Alternative Support Systems for Cantilever - National Transportation ...

Figure 5-7. Torsional moment and rotation plot for torsion test
5.1.3 Summary of Torsion Test
Rear of Shaft
The alternative support structure proved effective at transferring torsional load during the
initial testing. It was determined that the modified anchor breakout equations accurately
predicted the behavior and strength of the failure within 0.16% error. See Table 4-1 and
Equations 3-5, 3-6, and 3-7 for the predicted strength that the experimental results verified and
the equations that derived the predicted strength. The test specimen had a cone shaped blowout
failure within the foundation at the approximate location of the torsional plates. It was also
determined that the alternative tested had approximately twice the strength of the calculated
strength of an equivalent anchor bolt system (See Appendix B). For more details on the
calculated strength of an equivalent anchor bolt system compared to the test apparatus’ strength,
see the test apparatus calculations in Appendix B.
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Face of Shaft
Outer Base Plate