Questions tagged [structural-engineering]
Questions related to the integrity, design requirements, or analysis of structures.
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roller chain FEM analysis
I am planning to do a FEM analysis of a roller chain. I am quite inexperienced in the field of FEM. Could any of you please tell me what sort of analysis (for example static analysis, dynamic analysis,...
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0answers
14 views
Joint Revolute or Fixed?
a shaft is driven by a motor, it is supported in two places by ball bearings and connected in third place by a motor.
how can I use this example in Ansys WB?
1. variant : two places, where the bearing ...
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0answers
19 views
weight bearing capacity of a reinforced concrete floor slab [on hold]
What is the weight bearing capacity per square yard of a 4" monolithic concrete floor slab poured with 3000 psi concrete in 50' x 50' squares, reinforced with 6" x 6" x 10" steel wire mesh, laid over ...
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33 views
Check the drawn projection of this solid body
I don't have solution to the problem, so can anybody check?
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0answers
55 views
Doubt on whether to show cavity in projection of this solid body or not
This is the solid body of which I am trying to do projection
I have doubt in left portion of LSV, will we show cavity or don't show cavity
Also, if possible, please check the lettering style and ...
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1answer
57 views
How thick does my stainless steel table top need to be?
I need to construct a table that will hold a water tank. The filled tank will weigh up to 1300 pounds. I have the table leg frames worked out to hold 2500 pounds so no worries there. (Here is a link ...
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0answers
19 views
Abaqus Failure for I-Beam Section in Major direction only
For my 4th year dissertation in Civil Engineering I've got to investigate the difference between BS5950, Eurocode 3 and ABAQUS failures. The only thing is, in the BS5950 and Eurocode 3 the failure can ...
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0answers
21 views
Beam Defelction Using Macaulay Theorem
I have a simply supported beam and am trying to work out the deflection using Macaulay's Theory, is it possible to verify my results, I feel they are far out, and can not see where the error lies. ...
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1answer
44 views
Sizing crumple zone for multi-vehicle collisions
I need to size bumper beams for the crumple zone of a very lightweight vehicle. Together with the driver, the vehicle will weigh 300kg.
Sizing the beams for a single-vehicle collision against a ...
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2answers
92 views
Distribution of energy absorption in inelastic collision
Object A has mass $m_A$, and is travelling west with velocity $v_A$. Object B has mass $m_B$ and is travelling east with velocity $-v_B$. The objects collide in a perfectly inelastic collision so ...
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1answer
36 views
How to convert kN/m² into point loads?
I have a concrete steel ceiling. The calculations show the ceiling is designed for 1,5 kN/m² in addition to it's own weight and traffic loads including snow. So I assume I can hang 1,5 kN/m² from that ...
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1answer
21 views
Normalizing the compressive stress to a cylinder
I'm not an engineer but a neuroscientist.
I do research in spinal cord injury whereby a clip is used to clamp the spinal cord to induce a bilateral compression injury model.
My research looks at the ...
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0answers
34 views
Beam analysis - relating deflection equation to pressure force
From regular beam deflection equation and $f=kx$, I ended up getting
$$k = \dfrac{4Ebh^3}{L^3}$$
where $k$ is stiffness, $E$ is modulus, $b$ is width, $h$ is thickness, $L$ is the length. and the ...
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1answer
73 views
How do I calculate how much weight an iron cylinder can support?
I would prefer an equation.
The premise is that I'm trying to calculate how thick an iron cylinder using a screw jack would need to be to support 20kg of weight for engineering class. We haven't ...
2
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0answers
48 views
Compression members with moment to BS 5950-1:2000
According to clause 4.8.3.2 the cross-section capacity for non-slender section is:
$$\frac{F_c}{A_g p_y}+\frac{M_x}{M_{cx}}+\frac{M_y}{M_{cy}}\leq 1 \qquad (1)$$
According to clause 4.8.3.3.1 ...
