analysis and design og different shapes of high strength concrete columns

in fact the most suitable method for finding the load bearing capacity of a member under the axial load or axial load and bending is make use of the interaction diagrams. to analysis and design the hollow circular, square and rectangular high strength concrete (hsc) column shapes, a linear strain variation was assumed in the cross-section height of the members and then the static equilibrium equations are written by considering the properties and relationships governed in (hsc).based on this, for different variables such as, concrete compressive strength, reinforcement stress, concrete cover, ratio of thickness to the section dimensions and the bars arrangement, a computer program was developed by the matlab software and the total number of 441 interaction diagramed were drawn for (hsc) columns. the use of such diagrams is a safe and easy tool for analysis and of hollow hsc columns of different shapes.