Coupled Systems Mechanics, Vol. 7, No. 6 (2018) 731-753 DOI: https://doi.org/10.12989/csm.2018.7.6.731 731 Copyright © 2018 Techno-Press, Ltd. http://www.techno-press.org/?journal=csm&subpage=8 ISSN: 2234-2184 (Print), 2234-2192 (Online) Effects of numerical modeling simplification on seismic design of buildings Shehata E Abdel Raheem *1, 2a , Mohamed Omar 3, 4b , Ahmed K Abdel Zaher 1, 5b and Ahmed M Taha 1b 1 Faculty of Engineering, Taibah University, Madinah 41411, KSA 2 Civil Engineering Department, Faculty of Engineering, Assiut University, Assiut 71516, Egypt 3 Civil Engineering Department, Faculty of Engineering, Aswan University, Egypt 4 Civil Engineering Department, Faculty of Engineering Rabigh Branch, King Abdulaziz University, KSA 5 Civil Engineering Department, Faculty of Engineering, Cairo University, Giza, Egypt (Received July 4, 2018, Revised September 27, 2018, Accepted October 20, 2018) Abstract. The recent seismic events have led to concerns on safety and vulnerability of Reinforced Concrete Moment Resisting Frame “RC-MRF” buildings. The seismic design demands are greatly dependent on the computational tools, the inherent assumptions and approximations introduced in the modeling process. Thus, it is essential to assess the relative importance of implementing different modeling approaches and investigate the computed response sensitivity to the corresponding modeling assumptions. Many parameters and assumptions are to be justified for generation effective and accurate structural models of RC-MRF buildings to simulate the lateral response and evaluate seismic design demands. So, the present study aims to develop reliable finite element model through many refinements in modeling the various structural components. The effect of finite element modeling assumptions, analysis methods and code provisions on seismic response demands for the structural design of RC-MRF buildings are investigated. where, a series of three-dimensional finite element models were created to study various approaches to quantitatively improve the accuracy of FE models of symmetric buildings located in active seismic zones. It is shown from results of the comparative analyses that the use of a calibrated frame model which was made up of line elements featuring rigid offsets manages to provide estimates that match best with estimates obtained from a much more rigorous modeling approach involving the use of shell elements. Keywords: MRF buildings; codes provisions; seismic design demands; finite element modeling; modeling assumptions 1. Introduction Through the recorded history, many earthquakes had occurred; damaged buildings and led to Corresponding author, Professor, E-mail: shehataraheem@yahoo.com a Professor b Assistant Professor, E-mail: moh_omar77@yahoo.com or dr.ahmedkamal@hotmail.com or amtaha@taibahu.edu.sa