الفهرس 
LITERATURE-REVIEWOnly 14 pages are availabe for public view
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Abstract
Reinforced concrete structural shear walls (RC Walls) have been recognized as the main effective lateral force resisting systems which have the ability to confer good performance on structures subjected to earthquakes and wind. Their high stiffness can decrease or completely avoid damage to nonstructural components, and sufficient strength can be provided to resist moderate and strong ground shaking with just limited structural damage.
Often, as result of the other engineering disciplines requirements, the implementation of openings in shear walls arises. The effects of these openings are usually neglected when their sizes are relatively small compared to the wall dimensions. But, in the case when these openings are relatively large or located within a critical region, they may significantly influence the seismic behavior of RC walls.
Hence, studying these openings is very important to clarify their effect on the response modification factor (R). The influence of the opening dimension, width height, and area on the value of the response modification factor (R) was investigated numerically.
An investigation has been carried out for two models first, a 2-storey RC Frame which experimented by Vecchio, F., & Emara, M.(1992) and verified numerically by Serhan Güner (2008) has been modelled using ETABS and SAP2000 software second, 8-storey Dual System building which studied by Ibrahim Yasser et al. modelled using both SAP 2000 and ETABS software.
A numerical study has been conducted on four reinforced concrete models consisted of eight-storey and have 5 bays for both X and Y directions. The seismic load resisting system consists of dual system shear walls and frames, whereas the gravity load carrying system comprises Concrete flat slab supported by RC columns and shear walls. The four buildings have been well designed according to the Egyptian code. A numerical study has been conducted to evaluate (R) factor before and after applying openings with different dimensions. In case of applying openings, Lintel beam has been defined the as a spandrel, wall segment and putting additional steel around openings.
Pushover analysis has been conducted and pushover curve has been plotted which used to calculate the response reduction / modification factor parameters (ultimate displacement, yield displacement and yield base shear) and evaluate (R) factor after plotting the pushover curve by using three different methods Acceptance Criteria Limits for Hinges Deformation, Park Definition for Ultimate and Yield Deformation, and ASCE 41-13 Idealized Bilinear Curve.
Some degradation was observed in base shear related to the same displacement while opening conducted. This reduction increased by increasing the opening size. To improve the system performance half of reinforcement bars terminated to conduct openings has been added on either side of the opening which case some increasement in the response reduction factor up to 12% for the studied cases. The calculated value of R-factor is smaller than the stated value of R-factor for limited ductility class of RC dual system consists of (MRF) Moment Resistant Frame and (SW) Shear Walls structures with opening at ECP-201(2012) which should be adjusted to the value utilized in Eurocode-8 (2004).
Keywords: Response Reduction / Modification Factor (R) – Pushover analysis – Nonlinear static analysis – Shear walls with openings – Spandrel – Coupled wall