الفهرس 
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Abstract
Nonlinear cyclic response of reinforced concrete structures containing shear walls under seismic action falls mathematically in the area of dynamic analysis that is an intricate job. The spectral modal linear analysis is the most common in seismic analysis but it is not strict for the nonlinear behavior of reinforced concrete structures. However, using the quasi-static nonlinear cyclic finite element analysis reduces the complexity of the dynamic analysis, overcomes the error in estimating the damping forces, and allows for using recent models developed according to extensive test data rather than models based on empirical equations. Although many finite element programs are available for the nonlinear analysis of reinforced concrete structures they have many limitations and it was reported that, more efficient finite element algorithms are required to reduce storage capacity and calculation time. Hence, the purpose of this thesis is to develop a more elaborated computer program (EGY-NLFEA) for analyzing reinforced concrete structures under monotonic as well as cyclic loading conditions. This was achieved by implementation of the disturbed stress field model into nonlinear finite element algorithm for static monotonic loading, and then extending the algorithm to reversed cyclic quasi-static analysis, by the use of recently developed cyclic material models. The advanced skyline and the incompatible displacement techniques were also used in favor of fast calculations and reduced storage requirements. Furthermore, the program was designed to perform linear as well as nonlinear analysis, be the core for complete finite element package by easily accepting new additions to its library without disturbing the main routines, and accept graphical interface. It was verified that EGY-NLFEA could predict the response of different reinforced concrete structures accurately under monotonic loading without any limitations on the structure size. Factors affecting the nonlinear finite element analysis results are discussed. Effects of shear-wall properties on the behavior of the multi-story frame-shear wall systems are also introduced. It was concluded that; Introducing the incompatible displacement modes to the disturbed stress field model leads to significant improvements to the predicted response of reinforced concrete structures in flexure, Design of multi-bay frames using the concept of equivalent frame leads to significant reduction in calculations with considerable accuracy, The response under reversed cyclic loading can be predicted up to yielding of steel or crushing of concrete As a result of numerical problems encountered “at high levels of stress reversals” using the total secant stiffness approach in the quasi-static nonlinear reversed cyclic analysis of reinforced concrete structures requires re-examination.