Wasabi
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You messed up your integration from $EI\dfrac{dy}{dx}$ to $EIy$. It should be $$EIy = \dfrac{75x^3}{6} - \dfrac{15x^4}{24} + c_1x + c_2$$ but your denominator for the first term is $3$, not $6$. (In ...

Yes. The first derivative of the deflection is equal to the tangent of the deflection, which for small deflections can be approximated as equal to the angle of rotation of the beam at each point. ...

Your assumptions are incorrect. The breaking point will almost always be at the fixed point. Here are the internal forces in your structure with loading at two different positions: Axial force is ...

The use of the smaller diameter is theoretically correct. What is a splice? It is when tension force in a rebar is transferred to the concrete via adhesion and then to another rebar. Since concrete ...

The reality is a bit more complicated, and depends greatly on the materials being used. Let's take the following structure as our example, where the middle support may or may not be hinged (creating ...

Reading your question, my understanding is that you trust your engineer to have done at least a reasonable job designing the structure. You aren't worried the structure might collapse, that the ...

The equation to find the center of gravity of an object which can be subdivided into smaller parts is the following: $$\text{CG} = \dfrac{\sum \overline{y}_iA_i\rho_i}{\sum A_i\rho_i}$$ where $\... View answer 4 votes You can build this wall as you would any other. Given its size, the fact that it's a ring becomes irrelevant, which means that for all intents and purposes, it can be designed and constructed with the ... View answer Accepted answer 4 votes To quote Wikipedia: The elastic section modulus is defined as$S = \dfrac{I}{y}$, where$I$is the second moment of area (or moment of inertia) and$y$is the distance from the neutral axis to any ... View answer Accepted answer 4 votes I wouldn't be surprised if these tributary angles are merely a rule-of-thumb obtained over time. (Correct me if I'm wrong!). While it makes obvious sense that, in a slab with neighboring fixed and ... View answer 4 votes For a planar surface, the centroid is defined by the equation $$\overline{y} =\dfrac{\int y\ \text{d}A}{\int\ \text{d}A} = \dfrac{\int y\ \text{d}A}{A}$$ where$yis the distance of each point from ... View answer 4 votes What you need is the modulus of subgrade reaction (MSR) of the soil. This is a measure of soil deflection under a given pressure, so the unit is in (for example) kPa/m, or equivalently, as I'm more ... View answer Accepted answer 4 votes As always, the first thing you need to do is calculate your properties. \begin{align} A_A &= 150\cdot10 + 6\cdot(200-10) = 2640\text{ mm}^2 \\ \overline{y}_A &= \dfrac{150\cdot10\cdot195 + 6\... View answer Accepted answer 4 votes The nomenclature adopted by the authors is unusual, yes. Usually that loadQ$would be called a transverse load, as you've mentioned. That being said, there is nothing that distinguishes a lateral ... View answer 4 votes Double-I beams cannot be spliced like single-I beams for the reasons you mentioned. Indeed, they must be spliced like box beams, which suffer from the same problems (lack of access to internal face). ... View answer 3 votes You seem to be mixing up a few concepts. As others have mentioned, bending moment is independent of a structure's cross-sectional dimensions. After all, bending moment is simply the sum of$F_i\ell_i$,... View answer 3 votes Not only can this be done, but it also is done for concrete structures all the time. The shear reinforcement in concrete beams is calculated using Mörsch's truss analogy model: Source The concrete ... View answer 3 votes An extended discussion on internal vs. external forces We usually like to describe hinges as "places where the moment is always zero." But, wait a minute, the moment is always zero anywhere ... View answer Accepted answer 3 votes When you've done an exercise and got the wrong answer, it's always useful to check to see if your result ever passed the "smell test". That is, does your result make much sense. Now, we can see a few ... View answer Accepted answer 3 votes The water table in some locations may vary during the day or over time. For this reason, the borehole drilling process includes waiting periods to see if there are any changes to the water table. The ... View answer 3 votes The Euler-Bernoulli beam equation is as follows: $$q = \dfrac{\partial^2}{\partial x^2}\left(EI\dfrac{\partial^2 \delta}{\partial x^2}\right)$$ where$q$is the distributed load along the beam,$\...

In my professional experience, I've found few opportunities to perform literal "by hand" verification. Unless you're dealing with simple structures (or structures which can be simplified as such), it ...

Real structures do suffer from buckling. Yes, real structures are never perfect. Columns aren't perfectly vertical, cross-sections aren't perfectly consistent throughout the span, the material isn't ...

You came so close to the answer, you ran right past it! As you've said, the stiffness coefficient is defined as force over distance: how much force you need to apply to deflect an object (a beam or a ...

The short answer is you can't. The slightly longer answer is you can, but the solution is specific to the adopted cross-section. The much longer answer will now demonstrate why this is the case by ...

As @mg4w already mentioned in a comment, this is a statically indeterminate structure. This means that the structure can't be trivially solved as you have tried (unless you use a simplifying ...

Your shear diagram is correct. Bending moment is equal to the integral of shear. Therefore, the point of maximum bending moment is the point of zero shear. I can see you calculated that point as 4.38,...

Your result is correct: member 4 is what's known as a zero-force member. This result is inescapable given it's definition as a rod which can only take in axial loads. Since it's on a diagonal, any ...