الفهرس 
CHAPTER 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
Structural analysis of buildings under effect of thermal expansion/contraction is an integral part of the overall analysis process for designers. In thermal analysis, the high axial stiffness of the building floors can produce relatively large lateral forces on the supporting columns. This effect is more pronounced in case of buildings of large lengths, and when high-stiffness elements such as shear walls, or cores exist at the building edges. For RC floors, the existence of flexural cracks can reduce this high axial stiffness. The aim of this study is to investigate the effect of these cracks on the axial stiffness of flat slabs, with the objective of making an assessment of suitable reduction factors to be applied to the slabs axial stiffness to be considered in analysis, in both cases of floor compression and tension under effect of thermal loading.
An analytical algorithm is developed for computation of a realistic value for the cracked stiffness of flat slab sections at specific values of bending moment and axial force acting on them. This algorithm is applied into the development of a software package, utilized for analysis of flat slabs under thermal loads, and to determine the values of axial stiffness reduction factors to be applied in analysis through an iterative process.
Application of the developed algorithm to several cases of actual buildings analysis is extended to include the effect of various parameters, such as building length, slab section and reinforcement, and the existence of shear walls of varying stiffnesses near the building edges. Results of the study are used to provide designers with realistic values for axial stiffness reduction factors to be applied in analysis. The results are compared to current code specification, and recommendations are presented in this regard.