Date of Award

1-1981

Degree Type

Thesis

Degree Name

Master of Engineering (ME)

Department

Civil Engineering and Engineering Mechanics

Supervisor

A.C. Heidebrecht

Abstract

In seismic analysis of buildings it is usual to consider planar models along each of the two principal axes, and to independently analyze the response of each model to the in-plane horizontal component of ground motion. Analysis on this basis is strictly valid only for structures with coincident centers of mass and rigidity. The lateral and torsional motions are coupled if the centers of mass and rigidity do not coincide.

It is the purpose of this thesis to consider the torsional effect in the seismic analysis of one-story buildings and to illustrate the effect of the lateral-torsional coupling on their response.

A mathematical model for a torsionally coupled one-story building is developed considering the effect of eccentricity between the center of mass and the center of resistance. The coupled analysis is then investigated for excitation due to several different earthquakes.

The second object of this study is to develop a simple procedure, which provides a convenient means to obtain conservative estimates of earthquake forces in a special class of torsionally coupled systems.