One option could be to divide whole column in segments, estimate the average moment of inertia of each segment based upon given dimensions and integrate along the length for the given loading condition to find out the deflection at selected location along the length. You may have to go back to your Mechanics of Materials Textbook and look at one of the methods given to integrate along the segmented column, or Another Option Google out for the 4th Edition of the Standard Specifications for Structural Supports for Highway Signs, Luminaries, and Traffic Appendix B3 for tapered poles. You may have to search for a bit in the web, but if you do not find a specific formula, then use your good friend textbook of strength of materials and set up something n Excel or so.
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Pedro Munoz Ph.D., P.E., M.ASCE
Principal
PRM Engineering, LLC
Methuen MA
(978)7388001
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Original Message:
Sent: 12-03-2018 11:21
From: Qusay Al-Kaseasbeh
Subject: HOW TO CALCULATE THE EQUIVALENT MOMENT OF INERTIA FOR A GRADED-THICKNESS CIRCULAR COLUMN?
If I have a thin-walled steel tubular circular column with graded-thickness along its longitudinal axis. How can I get the equivalent moment of inertia for the whole column?
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Qusay Al-Kaseasbeh S.E., S.M.ASCE
Grand Forks ND
(701)885-2412
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