# Tag Info

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The direction of Forces isn't necessarily along the connecting element. If that happens depends a lot on the constraints between the different elements. For example see the following image: In the left column is a "welded" structure, while on the right column is a pin jointed structure (a basic truss) if you like. On the top there are the shapes ...

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TL;DR (Serious): The problem is that you don't into account that the bending moment equation changes at different section of the beam. TL;DR: (Tongue in cheek) Don't do this unless you a) really really don't have anything better to do, or b) you are getting paid to do it, c) you really like this sort of problems. :-P (I wasn't getting paid to do it, so I ...

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$EI\dfrac {d^2_y}{dx^2} = M$ Procedures: Write equations for the moment in segment AB and BC as a function of x. Integrate the moment of each segment to get the slope, $EI\dfrac{dy}{dx} = EI\theta_x$ Integrate the slope of each segment to get the deflection, $EIy = EI\Delta_x$ Apply boundary conditions to set up equations for the constants. Solve the ...

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I don't have the book so I don't know what the author means by "Methods Based On Interpolation of Excitation." Practical methods for computer simulations can be based on Duhamel's integral. The idea is to find the impulse response of the system (which is simple for a damped SDOF model of the structure) and then apply an impulse to the structure at ...

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The reason why forces are transmitted in arches is similar to the joint structure in the other question. Additionally there are the internal bending moments that also change the undeformed shape of the element (be it beam or arch). arches build with stone Although not in your original post, I will focus on the forces in stone arches. In order to understand ...

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There's nothing like kicking the dirt. I would advise actively participating in a manhole inspection, at least once so you know what it like. Do an inspection with an experienced person. By doing so you will have first hand experience of what is involved and what can and can't be easily seen or done via such inspections. Doing more such inspections would be ...

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I will add my answer to the others although the results will not be much different. The way I see it the following parameters are the most important: The worst case scenario for the bending of the beam: Instead of the open handle (which is a four point bending), I would go for the close handle (which is three point bending). This is a worst loading ...

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Estimating force You can calculate the section assuming you are as strong as the world record holder for deadlift, which I think is 500kg. Meaning any maneuver, even acrobatic, that can cause a force imparted by the bar on your hands greater than 500kg will cause you to lose grip and let go of the bar. Assuming a distance of 40cm between your hands on the ...

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Nothing fancy. Just mild steel. Assuming you go with at least 1"/25mm diameter for ergonomic purposes, go with a wall thickness of 3/16"/5mm which already should be overkill. At 6ft/2m long and 1"/25mm diameter, I am skeptical if 1/8"/3mm wall thickness will be sufficient. I doubt it would break but it might flex under dynamic load. And ...

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The arch works by being deformed and compressed under the vertical loads. When it deforms it wants to settle down and its geometry changes trying to trace a shorter path. But that shorter path means it strains the material creating compression stress in the material of arch, being it pieces of rock or concrete or masonry or even bags of dirt. That is the ...

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You have to break the ground acceleration, $u_{gt}$ into simple segments like what your book example has done. The k if not given can roughly be estimated as a cantilever beam $k=\frac{3EI}{L^3} \$ or calculating the force applied on top that causes the structure to deflect one unit. There are some worked examples to calculate the stiffness of a complex ...

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The natural frequency of the system is given by $$\omega_n=\sqrt\frac{k}{m}$$ So k and $\omega_n$ are related. There is no contradiction.

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I am writing this as an answer to the comment about the superposition method. I started writing it in my original answer, but it was too long and confusing, so I opted to do another answer. Superposition method. Let's assume you have this problem. In that case you only need the following equation. Essentially what you do is you apply the above equation ...

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Strickly to say, this can only occur for fluid materials or airflow. For which you shouldn't have any problem in understanding how the diverging occurs. Diagrams below show how the force flow in a hollow triangle (left), a rigid body (middle), and the random flow of the fluid force. Note there is no surface pressure/force in the first and second cases.

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"How is the effective E determined in this case?" The masonry Modulus of Elasticity (Em) is commonly calculated as the chord modulus of the linear part of the masonry compression stress-strain curve, which is typically defined to be between 5% and 33% of the ultimate masonry compressive strength (f’m) (ASTM 2003a; Drysdale et al. 1999). ...

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