This document summarizes a thesis that compared different methods for analyzing reinforced concrete structures under static and seismic loads. The thesis analyzed three buildings using different analysis methods and combined the resulting forces in three ways specified by Eurocode 8. It designed selected columns based on the combined forces and compared the reinforcement requirements. The comparison of results led to conclusions about analysis methods and ways of combining forces.

1. Comparative Assessment of Reinforced Concrete Structures Analysis Methods
Abstract
The way that the axial force and the moment forces about X and Y axes are combined when a building is being
analyzed under static and seismic response by a structural analysis program is a major matter of discussion
concerning dynamic analysis of structures. There are different ways in which these three forces can be
combined in order to proceed to the designing of a section, different ways of combination might lead to
distinctively different reinforcement necessities. The aim of the thesis is to clarify the existing ways of
combination of the three forces N, Mx, My, to evaluate and to compare the results of their application.
The first part of the thesis includes research concerning the way that static and dynamic forces are being
combined by the structural analysis program SAP2000. The research clarifies the wrong way the program
combines the above mentioned forces despite the user’s definition of the combinations. Taking this into
consideration, three different buildings are being simulated and analyzed. These are the S.P.E.A.R. building
located in the laboratory of E.L.S.A. in Ispra of Italy, a two axes symmetrical building with reduced stiffness as
far as height is concerned and a third building which includes asymmetric column sections of “Γ” shape in its
corners. The three buildings are being analyzed using Modal Response Spectrum Analysis, Lateral Force Method
of Analysis and Elastic Time History Analysis where the inelastic design spectrum is defined as the target spectra.
The results of the forces due to gravity load and seismic load are being combined in the three ways proposed by
Eurocode 8. The resulting forces are used for the designing of selected columns. The reinforcement necessities
from the above mentioned ways are being compared and by the results of this comparison conclusions are
being arisen regarding the methods of analysis and the ways that forces are combined.
In conclusion, the thesis was oriented by the uncertainty around the specific topic analyzed above. In order to
complete this task critical thinking and superior computing were required. The successful completion of the
thesis led to clear and specific results.