VM-WB-MECH-012

VM-WB-MECH-012
Buckling of a Stepped Rod

Overview

Reference:

Young, W. C.Roark's Formulas for Stress and Strain (6th ed., Table 34, Case 2a, p. 672). McGraw-Hill.

Solver(s):

Ansys Mechanical

Analysis Type(s):Buckling Analysis
Element Type(s):Solid

Test Case

A stepped rod is fixed at one end face. It is axially loaded by two forces: a tensile load at the free end and a compressive load on the flat step face at the junction of the two cross sections. To get accurate results, apply sizing control with element size of 6.5 mm.

Find the Load Multiplier for the First Buckling Mode.

Figure 12: Schematic

Schematic

Material PropertiesGeometric PropertiesLoading
E = 2e11 Pa
ν = 0.3
Larger diameter = 0.011982 m
Smaller diameter = 0.010 m
Length of larger diameter = 0.2 m
Length of smaller diameter = 0.1 m
Force at free end = 1000 N
Force at the flat step face = -2000 N
Both forces are in the z direction

Results Comparison

ResultsTargetMechanicalError (%)
Load Multiplier22.522.7371.05