الفهرس 
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Abstract
This research presents a comprehensive study to perform the seismic analysis of buildings using Direct Displacement Based Method (DDBM), which is a viable and logical alternative to current force-based code approaches. This method is based on a concept of designing structures to achieve a specified performance limit state defined by strain or drift limits.
The main objective of the paper is to examine analytically the use of DDBM in seismic design of different types of structural systems (frame, wall, and dual wall-frame buildings) and compare it with the traditional Force Based Design Method (FBDM). Using a developed Excel spread sheets for DDBM procedure, a set of buildings with different heights (2, 4,6,8,10,12,14,16,18, and 20 stories) and different structural systems (frame buildings, wall buildings, and dual wall-frame buildings) are analyzed and the results are compared with those of (Force Based Design Method) FBDM modeled using computer programs SAP and ETABS. This comparison proved that Direct Displacement Based Method is more reliable as it is based on a secant stiffness (rather than initial stiffness) representation of structural response, using a level of damping equivalent to the combined effects of elastic and hysteretic damping. This design method is extremely simple to apply and is very successful in providing dependable and predictable seismic response.
Objective of the Present Investigation
The objective of the present thesis is to develop DDBD for buildings to verify its reliability, applicability and effectiveness against the force-based traditional code time history analyses for the assessment of the structural response.
Scope
The first chapter of the research is an introduction describing a general view of performance based design method and the objectives of that thesis and also provide detailed contents of that research.
Second chapter is a literature review of the previous researches that worked on understanding the behavior of structures designed by FBD and its defects and why the designers searched for other method of design method which depends on performance of structures until reaching to direct displacement design method.
In the third chapter, we provided the DDBM rules and design procedure throughout three solved examples of different types of buildings frame buildings, wall buildings and dual wall/frame building showing the DDBM mathematical formulas of each type. And also for facilitating our DDBM modeling we developed an EXCEL spread sheets for each type of buildings that can solve wide range of parameters and inputs of the studied buildings and also can perform data tables and draw displacements, shear distribution and overturning moment charts.
In the fourth chapter of thesis a verification of our modeling procedure in the used analysis programs ETABS and SAP which are widely used by the designers to be sure that our results are on high accuracy. And for that aim we used a solved design Eurocode example and by comparing results we found the best procedure of modeling. Another practical frame Eurocode which is solved by time history data also used in verification the modeling method and the results are presented which confirm and improve our modeling method.
In the fifth chapter a selected evaluated buildings of different heights from 2 to 20 stories and of different types of buildings (frame, wall, and wall/frame building) modeled using ETABS and SAP computer programs are illustrated in details and their geometry, acting loads and deformation shape also the method of their modeling step by step is presented.
In the sixth chapter results of modeling of different types of buildings building using the two different methods “FBDM modeled by SAP and ETABS programs” and “DDBM modeled by developed Excel sheets” are presented in clear charts and tables to perform a comparison between the two methods in seismic analysis.
Seventh chapter illustrates the conclusions of the comparison between DDBM and FBDM seismic analysis indicating the best method for different types of buildings and for different heights and at the end of that chapter the recommendations for the future for the next researchers.