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That describes the distance from the arbitrary origin to the upper section's x-centroid. The upper section is a rectangle with a 120 mm base. Therefore, we know the centroid is at the center of the base (60 mm from either the left or right face of that section. However, for some weird reason, the question defines the origin on the left face of ...


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The principle of virtual work is an energy method of structural analysis. While there is technically a principle of real work its utility is low because it's limited to determining displacement at the point of a single concentrated real load in the direction of that applied load. The principle of virtual work gives us far more power and flexibility in ...


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When making structural analysis with FEM, do we normally use plate or shell elements to represent slabs? You really need to specify what software you are using. The names "plates" and "shells" may be used for very different finite element formulations. Another name sometimes used is "membrane element". Since you have specified the "structural engineering" ...


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So if the vessel is rectangular , I assume a flat heads, essentially no different than a side. So the size of sides and heads would determine the necessary thickness. In traditional cylindrical pressure vessels the stress is reduced by about half in domed heads , so they may be thinner .


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At balance you will have the situation: $ f\times cos(a)\times r = F \times R $ To get the bridge to lift you will need f greater than the balance value. Note that with the bridge pivot as drawn you can't get the bridge fully up and if you lift it fully up the actuator can't pull it down as it is past "top dead-centre". Top dead-centre will occur when the ...


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there are several reasons. Fire hazard: A space as large as these big box floor areas have to be divided into smaller fire skirts on the ceiling to contain the spread of a potential fire. If you look up to the ceiling you will see it is being partitioned by either corrugated sheets or some other noncombustible material hanging from the ceiling into a square ...


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I would call this “site hoarding” (google images preview below - is this what you’re thinking of?)


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Checking with elastic capacity or plastic capacity depends on the limit state you are designing in: For design check in the Serviceability Limit State (SLS) you are interested in small deflections. So you use the elastic resistance of the section. For design check in the Ultimate Limit State (ULS) you are interested in the final resistance capacity of the ...


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If your sketch is up to scale you need not worry about buckling under compression. This column will fail under the bending moment long before it reaches the critical buckling load. This is the critical load for an axially loaded column. $$ P_{cr} = \pi^2\,E\,I\,/\,L^2 $$ And this is the Secant formula for an eccentrically loaded column. Where e is the ...


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A structural engineer should never conduct their own soil testing unless being supervised by a competent person. This is not your area of expertise, let the geotechnical engineer do their job. Generally the geotechnical engineer should outline any risks specific to the site that way other engineers can design for them. An example of this would be ...


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A close approximation is to equate the potential energy of the weight of the worker falling by the amount of the slack, h by the strain energy of the eyeball beam. Assuming he drops clean with no entanglement with the rope into the eyeball and then by ignoring the weight of the eyeball, it bends the eyeball down in a cantilever deflection. $$ mgh= \frac{3\...


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That equation does not distinguish between large and small beams. It is as valid in this case as any other. But this will only be a problem if $h \gg 0$. Remember that $h$ isn't the height of the beam, but the "drop height". How much slack would be expected on the lanyard? If it's small, it won't be a problem. At an extreme, if you can assume no slack on ...


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If you're reading sources referencing terminology other than ASD or LRFD, I'd stop reading them because they're outdated. They're both limit state designs. See the article below. ASD is considered strength design because it's a design approach centered around reducing the strength capacity. https://www.bgstructuralengineering.com/BGDesign/BGDesign05.htm


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They're the same thing. See the link below for an article by the Portland Cement Association. Just different vocab from different regions of the country. Another common example of this in structural engineering is mat slab versus raft slab. They're synonyms. https://www.cement.org/learn/concrete-technology/concrete-construction/contraction-control-joints-...


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The general rule of thumb is never to introduce a degree of complexity you don't need. Use the expected behaviour of the structure to determine the element type. A two-way slab is usually best modelled as 2D elements (plate elements) and an orthotropic bridge deck is often best modelled using 1D elements (beam elements) because it consists of elements which ...


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Base shear is the result of any type of analysis, including pseudo lateral load and seismic analysis.


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Increasing the R factor decreases the load that the building has to resist during an earthquake. Any easy example of this is a wood building. The cheapest choice for wood shear wall sheathing would be gyp board, with an R of 2. If you're in a high seismic area, the forces on that are going to be huge. Using structurally rated shear panels, like OSB, allow ...


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