Rebar, Grade 8.8 Bolts and s355 steel

[bojoka4052]

What are the differences between these 3:

We can use either Rebar or Grade 8.8 Bolts? - and these can be of steel type s355 for example?

 

[desertfox]

Hi

Can you be more specific in terms of what you intend to use the materials for.
I doubt with the question you have posted you will get meaningful answers.

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

 

[JLNJ]

Google the chemical and physical compositions of the various materials and you will see the difference. In many ways your materials are apples and oranges.

Generally, one spec cannot be substituted for another, but there is some overlap between steel materials and very occasionally material is dual-certified.

 

[centondollar]

The things you mentioned are not connected in any way, and are ingeneral not to be used interchangeably; i.e., you should not replace bolt material with S355 structural steel, or replace bolt material with rebar, or replace rebar with bolt material, and so on.

Rebar can be hot rolled or cold formed, ribbed (typical) or smooth (rare), with varying strengths (yield strengths 500MPa and 600MPa are common in Europe), varying ductility (typically >2.5%, >5%, >7.5% minimal ultimate strain according to design standard EC2), varying weldability, varying fatigue resistance (usually low), varying ductility and varying resistance to corrosion.

Structural bolts for steel building frames are typically grade 8.8 or 10.9 in Europe; the code does not directly tell anything about the strength. Grade 8.8, for example, has ultimate strength 810 MPa and yield strength 640 MPa.

S355 is a steel grade, which tells you that the yield strength is 355 MPa. There are a lot of different steels with such a yield strength but otherwise varying properties for e.g., hardness, ultimate strain, resistance against delamination and so on. Plate thickness, while not a direct material characteristic, also becomes governing for some types of design: a very thick plate (>40mm in EC3) is more prone to certain types of failure than a thin plate, for example.

You should have learned all of this at University. If you did not, I suggest you brush up on the subjects before doing anything design-related using the aforementioned types of items and materials. This is basic stuff in structural engineering.