Hello, everyone.
This is Enta.
What exactly is an initial load?
Since I was asked about this, I thought I'd write about it.
The book includes"The tensile force applied to the tendon when tightening and securing the anchor"
It says...
Well, I guess that makes sense, but that doesn't really explain it, does it?
Generally speaking, the illustration looks something like this.
However, in actual field conditions, the jack is set up on the prestressed steel strand as shown below.
I know I'm exaggerating a bit, but since the jack is set up and the tire isn't inflated yet, it's just hanging there all limp.
The test cannot begin in this state. The dial gauge cannot be installed either.
For that reason, we apply an initial load to tighten the jacks and PC strands.
That's the state shown in the picture above.
Once it gets to this point, it barely moves even if you kick it with your foot!
Even though it’s called an initial load, it’s still several metric tons, so it doesn’t budge an inch.
An initial tension of approximately 0.1 to 0.2 times the maximum design load is sufficient.
It's just a matter of getting the jack and the PC wire all set up, lol.
However, if the bearing capacity of the natural ground is low, a force of approximately 0.3 times the planned maximum load may be required.
I believe that will be up to the judgment of the ground anchor installer.
See you later.
I always find your articles very helpful.
I believe this article is about initial load rather than initial tensile force—is that correct?
Initial Tension Pi: This is the maximum tensile force applied to the tendon when the anchor head is tensioned and set; the tensile force acting on the tendon immediately after setting is referred to as the setting tension. The initial tension is determined by taking into account the reduction in tensile force resulting from factors such as the setting depth of the anchor.
Initial Load: A term used in basic survey tests, etc. (as described above)
Please review the following sections of the Ground Anchor Design and Construction Guidelines and the accompanying commentary.
6.7 Tension During Fixation
7.11: Tension Stabilizes
Appendix 6
6-8 Initial Tension and Anchorage Tension of Anchors Used for Slope Stabilization
6-9 Initial Tension and Tension at Anchorage of Retaining Wall and Slope Anchors
6-11 Factors Contributing to a Decrease in Tension During Anchor Installation and Their Effects
Thank you in advance.
Thank you.
I fixed it lol
We look forward to your continued support.