الفهرس 
CHAPTER (1): IntroductionOnly 14 pages are availabe for public view
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Abstract
The use of composite construction has become more widespread in recent decades as a result of combining the advantages of steel and concrete materials. Steel-concrete composite columns are extensively used in modern buildings. Extensive researches on composite columns have been carried.
Steel-section encased in reinforced concrete column is a combination of concrete, structural steel and reinforcing steel to provide an adequate load carrying capacity of the member. Composite columns are commonly used in tall buildings due to their high strength, full usage of materials, high stiffness and ductility, toughness against seismic loads and significant savings in construction time. Composite columns can be concrete encased steel or concrete-filled steel sections. This Thesis investigates the behavior of pin-ended axially and eccentrically loaded concrete encased steel composite columns. This thesis is composed of structural design, experimental test and numerical analysis on concrete encased cold formed steel composite column composed of steel. It focuses on determination and verification of load-carrying capacity with regards to design principles given by various codes specifications for design of steel and concrete composite columns. A proposed M-N interaction equation and evaluation of flexural rigidity are introduced in this thesis. The experimental program carried out on columns tested under uniaxial compression load and columns tested under uniaxial compression load combined with bending moment under two parameters, the slenderness ratio, load eccentricity effect in two directions and axis of bending; major or minor.. A total of thirteen specimens have been tested experimentally until failure. The failure characteristics of such columns were investigated considering ultimate load capacity, failure mode and location of failure zone, load mid-displacement relationship, and effect of load eccentricity. Based on the experimental test results, the strength of columns were assessed according to the provisions of Egyptian Code of Practice for steel construction, ECPS-LRFD 205-2007 [1], Euro-Code 4 (EC4) [2], Load and resistance factor design method (AISC-LRFD) [3], American Concrete Institute Standard (ACI 318-14) [4], and Canadian Standard Association and CSA-A23.3-04 [5]. A Finite element model using ABAQUS/CAE [6] was developed. It takes into account both material and geometrical non-linarites. Results from the experimental program were used to verify the proposed finite element model. Finally, an analytical provision was carried out on the composite column design to be used in the Egyptian Code of Practice for Steel Construction.