Quick Pole Verification

This Nonlinear methodology is the one most often referred to in Codes. It was developed initially to better assess poles with heavy equipment. However, it was found that all structures are better assessed when this Nonlinear analysis method is used. The tests are broken down into structures without guying first, followed by those that include guying. Without guying, this Nonlinearity is essentially the familiar P-Delta effect. For Geometric Nonlinearity with guys attached to the structures, the change in angle and length of any attached guying is also considered as the pole deflects.

The following structure tests are suggested. The loads were carefully chosen to be much less than the buckling capacity of the poles so that geometric effects are measured and not the software's ability to deal with "near-unstable" conditions.

1. Use 40 ft, 50 ft and 60 ft poles; classes 4 and 1. Pole Species to be Red Pine with CSA rating for Modulus of Elasticity (8894 MPa).
2. Apply a 20,000N vertical load at 2 feet from the top of the pole for the 40 ft pole, 15,000N for the 50 ft pole and 10,000N for the 60 ft pole. Also place a 1000 Newton horizontal load to help start the reaction.
3. Perform a P-Delta Nonlinear analysis and note the pole top deflection and the Groundline stresses and moments.
4. Repeat these tests using NESC ratings for Modulus of Elasticity and physical dimensions.
5. On the 40 ft class 4 pole, add one guy at the vertical load attachment height that is at 90 degrees to the horizontal load at a lead of 5.0 meters.
6. Note the guy component forces and the Groundline stresses and moments.
7. No wind or storm loads.
8. No overload factors.

The first set of tests (1-4) are used to validate the P-Delta like scenarios for both CSA and NESC rated poles.

The second set are to validate that the software tool does Guying Nonlinearity, which is required to be able to say that the tool performs a full Geometric Nonlinear Analysis. If the tool does not implement this feature, it will only support loads in its original direction plus generate vertical loads.

Both P-Delta and Guying Nonlinearity combined are required to prove the software tool implements a full Geometric Nonlinear Analysis.