An innovative passive metallic damper with replaceable components for earthquake protection of structures

Aghlara, Reza

An innovative passive metallic damper with replaceable components for earthquake protection of structures

dc.contributor.author	Aghlara, Reza
dc.date.accessioned	2023-09-10T01:52:37Z
dc.date.available	2023-09-10T01:52:37Z
dc.date.issued	2019
dc.description	Thesis (PhD. (Civil Engineering))
dc.description.abstract	Metallic yield dampers dissipate earthquake energy imposed on structures by yielding their components. Since energy dissipation is emphasised in such dampers and their replaceability after failure has been considered relatively low from a practical point of view, this research proposed a new metallic damper, namely Fuse Damper (FD), to overcome the mentioned drawback. By using this proposed device, the seismic energy is dissipated through replaceable components which are used as sacrificial elements. The FD is made of steel components that are commonly used in engineering structures, and therefore, does not require any advanced technology or experts. The general aims of this study were, firstly to evaluate the performance of the FD in real scale with three types of replaceable elements, namely steel bars, bare steel pipes and tin-filled steel pipes, individually using cyclic and monotonic tests, and subsequently to investigate the influence of the FD on the behaviour of a typical brace numerically. The effect of the size and dimension of fuses were experimentally evaluated based on hysteretic behaviour, energy-absorbing capacity, and equivalent viscous damping ratio of the FD. Finite element models of the specimens were developed and calibrated using experimental results. The models were extended for parametric studies to derive key formulas for the mechanical properties related to the FD with steel bars and pipes. In the final step, a typical brace equipped with a bar-fuse damper (BFD) was numerically studied under different load conditions. As an important finding, all used fuses were repeatedly replaced with new ones after each failure in the experiments, thus revealing the replaceability feature of the FD. The results showed that both bars and pipes had the highest force-to-mass ratio among the existing metallic dampers, which indicated the material efficiency of the fuses in the FD. In addition, the results also revealed that taking the target displacements of the FD by less than 13 and 5.5 % of the length of the steel bars and pipes, respectively, would fulfil at least 20 endured hysteretic cycles defined by FEMA 461, without compromising on either strength or stiffness. Also, the experimental hystereses of both tin-filled pipes and bare-pipes fuses showed that filling pipes with tin metal did not significantly improve the performance of the FD. Moreover, the study of a typical brace with the BFD demonstrated that the proposed device promoted the behaviour of the brace by increasing its capacity for energy dissipation and prevented it from buckling. The findings of this study indicate that, the use of the FD with replaceable steel and pipe fuses may have the potential for improving the seismic responses of structures.
dc.description.sponsorship	Faculty of Engineering - School of Civil Engineering
dc.identifier.uri	http://openscience.utm.my/handle/123456789/710
dc.language.iso	en
dc.publisher	Universiti Teknologi Malaysia
dc.subject	Earthquake resistant design
dc.subject	Structural design
dc.subject	Energy dissipation
dc.title	An innovative passive metallic damper with replaceable components for earthquake protection of structures
dc.type	Thesis
dc.type	Dataset