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Why would a bearing plate that further concentrates load onto small surface be used?

Because bridges and other structures are not static objects. They must be allowed to flex under varying loads and also accommodate changes in length from thermal expansion. The hinge pin allows ...
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20 votes

Aluminum weight saving

I believe it has less to do with strength and more to do with stiffness. A rod of aluminum of the same length and weight as a a steel rod will be just as strong (force required to break) but have ...
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19 votes

How thick is it reasonable for the walls of a steel gas pipeline to be?

It seems realistic to me. This is an undersea pipeline at depths of over 2 km. The pressure would be considerable at those depths (on the order of 20 MPa or 200 atmospheres). The pipe would need to be ...
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19 votes

Is it structurally sound to cut an I beam to a T on one end?

While not an ideal situation, it is common enough that this type of cut/reduction of the beam as it comes to its support actually has a name. This is more often referred to as a coped or dapped steel ...
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18 votes

Do "non-iron steels" exist?

Steel is defined as an alloy of iron and carbon; there is no such thing as a non-ferrous steel. If you alloy some other metal with carbon, it becomes something other than steel. Looking for a steel ...
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17 votes

Why do we use multiple reinforcing bars instead of one bar with a big diameter in reinforced concrete?

There are a few reasons. I'm firstly going to assume you're talking about replacing a bunch of small rebars by a single reasonably-sized one: i.e. instead of $15\phi8$ (7.54 cm2), using $1\phi32$ (8....
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16 votes
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Can we change steel properties by application of magnetic field while quenching?

This will at least depend on the: Rate of Cooling Magnetic field strength Exact composition The magnetic field will alter the microstructure as you can read in, for example, Yudong Zhang, Nathalie ...
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16 votes

Is it structurally sound to cut an I beam to a T on one end?

This is a textbook example of what not to do. We don't get into stress concentration at the cut off of the corner of the beam, or the fact that the two very different stiffnesses of the beams are a ...
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15 votes

How does width and thickness affect the stiffness of steel plate?

The stiffness of a rectangular cross section, be it steel, concrete, wood, or any other material, is related almost entirely to it's modulus of elasticity, $E$, and it's moment of inertia about the ...
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15 votes
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Is stainless steel plating possible?

Keeping things simple, steel is an alloy of iron and carbon, whereas stainless steel is essentially an alloy of iron, carbon and chromium or iron, carbon chromium and nickel. All forms of steel, ...
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13 votes
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At what temperature do I risk altering the structure of steel?

In general, you want to stay below the recrystallization temperature. Steel is composed of grains, and different types of steel have different grain sizes. The size of these grains affects the steels ...
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13 votes

How thick is it reasonable for the walls of a steel gas pipeline to be?

Is such wall thickness realistic for an industrial gas pipeline? Looking through ASME B36.10M-2004, Welded and Seamless Wrought Pipe, there are plenty of pipes that have thicknesses in that range. ...
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13 votes
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Why do manufacturers still make aluminum kitchen utensils?

Yes, steel (even some stainless) may be cheaper than aluminum, but the material cost of an item is seldom the majority of the total cost, especially a small item such as a potato peeler. Making ...
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12 votes
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What does the steel grade "11SMn30" mean?

Based on it being an EN steel grade: The first number is 100x the carbon content percentage (so 0.11%), the letters are added elements (sulphur and maganese), and the last number is the sulfur ...
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12 votes
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How can the alloying materials of recycled steels be separated?

That is correct, there are a number of unwanted, or tramp, metals (Cu, Sn, Sb, As) that enter the recycling stream from, for example, car bodies that are ground into scrap without removing all the ...
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11 votes
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How does the strength of a square tube depend on the side size?

Flexural capacity is based on the stress at the extreme fiber (the point farthest vertically from the neutral axis). $$\sigma = \frac{My}{I}$$ Or, rearranging $$M = \sigma \frac{I}{y} = \sigma S$$ ...
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11 votes
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What happens from B to C in this stress strain diagram of mild steel?

One point of note is that the yield region is not as cleanly defined as BCD is in the image (although most books have it that way). In reality the yield region looks like The following image is one ...
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10 votes
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At what point does an I-beam becomes a H-beam?

BS5950-1:2000 Clause 1.3.23 defines an H-section as having "an overall depth not greater than 1.2 times its overall width", and Clause 1.3.25 defines an I section as having "an overall depth greater ...
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10 votes

Why do we use multiple reinforcing bars instead of one bar with a big diameter in reinforced concrete?

The main purpose of rebar is to improve the tensile strength of concrete and in practice most of these loads come from bending rather than pure tension. When a beam in subject to bending forces the ...
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10 votes

Why would a bearing plate that further concentrates load onto small surface be used?

The reason is pretty simple. Steel is significantly stronger than concrete. Nowadays we have high-performance concretes with $f_c > 100~\text{MPa}$ (and ultra-high-performance, which is ...
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9 votes

Steel selection for building a trailer

Here's the formula(s) we use Beam Bending (available on Wikipedia) $$EI\frac{d^4\,\delta y}{d\,x^4}=q(x)$$ $$I=\int (y-\bar y)^2 dA$$ $$\bar y= \frac1{A}\int y \;dA$$ $$\sigma_{max} = y_{max}E\frac{...
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9 votes

What do you call the steel property that reduces the likelihood of shattering?

There are three (or four) possible terms for what you are asking: resilience, ductility or toughness (a steel that is resilient, ductile and/or tough) A material's resilience describes its ability to ...
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9 votes

Steel vs Bamboo strength types/ weight and in various directions & orientations? Specific, Tensile, Compressive, Shear, Lateral etc?

Stating categorically that bamboo is stronger than steel is a bit like stating that automobiles are faster than planes. On its face, it is a bit shocking, and seems wrong. But a rocket-powered ...
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9 votes

Aluminum weight saving

TL;DR: Materials perform differently under different loading conditions. Some applications are more suited for steel others for aluminium I will try to give another more general perspective/approach, ...
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8 votes
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What bolts should I specify with Weathering Steel?

For structural applications (in the US), the most common bolt for weathering steel is ASTM A 325 Type 3. Type 1 is a plain steel bolt that can be galvanized, but in this situation the zinc in the ...
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8 votes
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Why are hyperboloid towers not popular anymore?

Meet Vladimir Shukhov, a Russian architect who first developed hyperboloid structures. He was born in 1853, died in 1939, and created over 200 hyperboloid structures in the intervening years. He was ...
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  • 2,485
8 votes

Are threads machined from high tensile steel more susceptible to damage?

First, I want to say that I'm suspect of that material actually being ASTM A311 (though I don't have a copy of that standard available to verify.) Looking on Matweb, this material is the closest I ...
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8 votes

Biaxial flexure of steel I-beams

The simple answer is: "yes, you can use the given equations with Pr=0." There are three reasons for my answer: The code section (AISC 360, Chapter H) doesn't specifically state that Pr cannot be ...
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8 votes
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How to strengthen an I beam

If your beam design is governed by yielding in bending (not lateral-torsional buckling/plate buckling, etc) then you need to increase the second moment of area (I) to increase the bending capacity. ...
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