Composite Columns Are In An Increased Usage For Construction Of HighrisernAnd Medium-Rise Buildings, Bridges And Other Structures. However,rnTheir Designs Involves Tiresome Calculations And Drawing Of InteractionrnCharts. In Addition, The Results Are Approximate. This Thesis PresentsrnDesign Aids For Concrete-Filled Steel Tubes To Simplify The Design And AtrnThe Same Time Increase The Accuracy Of Results. It Also SummarizesrnImportant Behaviors Of Concrete-Filled Tube Columns As Compared TornOther Column Types.rnGeneral Approaches Have Been Presented On How To Prepare DesignrnCharts And Such Charts Have Been Drawn For Selected Cross-SectionalrnShapes. Uniaxial Charts Have Been Drawn For Square, Rectangular,rnHexagonal And Octagonal Shapes Whereas Biaxial Chart Is Drawn ForrnSquare Section. This Thesis Also Provides Guidelines To Easily DeveloprnOther Charts For Other Shapes And Material Types That Were NotrnConsidered.rnNumerical Examples Have Been Presented To Illustrate The ApplicationrnOf The Charts For The Design Of Composite Cross-Sections. Results HavernBeen Compared With Those Obtained Using The Procedure Outlined InrnEBCS 4-1995 And Have Shown Close Similarity. The Accuracy OfrnViii Biaxial Charts As Compared With The Approximate Method In EBCS 4-rn1995 Has Also Been Shown With The Help Of A Numeric Example.rnKeywords: Concrete-Filled Tubes, Uniaxial Bending, Biaxial Bending,rnPlastic Capacity, Interaction Chart