Wasabi
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Can a horizontal foundation safeguard against earthquakes?
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Things topple when their center of mass moves past their supports. Think of a square box: if you push it over slightly and let go, it'll fall back onto its original position. But if you push it past ...

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Identifying Compression and Tension as well as Hogging
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Once again, the superposition principle is our friend. It basically means we can look at each load in isolation, find the individual results, and then add them all together to get the final result. ...

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Statically indeterminate fixed-pinned beam problem
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Your bending moment diagram is very wrong. It is continuous even though there are concentrated bending moments (which create discontinuities), and you have $F$ generating positive bending moment when ...

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Simple beam with cantilever ends
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You are correct that symmetry demands that rotation at midspan be zero. However, as you also mentioned, there will obviously be deflection at midspan as well. You therefore cannot simplify the ...

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Can bending moments for a combination of loads on a simple beam, be calculated by adding the individual B.M. of each load?
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YES This is known as the superposition principle. For beams composed of linear-elastic materials where all loads are constant and independent from changes in beam geometry (i.e. not rain or snow ...

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How does stiffness/rigidity affect the bending moment of a beam
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As mentioned by other answers, when dealing with a statically determinate structure, the stiffness of each element is irrelevant when calculating the bending moment, but a key variable when ...

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Why do we use simple bending equation when bending moment is caused due to shear force?
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The equation you're talking about is the following: $$\sigma = \dfrac{My}{I}$$ The reason this equation only considers bending moment even though "moment is caused [by] shear stress", is because, ...

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Transfer of moments in beams with internal hinges
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Imagine if AB didn't exist, so all we have is BD with the pinned support at D and the force at C. In this case, BD is hypostatic and becomes a mechanism, rotating around D. Obviously, we know that ...

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stress curve in the notch effect?
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In these cases, it is always worth thinking about how the stress "flows" through the element. In this case, that's quite simple: The stress near the center of the element is basically unaffected by ...

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Why we don't use fillets while making buildings?
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The issue is simply cost. The loads in structures such as benches (which you describe in comments under the question) are very low and such structures often have huge safety margins. These margins are ...

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Difference in shear stress - one bolt vs two
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As others have mentioned, the load will be distributed between the bolts. How they will be distributed is more complicated, but it is usually assumed to be an equal division between the bolts (in this ...

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Included angle in a semicircle
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It's given by the question. If you pay attention to the original image, you'll see that the internal angle ($180−\alpha−\beta$) has the classic right-angle symbol. Source

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Behavior of materials on application of tension
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Yes. In a perfectly elastoplastic material (where the stress-strain relationship is perfectly linear until the yield point and is then constant and equal to the yield point), the material will ...

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HELP Please! Depth of member
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The depth of a member is merely equal to its total height (or whichever total dimension is parallel to the loading direction).

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Translating the name of a type of beam from Russian to English
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This is also considered a simply-supported beam. If you want to be more descriptive, you can call it a simply-supported beam with overhangs (the cantilevers beyond the main span). Basically, any beam ...

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At What height do we splice vertical bars in Columns and Shear walls?
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In theory, a splice behaves exactly like a single continuous bar, so there should be no effect as to where you actually do the splice. However, in the real world it depends. If you're dealing with a ...

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Statics and Structural Analysis: Determinacy in beams/frames
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Whether a structure is determinate or indeterminate is just a description of how easy or hard it is to solve. For a 2D planar structure such as a beam or frame, there are only three global equations ...

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Angle of rotation in fixed end of beam
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Ok. Yeah. Your question seems to be why a fixed support has zero rotation ($\theta=0$). The answer is simple: that's the definition of a fixed support. Here is a table representing the constraints ...

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Calculating the moments due to reaction forces on a bent beam
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The reason is that both the horizontal and the vertical component of $N_B$ generate a moment around $A$. Since the moment due to a force is equal to the product of the force and the perpendicular ...

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Flexural modulus for a beam fixed at one end
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The fundamental beam equation is $$\dfrac{\text{d}^2}{\text{d}x^2}\left(EI\dfrac{\text{d}^2w}{\text{d}x^2}\right) = q$$ Which basically translates to "the fourth derivative of the deflection ...

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internal forces in truss
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As @AndyT stated, you need to add the horizontal reaction at A. You start by finding the reactions. Your global equilibrium equations are $$\begin{align} \sum F_x &= R_{A,x} + F = 0 \\ \...

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Do beams in a structure transmit to piers?
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Questions 1 + 3: Your first question is unanswerable. Any design is theoretically safe. Just create a massively thick slab with high-strength concrete and massive reinforcement and you can do just ...

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shear stress before and after cut
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As @JMac pointed out in a comment, the cut in the beam causes the following cross-section to occur (exaggerating the size of the cut): Originally, the shear stress can flow from the top to the bottom ...

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How to calculate deflection of a cantilever beam subject to point loading
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Both answers are incorrect. Your answer to (a) would imply that the bending moment is equal to zero at $x=0$ and increases linearly until $x=L$. This is only true if you put $x=0$ at the free end of ...

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Beams in Bending: Bending stress / strain distrution
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Before discussing any such matters, we must define our internal force sign conventions. It is common to define them thusly: So, tension is positive, compression is negative. Shear forces are positive ...

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Staad - structure design
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In structural analysis, one represents a real beam (or column, or any other "unidimensional" element) is represented by one or more bars. A bar is defined as a connection between two nodes. If you ...

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How does a constant load affect the elongation of a steel cable?
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This answer will assume the applied load is not enough to damage your structure (the stresses generated are lower than the elastic yield stress). I am also going to ignore the distinction between ...

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IPE Beam weight
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The density of structural steel is usually adopted as 7850 kg/m3 (or thereabouts). According to this source, the cross-sectional area of an IPE 300 section is 53.8 cm2. The linear mass of ...

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Deflection of beam, according to thickness of top plate and bottom plate
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The deflection of a simply-supported beam under a concentrated load at midspan, regardless of the cross-section, is equal to: $$\delta = \dfrac{PL^3}{48EI}$$ So the only thing that changes in your ...

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Structural Analysis of a Space Frame
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You state in a comment beneath @Jodes' answer that since the structure is welded, that the joint can be considered fixed. The veracity of that claim is somewhat arguable (especially if done "...

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