric research. A numerical parametric study was first conducted on three BRBs [2] to calibrate material used for the CP and the friction coefficient between the CP and the CM. This was followed by a numerical parametric study carried out on the steel frame with a slip-critical connection to determine the friction coefficient between contact surfaces of steel plates of slip-critical connections. The pretension load for bolts was taken as 110 KN in accordance with the Turkish Steel Code (TSC) [43]. The numerical hysteretic behavior of the BRBF was last parametrically investigated using the calibrated values for the BRB and steel frame obtained from the first and second phases of the FE study.