Umudike Journal of Engineering and Technology

Michael Okpara University of Agriculture, Umudike


DYNAMIC RESPONSE OF MULTI-DEGREE OF FREEDOM FRAMES SUBJECTED TO IDENTICAL SUPPORT EXCITATION DUE TO EARTHQUAKE

Ezeokpube, G. C.
Department of Civil Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B 7267 Umuahia 440109, Abia State, Nigeria

Nnadi, E.
Department of Civil Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B 7267 Umuahia 440109, Abia State, Nigeria



ABSTRACT

This paper presents the dynamic response of multi-degree of freedom frames subjected to identical support excitation due to earthquake using the Finite Element method. A finite element displacement model was developed for the analysis under prescribed ground acceleration and maximum ground displacement of 0.74g and 0.015m respectively. The equation of motion for frames under prescribed identical support ground motion was derived using the lumped mass parameter, static condensation and Finite Element method. Solution of the system gives the natural frequencies, joint displacements and the internal stresses of the flexible frame. A MATLAB code was developed for numerical solution. The developed MATLAB code was used to carry out parametric studies on the various values of ground acceleration ranging from 0.74g-0.3g and for the maximum ground displacement ranging from 0.008m-0.015m. The present work established that (a). Joint displacement increases with increase in maximum ground displacement. (b). forcing frequency increases with increase in ground acceleration and decreases with increase in maximum ground displacement. (c). Decrease in maximum ground displacement causes substantial decrease in the bending moments and should be encouraged in the economic design of framed structures. In conclusion, this work is recommended for the analysis of multi-degree of frames subjected to identical support excitation due to earthquake.


Keywords: Static Condensation; Ground Motion; Finite Element Method; Lumped Mass Procedure; MATLAB


View: 142 | Download: 2

Conference Code
IECON2019

Conference Title
ENGINEERING FOR SUSTAINABLE ECONOMIC DIVERSIFICATION, FOOD AND NATIONAL SECURITY

ISBN
978-978-53175-8-9

Date Published
Friday, September 20, 2019

Conference Date
2nd - 4th September, 2019

The contents of the articles are the sole opinion of the author(s) and not of UJET.


Open Access
Umudike Journal of Engineering and Technology makes abstracts and full texts of all articles published freely available to everyone immediately after publication thereby enabling the accessibility of research articles by the global community without hindrance through the internet.

Indexing and Abstracting
We are index in Google Scholar, AJOL, and EBSCO.