PSI - Issue 64

Nouraldaim F.A. Yagoub et al. / Procedia Structural Integrity 64 (2024) 105–113 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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post-tensioned strands, and thickness of the flexural energy dissipator device. Additionally, a finite element model of the proposed system was developed using the ABAQUS platform, and its accuracy was verified through simulation. The findings demonstrate that the proposed system exhibits a typical "double-flag shape" hysteretic response, indicative of excellent seismic resilient functionality.

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b

side view

Front view

Front view

side view

Fig. 2. Front and side view of: (a) Flexural plate ED and (b) steel wall toe.

Fig. 1. Schematic representation of seismic resilience (Xu et al., 2023b). . a b

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Fig. 3. Self-centring precast wall: (a) The reinforcement and dimensional details of test specimens, (b) Replaceable flexural plate, and (c) Finite element model.

2. Reference wall system description and material properties The reinforced concrete post-tensioned precast concrete wall system denoted as HW1(Lu and Wu, 2017)integrates a combination of prestressing tendons (PT) and mild energy dissipation (ED) steel reinforcement. Figure 3a presents the dimensions and reinforcement details of wall system HW1, while Table 1(Lu and Wu, 2017) delineates the reinforcement specifics of the test wall. The wall stands at a height of 3.2 m, with a length of 1.6 m and a thickness of 0.2 m. Lateral loading is applied to the top loading beam of the wall, positioned 3.5 m from the base. Longitudinal reinforcing rebars, Grade HRB400 (per GB 50010-2010), equipped with 8 mm closed hoops spaced at 80 mm intervals, fortify the structure. The quantities of PT and ED mild steel were calibrated to offer comparable resistance. In this study, HW1 wall system reinforcement comprises three 15.2 mm PT strands to bolster self-centering, alongside eight 18 mm Grade 400 rebars serving as ED mild steel. To prevent strain concentration, all PT strand wraps around the base panel span 400 mm. Initial stresses in the PT strands of post-tensioned models are set at 0.4f ptk , where f ptk represents the nominal strength of each strand (1860 MPa). Vertical axial stress exerted on the test wall amounts to 1000 kN. The external flange thickness measures 35 mm, providing additional load-bearing capacity and minimizing deformation during pressure on wall toes, thus averting damage. The FPED design for HW1, depicted in Figure 3b, comprises a semicircular top web, a vertical front flange at the opening, a rear flange at the closure, and a bottom plate. Steel wall toes secure the vertical front flange and bottom plate of the opening, while the bending FPEDs are housed within steel wall toes, conserving building space. Wall panels of the reinforced concrete post-tensioned precast concrete wall system HW1 are vertically assembled using PT strands. Concrete, steel reinforcement, and PT steel properties pertinent to wall system HW1 are listed in Table 2 (Lu and Wu, 2017). Normal-weight concrete, with a measured cylinder compressive strength of 30.2 MPa on the test day, is employed for HW1.