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1answer
63 views
Stiffness as a function of thickness
Let’s say we have a thin band (made out of PLA, 3D printing material) with a rectangular cross section. In drawing, it would look something like this:
Let’s say a force of 15 N is to be applied from ...
3
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1answer
68 views
Percentage area of steel for a retaining wall - standard formula doesn't make sense to me?
I'm looking at the usual UK/EU standards formula for the reinforcing steel area percentage, in a retaining wall. Essentially in "usual" cases it comes down to 0.13% of the cross-sectional area of Tw (...
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2answers
57 views
Why is the unit for torsional twist in radians?
It's easy to understand the formula for the twist angle in a section due to torsion, and all the units neatly cancel out leaving a unitless number.
It might sound like a very simple question that it'...
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1answer
33 views
Meshing Complex models in abaqus
I'm trying to mesh a model of a morphing wing in Abaqus and have been running into issues. It was recommended that I partition the model into smaller parts, but it seems that the more I try to ...
4
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1answer
50 views
Can secondary beams be supported to columns occaisionally?
If there are secondary beams running between primary beams, and columns support the primary beams, then is it allowable to have the occasional secondary beam pinned to a column? Otherwise it seems to ...
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1answer
161 views
What is the straightest, longest and strongest pole that could be launched into space?
Which of these poles would be straighter and stronger then the others?
These are some poles that are compacted making them possible to send to space. Sending a single solid pole .5km long will not be ...
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2answers
42 views
Max torque allowed on cypress wooden beam
I am trying to calculate the maximum torque that a piece of cypress wooden beam can handle before it snaps or becomes structurally unsound. I know this will depend on the thickness and width of the ...
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26 views
what is the different of these concentrated moment loading case?
what is the different of these concentrated moment loading case?
C is intermediate hing "no moment transfering"
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0answers
26 views
How to identify building types?
In absence of documents(e.g. plan, drawings etc.) how to determine the category of building after building has been erected completely?
See the intended categories of buildings in the attached image.
...
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1answer
38 views
Relation between residual stress and von mises stress calculated by FEA in comercial software
Suppose we do nonlinear structure mechanics computation.
In each time step, we can get the results and can get Von Mises Stress at each node of the mesh. Can we say this number also means its ...
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0answers
16 views
Combining response spectra
I have a question regarding response spectra and its use within dynamic analysis.
Assume that a load combination that a component is subject to is the result of two events: A and B. If each event, A ...
2
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1answer
74 views
What can a licensed Mechanical Engineer do in the civil/structural field?
When I was younger, I had interned in a civil/structural engineering firm specializing in bridges that had many PE civil engineers on staff and a couple licensed mechanical engineers.
Now as a soon-...
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2answers
104 views
Deflection of a cantilever beam composed of separate (not bonded) planks
In the case of a simple cantilever beam having a uniform shape and being loaded at its end - the calculation of the deflection at any point along the beam is well known.
What happens if we split it ...
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0answers
42 views
Assumptions to neglect shear stress in a sectional area
Which assumptions do I need to simplify or neglect the two shear stresses of my stress tensor for comparing two sectional areas in relation to their stability? And do you have any reference for such ...
2
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1answer
83 views
Help with cantilever table top questions
I'm hoping someone can help me with some questions to know whether or not the table can be supported by this design and how to calculate the length of the support runners and the width necessary to ...
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1answer
66 views
Equation of the parabolic suspension bridge cable when the deck mass is known
I'm reading the derivation of the equation of the hanging catenary from Wikipedia:
https://en.wikipedia.org/wiki/Catenary
In the same article the parabolic equation governing the shape of the main ...
2
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2answers
29 views
Is is possible to use singularity function to expresse the horizontal forces ?
I know how to translate torques and vertical forces into singularity functions, but may i also express the horizontal forces with singular function? if yes then what would be that expression?
Here ...
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3answers
125 views
Why aren't there moments in truss bridges?
One of the assumptions we make when analyzing truss structures (method of joints for example) is that all the components are assumed to experience only compressive and tensile forces, not bending ...
