Procedure for the experiment is as follows.

1. Pin a graph paper on the wooden board behind the column.

2. Apply the load at the top of columns increasing gradually. At certain stage of loading the columns shows abnormal deflections and gives the buckling load.

3. Note the buckling load for each of the four columns.

4. Trace the deflected shapes of the columns over the paper. Mark the points of change of curvature of the curves and measure the effective or equivalent length for each case separately.

5. Calculate the theoretical effective lengths and thus buckling loads by the expressions given above and compare them with the observed values.

Observation table

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