Minimum Distance between pole base and Guy anchor 2

[KillBill7]

I am wondering if there is a minimum horizontal distance requirement between Pole base (directly buried wood pole) and the guy wire anchor. I have seen few utility standards where they specify minimum 3m between each anchor, which I guess is to ensure the ground around each anchor is not compromised. I am curious if the same distance applies for the pole base to the anchor as well.

 

[MR_E30]

Ah, finally a topic I am familiar with.

Ground anchors (of the helical variety, as sold by Chance and Hubbell Power Systems) definitely receive a mandatory minimum distance between each other. This is a function of the burial depth and angle of friction in the soil which determines the 'cone of influence'. In my designs, these cones do not overlap.

However, I do not specify minimum distances between an embedded utility pole and the ground anchor. As a caveat, when the pole is short enough that the guy anchor will be 'close' to its base (i.e. inside the cone of influence) the loading is usually very minimal, and relatively small pull test values result, and I am not worried or concerned.

If for some reason the loading in the guy wire was substantial (10k tension or greater for example) I would perform a more detailed analysis to determine if I need to avoid any disturbed soil to reach my necessary capacities. Though, in my industry, the pull-test (performed according to my specific criteria) is the final word in anchor capacity.

 

[KillBill7]

Thanks for the reply MR_E30. Would you be concerned about disturbing the soil close to pole as it may compromise the pole foundation?

 

[MR_E30]

OP, it would depend on what the installation method of the ground anchor is. Traditionally in the industry I work in the ground anchor is installed with little compromise to surrounding soil. An attachment is placed on the end of a skid steer and the anchor is twisted into the ground. In this case I would not worry about the pole foundation.

I have had contractors that wanted to scoop out a large chunk of dirt, put an anchor in the hole, and then backfill with dirt, or even fill the hole with concrete. In this instance I could become concerned with the pole foundation, depending on backfill practices and forces in the pole.

 

[KillBill7]

Makes sense. Appreciate your response.

 

[oldestguy]

Consider the pole is sitting on a hinge at ground surface and the pull on the line to it is from afar. The farther the anchor is from the pole, the less the anchorage resistance is required. An anchor very close has to be much better under the same circumstances as to pull of the line from afar. Its a simple statics problem.