الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Studying coupled shear walls and coupling beams is of considerable importance in the field of structural engineering for resisting lateral loads and improving overall seismic performance with providing increased strength and ductility. The behavior of coupling beams is complex and as a result, it is essential to accurately predict their behavior when subject to high shear force demand. The present thesis addresses this challenge by examining the use of two different methods for the analysis of coupling beams that help improving overall seismic behavior of coupled shear walls. The first and main method used in this study is the strut-and-tie model, which is a powerful tool for analyzing the behavior of reinforced concrete structures under complex loading conditions. It is based on the flow of forces within the members of complex structures. The approach is widely used in almost all design building codes and introduced in this thesis for predicting the overall behavior of coupling beams in concrete construction. The other approach utilized in this study is the nonlinear finite element analysis using Abaqus program, which can provide detailed and accurate insight into the complex behavior of reinforced concrete coupling beams. It is capable of providing a comprehensive simulation of the behavior of the material and the geometry of the structure. Reinforced concrete coupling (or link) beams are usually cast integral with wall piers to help them act as a unit to resist lateral loads. The use of deep beam design provisions leads to conservative shear designs for link beams which do not follow Euler-Bernoulli beams. Instead, strut-and-tie systems are used. The thesis demonstrates the modeling of such beams using strut-and-tie provisions. Alternatively, to using a time-consuming trial-and-error process, a unified general multi-panel strut-and-tie model is proposed, and simple design equations are developed to directly design conventionally reinforced link beams subjected to high shear force demand. As link beams have often a small span-to-depth ratio, the first one- and two-panel strut-and-tie models are considered basic and common. The one-panel model consists of a direct inclined compression concrete strut with horizontal tension ties in addition to the required crack-control web reinforcement and is used wherever the strut-tie angle is greater than the minimum of 25 degrees; one vertical-to-two horizontal. The two-panel model is used when the beam span is too long to use the one-panel model and consists of one vertical tension tie and two steep inclined compression concrete struts. Worked design examples have been presented to justify and demonstrate the ease of implementation of the considered first two simple and direct models of the proposed unified general multi-panel strut-and-tie model. The predictions of the two basic models have been compared with sample calculations and the comparison shows a good agreement. ”