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1answer
53 views
Shear forces along a beam using singularity functions
$\newcommand{\a}[1]{\langle#1\rangle}$
As you can see, the left end of the beam is fixed, and a distributed load is applied to the beam. I calculated the shear forces by conventional means, but when I ...
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0answers
32 views
structural radius for strain evaluation - Propeller Design
What is 'structural radius for strain evaluation' in aircraft propeller design?
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3answers
182 views
Minimum thicknesses of an elliptical cylinder pressure vessel
For pressure vessels in the shape of circular cylinders, we can use $\sigma_{hoop}=\frac{pr}{t}$ to find the minimum skin thickness by setting the hoop stress the maximum allowed value, and then ...
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1answer
64 views
Bending equation and max deflection of UDL and multiple point loads
I have a beam, simply supported with 2 points loads and 2 UDLs. The loads are symmetric about the centre of the beam.
I've tried to derive an expression for the moment along the beam and then via 2 ...
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2answers
73 views
Why is this structurally sound?
While visiting Vancouver, Canada recently, I noticed there is a lot of construction for apartments and condos. Attached is a photo of one of many of those sites, and at these sites, I noticed ...
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2answers
45 views
For a building on a slope, should the grounded earth lightning protection be downhill or uphill from the structure?
Would it be best to place the earth protection (the copper spike) for a building on a slope downhill (A) or uphill (B) from the structure? Assume that lightning is most likely to strike at (C), the ...
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2answers
46 views
Solar Array Frame Design / Statics Design Problem
I need some help with a statics design problem. I am tasked with designing a solar panel frame to mount on a building and am the only engineer on staff so I don't have anyone else to ask the simple ...
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3answers
832 views
How does the strength of a square tube depend on the side size?
There are two square tubes of the same length, material and wall thickness, one being 40x40mm, the other 20x20mm. How does their strength against bending compare?
On the one hand, the cross-sectional ...
2
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1answer
31 views
Deflection of a stack of disks under applied force/pressure
I'm trying to calculate the deflection of a stack of metallic disks, when subjected to a force.
In the case of the figure below, representing a valve for a shock absorber, the force is due to a ...
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0answers
41 views
Difference between direction of ramming in hydraulic press?
In Printed circuit board/Plywood lamination Hydraulic Press machines (seen here).
The ramming action comes from bottom in all the machines I saw so far. For such action from bottom, excavation has to ...
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2answers
68 views
irregular shape basement as part foundation for two story timber frame house
A 3 m deep basement has a two story timber frame house above.
They share a side, however both have parts "outside" of the other, as can be seen in the sketch below. The red dash is the basement, ...
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0answers
29 views
20g 11 msec shock
Is there any reliable procedure to estimate a constant acceleration acting on a body (for structural calculation) in case it is subjected to a momentary shock?
I'm assuming it is possible to ...
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0answers
28 views
How to span a 28' gap, preferably with wood
I am building a temporary structure in a windy area (this is for Burning Man). We are essentially using 4x4s that are embedded into the ground (hard clay floor) that are spaced apart by 2x6 rafters. ...
2
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1answer
23 views
Shear strength polymers
I was looking for some shear strength properties of common polymers/plastics.... I have not found any usefull information yet. I know polymers aren't that linear elastic, but I expected to find some ...
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1answer
80 views
What is the engineering term for the gear style articulated arm
You loosen a screw (knob) and then move to the angle you want and tighten.
I need to know what the engineering term for this part is.
Thank you in advance
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3answers
49 views
Excavation near existing structure
I am thinking of building a house with basement next to some existing structures. Are there rules of thumb on how closely/deeply you can excavate next to an existing structure? By moving farther away ...
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4answers
183 views
Is there any need to consider loading sequence in construction stage for structure analysis?
Load sequence in phases can be considered applying the self-weight load only to the story added in the appropriate phase.
Assuming that the material will not go into yield stage ( will always be at ...
