Torsional hysteretic damper for seismic protection of structures

Download

index.pdf

Date

2014

Author

Salem Milani, Ali

Metadata

Show full item record

Item Usage Stats

287
views

169
downloads

During the past decades, use of supplementary systems for seismic control of structures has gained increasing acceptance, and research has flourished on development and performance characterization of such systems. These include isolation systems and energy dissipation devices (dampers). This study is devoted to development of a new hysteretic damper for seismic protection of structures. The new system is a stand-alone damper, named Multi-directional Torsional Hysteretic Damper (MTHD). MTHD is composed of eight energy dissipaters in the shape of a cylinder with enlarged top and bottom. The cylindrical dissipaters are designed to yield in torsion created in them via arms while being supported against bending by a stiff central column. MTHD is capable of large force and displacement capacities, can be coupled with various types of bearings due to its 2-part configuration (upper rail system and lower base device) and shows a variable and controllable-via-design post-elastic stiffness. The new damper has gone through many stages of design refinement, prototype verification tests and development of computer codes to facilitate its implementation in practice. Practicality of the new device, as an offspring of an academic sphere, is assured through extensive collaboration with industry in its final design stages, prototyping and verification tests. The scope of this research includes all developmental phases of the MTHD device, including conceptual design, analytical and numerical studies and verification tests. The experimental part of the study is comprised of two phases: verification tests on a prototype MTHD, and a series of torsional low-cycle fatigue tests on cylindrical steel specimens. Torsional low-cycle fatigue tests were aimed at studying the fatigue performance of the cylindrical energy dissipaters of MTHD and to use the data in cyclic strain-life design.

Subject Keywords

Earthquake resistant design., Buildings, Buildings, Torsion.

URI

http://etd.lib.metu.edu.tr/upload/12617261/index.pdf
https://hdl.handle.net/11511/23536

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Investigation of seismic isolation efficiency for building structures Özdemir, Seda; Yakut, Ahmet; Ay, Bekir Özer; Department of Earthquake Studies (2016) The main goal of this study is to assess the efﬁcacy of seismic isolation for building type of structures with different structural systems, namely, dual systems and moment frame systems having also different number of ﬂoors. Speciﬁc to this study, the main parameters employed for efﬁcacy assessment will be the interstorey drift ratio and ﬂoor acceleration since both structural and non-structural damage to be occured in a system are directly related to these two parameters. To assess the variations in inter...
Frequency domain optimization of dry friction dampers used for earthquake vibration damping of buildings Erişen, Zühtü Eren; Ciğeroğlu, Ender; Department of Mechanical Engineering (2012) There are many active and passive vibration control techniques to reduce the effect of energy on structures which emerges during an earthquake and reduce the displacement of buildings that is caused by ground acceleration. Main advantage of passive vibration control techniques over active vibration control techniques is; no external power or a sensor is required for passive vibration control devices (PVCDs) and it results in lower installation and maintenance costs. However, PVCDs require a predefined optim...
Assessment of nonlinear static (pushover) analysis procedures using field experience Dilsiz, Abdullah; Gülkan, Polat; Yakut, Ahmet; Department of Civil Engineering (2013) Recently, many nonlinear analysis procedures have been proposed for earthquake response determination of the structures. Although, the nonlinear response history analysis (NRHA) is accepted as the most accurate source of information for nonlinear seismic response, nonlinear static procedures (NSP) may also provide reasonable estimates of seismic demand and inelastic behavior. However, all proposed NSPs have limitations, due to the certain approximations and simplifications, such as invariable load pattern a...
Inelastic panel zone deformation demands in stell moment resisting frames Tuna, Mehmet; Topkaya, Cem; Department of Civil Engineering (2012) Panel zone is one of the significant parts of beam-column connections in steel structures. Until the 1994 Northridge Earthquake, a few experimental research and parametric studies had been carried out to understand the behavior of the panel zones. However, after the Northridge Earthquake, it was observed that beam-column connections were unable to show presumed seismic performance. Therefore, current design codes needed to be revised to improve seismic performance of connections in general and panel zones i...
Optimum design of multistep spur gearbox Öztürk, Fatih Mehmet; Department of Mechanical Engineering (2005) Optimum design of multistep gearbox, since many high-performance power transmission applications (e.g., automotive, space industry) require compact volume, has become an important interest area. This design application includes more complicated problems that are not taken into account while designing single stage gear drives. Design applications are generally made by trial and error methods depending on the experience and the intuition of the designer. In this study, using Visual Basic 6.0, an interactive p...

Citation Formats

A. Salem Milani, “Torsional hysteretic damper for seismic protection of structures,” Ph.D. - Doctoral Program, Middle East Technical University, 2014.