Circular Column Interaction Diagram Spreadsheet

Circular Column Design

Circular concrete columns are commonly used in concrete frame buildings and structures. Circular columns are typically used either for aesthetic reasons or where the column can be subjected to bending moments in any direction. This is common in wind loaded structures for example. Concrete is both durable and fire resistant which makes it useful in many different types of buildings and structures.

Reinforced concrete is also well suited for use in columns due to its strength in resisting axial compressive forces. When concrete columns are subjected to tensile stresses from bending moments, the concrete is reinforced with steel. When these tensile stresses can occur in any direction a circular column is required. A minimum amount of steel is included in all concrete columns in order to minimise and control cracking. The quantity of reinforcing steel required is determined by the size of the bending moments to be resisted.

This spreadsheet is used to design circular concrete columns only. For rectangular columns, our Rectangular Column Design or Biaxial Column Design Spreadsheets can be used. Both these spreadsheets are included in the Concrete Column Design Bundle which also includes the circular column design spreadsheet.

Circular Column Design - Inputs

The first step in circular column design is for the designer to input the axial and bending moment forces acting on the column. The circular column design spreadsheet allows the designer to input up to 6 load cases from a separate structural analysis.

It is not possible for the designer to determine the critical load without a detailed analysis first. This is because the maximum axial forces which the column can accommodate depends on the maximum bending moments and vice versa. For this reason the CivilWeb Circular Concrete Column Interaction Diagram Excel Spreadsheet allows the designer to input up to 6 different load cases which are analysed to determine the critical load case.

Next the designer must input a proposed size for the circular column. The circular column design spreadsheet then completes the analysis calculations to determine whether the proposed column size is valid or not. These calculations are completed in accordance with BS EN 1992. The designer can then adjust the column size until it is optimised to the precise loadings present in this column.

After the column dimensions have been finalised the CivilWeb Circular Concrete Column Interaction Diagram Excel Spreadsheet can then be used to design the reinforcement. The reinforcement in circular columns is installed all around the perimeter of the column. This means that the column is able to resist bending moments acting in any direction, for example wind loads which can act in any direction.

The circular column design spreadsheet also produces a unique column interaction diagram which shows the designer the critical load case combination of axial load and bending moments. The critical load case may not be the largest axial force or the maximum bending moment. This is because the interaction between maximum axial load and maximum bending moment is not a simple linear relationship.

The column interaction diagram shows the designer at a glance where the column design can be optimised. The chart shows the designer the limits for each standard bar size at the chosen spacing. If the designer has a particular maximum or minimum bar size in mind it is simple for them to tweak the column size and the reinforcement spacing to suit.

CivilWeb Circular Column Interaction Diagram Spreadsheet

The CivilWeb Circular Column Interaction Diagram Spreadsheet is an easy to use spreadsheet for the design of circular columns in accordance with BS EN 1992. The spreadsheet completes all the calculations instantly allowing the designer to complete a fully optimised design in minutes. Unique reinforcement interaction charts also show the designer the optimum design.

Buy the CivilWeb Circular Column Interaction Diagram Spreadsheet now for only £20.