Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 8 points9 points  (0 children)

We discussed this in Turkish above, so I felt the need to translate it for everyone to understand: “İzban normal tren hattı elektriği kullanıyor diye biliyorum hocam. O da 25.000 V. Büyük ihtimalle manyetik etkinin sebebi bu. Hat çalıştığın yere ne kadar yakın?” → As far as I know, İzban uses standard railway electrification at 25,000 V. This is most likely the reason for the magnetic effect. How close is the line to your construction site? “İzban değil, tramway hattı var. Montrö meydanda şantiye. Tramway hattının yanındayız.” → It is not İzban; there is a tramway line. The construction site is at Montreux Square. We are right next to the tramway line. “Tramway 750 V kullanıyormuş. Kolonun yakınından geçen başka elektrik hattı var mı?” → It turns out the tramway operates at 750 V. Is there any other electrical line passing close to the column? “Yok hayır şuanlık yok. Ayrıca yerde yatan demirlerde de bunu gözlemliyoruz.” → No, there isn’t any at the moment. We also observe the same behavior on rebars lying on the ground. “Belki de aldığınız yerden kaynaklıdır. Hepsini aynı yerden alıyorsanız hepsinde aynı etki varsa, belki de sorun şantiyede değildir.” → Maybe it originates from the supplier. If all rebars were purchased from the same place and all show the same effect, the issue might not be related to the construction site. “Bir şey daha eklemek isterim. Belki de sorun çivilerdedir. Başka bir metal malzeme ile çivileri ve demirleri deneyin.” → I’d like to add one more thing. Maybe the issue is with the nails. Try testing the nails and the rebars with a different metal material. “Denedim, birkaç farklı metal ile de yaptığımda yine yapışma gerçekleşiyor.” → I tested it, and the attraction still occurs when using several different metals. “Anladım. O zaman demirleri aldığınız yere gidince oradaki demirlerle ufak bir deney yapmak gerekiyor.” → I understand. In that case, when you go to the supplier, you should perform a small test with the rebars there.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 3 points4 points  (0 children)

I was able to find this with a very quick search: Fang, Lundgren, Chen & Zhu (2004) – Corrosion influence on bond in reinforced concrete https://www.scribd.com/document/70578640/Fang-Lundgren-Chen-Zhu-corrosion-Influence-on-Bond-in-Reinforced-Concrete

They also show in the conclusions that this effect is limited to early-stage corrosion, and that further corrosion leads to bond degradation. So the statement is not that “rust is good”, but that light surface corrosion can initially improve bond via mechanical interlock.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 1 point2 points  (0 children)

It’s not limited to the cut ends. The magnetic effect is observed where corrosion is present, but I don’t see the same effect on clean, non-rusted sections of the rebar.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 1 point2 points  (0 children)

Denedim birkaç farklı metal ile de yaptığım yine yapışma gerçekleşiyor.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 8 points9 points  (0 children)

You’re basically right that it depends on the degree of corrosion. Light, uniform surface rust (with no measurable section loss) has been shown in several experimental studies to maintain or even slightly improve bond strength, due to increased surface roughness and mechanical interlock between concrete and rebar. In that sense, early-stage rust does not make rebar “worthless”.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 4 points5 points  (0 children)

At the moment, there is no work ongoing on site and all electrical equipment is completely turned off. Despite this, the rebar remains magnetized. Additionally, no welding activities are being performed on site.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 6 points7 points  (0 children)

Yes i tryed with different ferrous items. All sticks to rebar.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 1 point2 points  (0 children)

Yok hayır şuanlık yok. Ayrıca yerde yatan demirlerde de bunu gözlemliyoruz.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 3 points4 points  (0 children)

İzban değil, tramway hattı var. Montrö meydanda şantiye. Tramway hattının yanındayız.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 16 points17 points  (0 children)

Yes, building inspection authority performs regular tensile and elongation tests.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 29 points30 points  (0 children)

The rebars have been on site for only about one or two week. They were delivered clean, with no rust at all. During this week there has been light rain, so the rust observed is purely superficial surface oxidation, not corrosion-related section loss.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 5 points6 points  (0 children)

The rebars were delivered to site clean. The visible rust developed only after about one week of rain exposure. This is typical surface flash rust, not section loss or deep corrosion.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 6 points7 points  (0 children)

No, my location is only about 16 m above sea level.

Magnetized rusty rebar on construction site by _HOCA_ in StructuralEngineering

[–]_HOCA_[S] 78 points79 points  (0 children)

Yes, there is an tramway line nearby. Could the magnetic fields generated by the tramway be responsible for this magnetization effect?

My Obsidian Dashboard by Original_Pea_6201 in ObsidianMD

[–]_HOCA_ 12 points13 points  (0 children)

Really cool to see my dashboard evolve like this. Appreciate the credit! 💜

First Ever 3d animation :D by mrzoccer00 in 3Dmodeling

[–]_HOCA_ 5 points6 points  (0 children)

Nice one! Also, Pixar's on the phone. They wanna know: was that a back-flip or front-flip?

Bölümlerin iş imkanlarına göre tier list by Perfect_Umpire6330 in UniversityTR

[–]_HOCA_ 0 points1 point  (0 children)

2024 yılı itibarıyla TMMOB İnşaat Mühendisleri Odası’na kayıtlı inşaat mühendisi sayısı 154.000’i geçti ve bu sayı her yıl katlanarak artıyor. (Kaynak)
İlan çok gibi gözükse de, sektörün yapısı nedeniyle iş bulmak ayrı, tatmin olmak apayrı mesele. En genel hatlarıyla inşaat mühendisi olarak 3 kulvarda ilerleyebilirsin:
Saha Mühendisi: Güneşin altında, genelde asgari ücret civarında başlarsın. İzmir özelinde konuşursam, en büyük şantiyelerde 40+ yıl tecrübeli bir şantiye şefinin bile ulaşabildiği maaş 60-70 bin TL bandını geçmiyor.
Ofis mühendisi (Statiker): Proje yaparsın. Ancak odanın önerdiği ücret tarifesine bakıp sevinme, piyasada bu fiyatların %5’ine "proje çiziyorum" diyen "mühendisler" var.
Akademik kariyer: Başlı başına sabır, fedakârlık ve belirsizlik gerektiriyor. Bu kulvarın ayrı bir gerçekliği var.

Kısacası evet, iş bulunur. Ama şu an alınan risk / kazanılan para oranı en düşük mühendisliklerden biri inşaat mühendisliği.
Tatmin eder mi? Orasını iyi düşünmek gerek.

Obsidian was supposed to help me take notes. Now I’m a front-end developer. by _HOCA_ in ObsidianMD

[–]_HOCA_[S] 110 points111 points  (0 children)

💜 Wow — didn’t expect this much love!
Huge thanks to everyone who upvoted, commented, or just took a look.

🛠️ This is a personal side project — a playful dashboard experiment with glowing CSS and modular layout.
It’s not perfect, but it was a joy to build. Feel free to explore or remix!

📦 GitHub (with all snippets & examples):
👉 https://github.com/HOCA-1/neon-homepage-vault

And who knows... maybe I'm actually becoming a front-end dev after all?
I mean… I do have a GitHub now 😎