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0

If you mean a cylinder with the diameter $Dcm$ and a square with a side $A=Dcm,$ The square is stronger, solid, or hollow. If they have the same moment of inertia, I, then they are equally strong only for bending moment, but then the square post has a bit less area and a bit weaker for the axial load. let's see what size square has equal I as a cylinder with ...


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Here's my solution in GNU Octave. Everything is in inches. The formula you used (fix-fix support) gives 0.412" deflection for S-40 and 0.437" deflection for S80. clc, clear format long E = 400000 ; D_1 = 1.315; d_1 = 1.049; d_2 = 0.957; w_1 = 0.32/12; w_2 = 0.41/12; L = 10*12; I_1 = pi/64 * (D_1^4 - d_1^4); I_2 = pi/64 * (D_1^4 - d_2^4); fprintf(...


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For schedule 40 pipe: I = \Pi x (1.315^4 - 1.049^4)/64 = 0.0873 in^4 \delta = [0.32(lb/ft) x (10 ft)^4 x (12 in/ft)^3]/[384 x (400000 lb/in^2) x (0.0873 in^4)] = 0.4124" Please check my math.


1

The formula is correct, the answer is likely wrong. Let's look at the two variables that can affect the outcome. The weight and the I. The schedule 80 I is. $$I = π (r_o^4 − r_i^4) / 4 = \pi ( 1.315^4-0.975^4)/4= 1.898"^4$$ $$\delta= \omega*120"^4/384EI $$ The schedule 40 I is. $$I = π (r_o^4 − r_i^4) / 4 = \pi ( 1.315^4-1.049^4)/4=1.397"^4$$ this gives a 1....


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You probably have mixed up the units (i.e. you have 10 ft pipe and inches for the Moment of area) The formulas I've used: $$ d_{max}= \frac{5wL^4}{384EI} $$ $$I = \frac{\pi (d_o^4 − d_i^4)}{ 64}$$ the values I've used are the following: Type Outer Diameter Inner Diameter Weight Schedule 40 1.315” (0.0334m) 1.049” (=0.0266m) .32 lbs/ft (=4.67 N/m) ...


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In flow problems, it's generally a good idea to work backwards in realtion to the flow: Find where each branch is ending and the pressure at this point (height, atmospheric pressure, $p_{out 1}, p_{out 2}$ ). Then, find the relation between pressure loss and flowrate for each branch ($\Delta p_1(Q_1), \Delta p_2(Q_2)$). You know the the pressure at the ...


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Found this reference , a white paper from a firm "Moffatand Nichol," which says Localized areas found between structure and external service yard can be designed as a form of articulation or ‘rocker’ slab, which as the name suggests, allows for normal movements irrespective of on-going settlements. While rocker slabs may be a solution for ...


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The hyperbolic shape of cooling tower is preferred as this shape is stronger against wind pressure. Consequently, the concrete wall thickness can be reduced and optimised. from 1.5m at the base of the viel, the shell thickness rapidly fall to ~30cm. The venturi effect resulting in the usage of this shape is, contrary to popular belief, not improving the ...


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Here is another thought. Have you had your arm on the armrest and someone walked by with a bag or otherwise just carelessly bumped into or smashed your arm? It might be nice to have a little of the bench sticking out to make passersby not cut in so close. I guess spikes like they put on chariot wheels might be more effective, but this design looks nicer.


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What appears to be missed here is the amount of wasted space. Would the bench have enough room for another person if the arm rests were moved to the edge? From looking at that picture there may be enough room but it would need to be a smaller person and possibly a child. There is also the consideration of how many people are expected to sit on it at once. Is ...


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I think you are referring to ‘vertical curves’ for the slope transition of roadway to bridge. Also known as parabolas. The graphic transition can be accomplished with a spline. Bezier is a spline. See Wiki: Spline


4

In the bench that you show, the slats are supported and held in alignment by the end brackets. The armrests are supported by, and in line with, the legs. You could incorporate the end brackets into the leg structure but this would make for a more complicated moulding that either doesn't allow the same mixture of materials or has too many holes drilled in it ...


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Benches are not usually engineered as such. They are being made by furniture designers, (landscape/interior) architects etc. Now generally these professions put a lot of work into making their items novel in some way (Even if that novelty feels stupid to you). Reason for this is that they are being selected that way from catalogs, trade magazines and display ...


26

I am not sure about this particular design. But in public places, the benches are designed to provide temporary comfort but discourage using them as a vagrant or homeless hang out, hence designed subtle discomfort. Also, they have to be easy to scan by security cameras and not have hard-to-see corners easy to hide contraband material or even explosives! ...


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The frame is externally unstable. ED = R - 3 - S = 4 - 3 - 4 = -3 < 0, unstable. R = number of support reaction S = number of internal joint releases (4 moment releases at the hinges)


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The key is what's called "scale separation". For continuum hydrodynamics to work, there has to exist a length scale that is much smaller than the smallest length scale on which any interesting fluid-mechanical phenomena happen, so that it's safe to treat that length scale as differentially small; yet that same length scale must also be much larger ...


1

I don't know about image editing but for the roads and railroad track transition from a straight path to a rurn there is a transition called "Spiral Easement". basically, it gradually eases into the turn and it is a 3-dimensional curve starting from a flat straight path gradually joining the turn with the transversal pitch required to make the ...


1

They are called park model RVs. There are several million of them in the US. The axles and hitch can be supplied by the tow company if you don't want to move it yourself. An even closer fit would be a FEMA trailer, which are built to minimum standard specs.


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Fill it with water. It looks like it's solid on both sides and at both ends. Fill the water at the same time as the concrete -- you want the water level to be below the concrete level to avoid leakage and/or washout on the cement pour side. On the other sides a slow leak doesn't matter. After the concrete is poured, a slow leak on the concrete side won't ...


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The air entrained in the concrete causes discontinuous voids, which will not cause water to penetrate the concrete. Water will permeate through the bleeding pores which are continuous cavities. The entrained air bubbles are small and will only allow space for the freezing water to expand.


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Where concrete is exposed to water, the water is going to permeate concrete no matter what you do (for the most part). The voids introduced by air entrainment allow the water some place to expand into when it does eventually freeze, thereby reducing the pressure on the concrete to crack. Edit 2021/02/17 to add some supplementary information: ACI 201-16, &...


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By definition, bearing stress is the resulting stress between two rigid bodies in contact. It is relevant to concrete only because of its brittle nature, and prone to crack (weak in shear). On the other hand, reinforcing steel does not have such weakness, while it shares/feels the stress, the result rarely be meaningful and detrimental. So for all practical ...


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Where I live, the pressure is created due to reservoirs / lakes being up on mountains close to glaciers... One thing that is done is the use of pressure relief valves that control the pressure and some are designed to drive samll turbines to produce electricity - there are papers on this topic.


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