Seismic Evaluation Using Non-Linear Time History Analysis
No Thumbnail Available
Date
2018-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
AAU
Abstract
A building subjected to earthquake is expected to show inelastic behavior that the
deformation in a member does not remain proportional to the internal force. A non-linear
analysis accounts for the inelastic response. Both material non-linearity and geometric
non-linearity case considered. There is plastic deformation and energy absorption in a
member for higher levels of internal force. This type of nonlinear behavior is referred to as
material non linearity. Several different hysteresis models are available to describe the
behavior of different types of materials. For the most part, these differ in the amount of
energy they dissipate in a given cycle of deformation, and how the energy dissipation
behavior changes with an increasing amount of deformation. Pivot hysteresis model is
used.
This thesis work uses fifteen story and two basement building of 40/60 project of City
Government of Addis Ababa Saving House Enterprise as a case study. A comparison is
made between linear elastic analysis and non-linear time history in-terms of story
Displacement, Inter-story drift, story Shear, Axial force and Torsion. Thus it should not be
surprising that buildings suffer damage during intense ground shaking. The main focus of
this work is to evaluate the seismic resistance by using non-linear time history analysis so
that the damage will be controlled to an acceptable degree.
Seismic input to nonlinear dynamic analyses of structures is usually defined in terms of
acceleration time series. Three references Earthquake Ankober 2016, EL-Centro 1940 and
Sierra-madre 1991 is used to generate artificial time history using time-domain method.
The time domain method is generally considered a better approach for spectral matching
since this method adjusts the acceleration time histories in the time domain by adding
wavelets.
The major advantage of using the forces obtained from a time history analysis as the basis
for a structural design is that the vertical distribution of forces may be significantly
different from the forces obtained from an equivalent static load analysis.
Description
Keywords
Non-Linear Time History Analysis, geometric non-linearity