Improving the Seismic Performance of Braced Frames by Combining Pipe Damper and Steel Bars as Two-Stage Damper to Respond Effectively to large Deformation Under Seismic Loading
Year: 2026
Type: dissertation
Abstract: This study introduces an innovative passive damping system featuring a unique damper constructed by integrating steel pipes and bars into a fuse unit, which can be called Pipe-Bar Damper (PBD). This damper demonstrates impressive resilience to significant deformations, adeptly adapting to seismic levels while possessing a distinctive capability to efficiently dissipate seismic energy. In this study, the novel system is subjected to experimental testing within a single diagonally braced frame under cyclic loading. To evaluate the performance of this damper, three illustrative specimens were manufactured. Afterward, the three samples underwent testing under static cyclic loading in the lab. Multiple characteristics were assessed, encompassing ultimate and yield displacement, ultimate and yield strength, elastic stiffness, ductility, and failure mode. The new damper demonstrated consistent force-displacement hysteresis patterns, with all examined samples showing comparable behavior under both tension and compression. Additionally, the hysteresis loops were complete and devoid of any pinching. The experimental findings validate the expected multi-level functionality of the proposed damper, enabling effective energy dissipation across different force levels. The new damper demonstrated a relative drift of approximately 3.5% while maintaining its strength without any reduction. Moreover, this new system can achieve a ductility index exceeding 6.0. The samples with thicker pipe thickness exhibited the highest initial stiffness, whereas those with the greatest diameter of steel bars demonstrated the highest ultimate strength. When maintaining the pipe's thickness and diameter constant and increasing the diameter of steel bars by 1.25 times, an approximate 26% increase in ultimate capacity was observed. Furthermore, the new system was simulated using ABAQUS software, and the results were compared to experimental data, showing a good level of agreement. Finally, a parametric study was conducted to evaluate the influence of various geometric parameters on the performance of the PBD system. This study focused on the thickness of the pipes and the diameter of the bars. The findings from this parametric analysis revealed that the diameter of the steel bars had the most significant impact on the overall performance of the system. Variations in bar diameter led to notable changes in the damper’s behavior, highlighting the critical role this parameter plays in the of PBDs.
Source: Test
Language: Persian
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,190
OpenAlex ID: W7214715545