Abstract

Posttensioned connections for steel moment resisting frames (MRF) can reduce residual deformations through self-centering capabilities. Devices are added to improve the connections energy dissipating capability and includes energy dissipating (ED) bars, friction dampers, and steel angles located at the top and bottom of the beam-to-column connections. The Post-Tensioned Energy dissipating (PTED) connection reduces inelastic deformation to the beams and columns, is installed with minimum welding, displays self-centering thus reducing residual deformations, and allows for easy replacement of the ED devices. An inerter is a two-terminal mechanical device that generates a force proportional to the relative acceleration between its nodes. The inerter dampens structural responses, inter-story drift, and vibration by simulating a mass element; the mass of an inerter is very small. The inertance is a constant of proportionality that illustrates the simulated mass of the device. This Thesis aims to reduce residual drift by comparing the different PTED connections and the inerter. Three PTED models utilizing either ED bars, friction dampers, or steel angles as ED devices are created using the finite element software OpenSees. Each model is subjected to eleven different earthquakes and the structure responses are compared to a typical welded moment resisting frame (WMRF). Results indicate that the seismic performance of PTED connections exceed that of the WMRF. Each PTED model is re-subjected to the eleven earthquakes with the addition of the inerter. The responses are compared to the WMRF and the PTED models that do not include the inerter. Models utilizing the inerters exhibited better seismic performance than the WMRF and PTED models that did not have the inerter. Optimization of the PTED connections with and without the inerter is conducted by using a genetic algorithm that focuses on parameters of the ED devices and posttensioned strands. Furthermore, the genetic algorithm revealed that uniform parameters, that is the external and internal calculations having the same parameters, on a given story is the optimal design in all but one connection. The optimal solution is the PTED connection utilizing friction dampers and inerter which displayed the lowest residual drift.

Notes

If this is your thesis or dissertation, and want to learn how to access it or for more information about readership statistics, contact us at STARS@ucf.edu

Graduation Date

2022

Semester

Summer

Advisor

Apostolakis, Georgios

Degree

Master of Science (M.S.)

College

College of Engineering and Computer Science

Department

Civil, Environmental and Construction Engineering

Degree Program

Civil Engineering; Structures & Geotechnical Engineering

Identifier

CFE0009150; DP0026746

URL

https://purls.library.ucf.edu/go/DP0026746

Language

English

Release Date

August 2023

Length of Campus-only Access

1 year

Access Status

Masters Thesis (Open Access)

COinS