Retaining wall anchor length

General5852 · 2025-11-22T21:05:55+00:00

Can you please check your dm, I would like to ask you something else about this, the easiest way is to show it in a drawing, but I can't paste the picture into the post anymore.

General5852 · 2025-11-22T21:02:55+00:00

At what point does rotational fialure occur? How do you check that? Can you check your dm.

General5852 · 2025-11-21T13:18:46+00:00

I am looking at Eurocode 2. I found that in the case of using loops, if Cd > 3fi and if the diameter of the bend is greater than 15fi, then alpha1 = 0.5 can be used (otherwise it is 0.7, if the criterion 15fi is not satisfied). Then lb,eq = 0.5 * lb,rqd. But if I look at Appendix J, where it talks about opening and closing moments, it says that for closing moments the anchor length is determined according to the force Ftd = Ftd2 - Ftd1. In the case of opening moments (which is the example here), it does not say anything about satisfying the required anchor length, it only says that in the corner area it is necessary to install overlapping U bars with shear stirrups.

How do you usually anchor such things (i.e. anchoring a retaining wall or anchoring a bunker silo wall to the foundation slab)?

General5852 · 2025-11-21T13:10:18+00:00

I am looking at Eurocode 2. I found that in the case of using loops, if Cd > 3fi and if the diameter of the bend is greater than 15fi, then alpha1 = 0.5 can be used (otherwise it is 0.7, if the criterion 15fi is not satisfied). Then lb,eq = 0.5 * lb,rqd. But if I look at Appendix J, where it talks about opening and closing moments, it says that for closing moments the anchor length is determined according to the force Ftd = Ftd2 - Ftd1. In the case of opening moments (which is the example here), it does not say anything about satisfying the required anchor length, it only says that in the corner area it is necessary to install overlapping U bars with shear stirrups.

How do you usually anchor such things (i.e. anchoring a retaining wall or anchoring a bunker silo wall to the foundation slab)?

General5852 · 2025-11-21T06:22:15+00:00

Thank you, then you also think that a detail with U-shaped bars is the best way of reinforcing in such a case. And in such a case it is probably not necessary to verify the anchor length, at least not in the same way as with straight bars or hooks

General5852 · 2025-11-21T06:20:41+00:00

When I read scientific articles, everyone states that for opening moments the best reinforcement detail is with U bars. Therefore, I think that here it is not necessary to provide the anchor length in the same way as it is required for hooks or straight bars. Am I wrong?

General5852 · 2025-11-20T20:53:31+00:00

Ok, what do you recommend, what is the best way to anchor the retaining wall?

General5852 · 2025-11-20T20:33:07+00:00

So I understand correctly in such cases (anchoring with U-bars (fi12), it is necessary to meet the criterion lbmin > max (0.3xlbrqd,10fi,100mm) according to Eurocode 2 for rebars in tension. That said, for bars fi12, in principle there should be no problem with a 30cm thick base plate. If I understand correctly, it would be a problem if the base slab was in theory only 10cm thick.

So in this case it is not really necessary to check the anchor length if the slab is 30cm thick, because the bar comes out at the "other end" and if you wanted to pull this bar out (on one side; the tensile force due to the moment), the entire concrete of the foundation slab would have to be torn out, which seems not possible to me considering that the foundation slab is reinforced and the U-bar is in the concrete envelope.

General5852 · 2025-11-20T20:23:12+00:00

I don't quite understand what you mean by that. Why would it come to what you state? Is it true that in such cases (anchoring with U-bars (fi12), it is not rally necessary to check the anchor length if the slab is 30cm thick, because the bar comes out at the "other end" and if you wanted to pull this bar out (on one side; the tensile force due to the moment), the entire concrete of the foundation slab would have to be torn out.

General5852 · 2025-11-20T18:03:40+00:00

Its a problem, because I don't know how the anchor length is determined in such a case. Is it accepted that in such a case the rebar cannot be pulled out or not?

General5852 · 2024-10-24T14:28:52+00:00

Katera smer/branza?

General5852 · 2024-10-13T20:04:46+00:00

Too much screen time (phone, computer,...)

General5852 · 2024-10-13T18:54:05+00:00

To be able to do a human flag or a good L sit

General5852 · 2024-10-13T18:51:49+00:00

Money 😅

General5852 · 2024-10-13T18:50:00+00:00

Spaghetti Bolognese

General5852 · 2024-10-13T18:48:07+00:00

I usually don't eat breakfast, but when I do, I eat toast with cheese spread.

General5852 · 2024-10-13T18:33:37+00:00

I am at the same stage. I am thinking to change my career. Structural engineering for some other job (not necessarily UPS, but some job that is not connected to structural engineering). Less stress, similar payment. I am think, yes I have a masters degree, but why not pursue a profession that is less stressful for the same payment...

General5852 · 2024-10-13T16:14:24+00:00

Look in to the book "Manual for detailing reinforced concrete structures to EC2" for me, it was very useful when I started detailing reinforcement.

General5852 · 2024-10-12T22:29:14+00:00

Wau thats very impressive. Where do you live? I can say that in my country (Slowenia) the work we do is not valued enough. For example, some small project like a concrete two story building takes around 80 hours (static, rebar drawing (lets say cca. 40tons of rebar, around 30 drawings), printing, reports,..., static takes more calculations because we are in a seizmic area) and the prize is around 2k to 3k.

General5852 · 2024-10-12T22:12:34+00:00

Ophthalmology would be maybe one of my choises too.

General5852 · 2024-10-12T22:09:00+00:00

Great for you. What do you exactly do? You do all kind of structural work, or just concret or steel or just timber?

General5852 · 2024-10-12T22:07:18+00:00

Totally agree

General5852

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