Questions tagged [structural-analysis]
Structural analysis is the determination of the effects of loads on physical structures and their components. Structures subject to this type of analysis include all that must withstand loads, such as buildings, bridges, vehicles, furniture, soil strata, prostheses and biological tissue.
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Can I reduce the column moment due to beam, by setting the beam end to pin?
I have a structure, which contains only frame elements ( beam and column).
From what I know, if I apply point load at the columns on both left and right hand side,and if the beam-column joint is ...
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Why the design of continuous beam is always more economical than beam with supports?
Assuming that I have a beam that spans across a few supports. I can design the beam as a continuous beam (a beam that is loaded and has more than two supports), or individual beams that each encompass ...
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Interpretation of shear flow/shear center of L-profile
I have calculated the shear flows and center of an L shaped profile. I assume they are correctly calculated (I followed the same steps as during the lectures for an I shaped profile). However, I have ...
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Why do stress concentrations really occur?
From doing some research I've learned that internal stresses inside an object can "concentrate" on sharp edges, as shown in the above picture. For that reason we often make fillets so that the change ...
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How to derive Equivalent Static Load for irregular structure modeled with FEM?
Building codes such as the Uniform Building Code (UBC) or International Building Code (IBC) require the determination of Equivalent Static Lateral Forces in order to compute $P-\Delta$ effect and to ...
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Is pin column-beam joint always have less moment, more deflection compared to fixed joint?
I am referring to the answer here:
It seems that on a simple structure
(The diagrams on the left the images below have fully-fixed connections, while on the right the columns are pinned connections ...
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Why does a continuous beam have less deflection than a pair of simply supported beams?
Inspired by this question, and also this answer to a separate question.
I have two beam models, one with two independent spans (a full hinge), another is a continuous beam over both spans (only ...
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Modeling the structure vs FEM
When you model the structure to be analyzed with a structural analysis program, indicating the beam elements, shell elements, nodes, rigid links etc... The analysis is still called Finite Element ...
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How do you check a weld for applied moment?
I have a single angle connected to a double angle via a 3/16" weld
I know there is a factored, applied moment at that connection. I would like to ask how I can go about checking the capacity of this ...
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Mathematical representation of hinge and pin connection
Following on from this answer, I am reading about the difference between hinge and pin connections here, and I don't quite understand about it. I think I would need to see the mathematical ...
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Truss manufacturer drawings unclear
I am currently looking at a set of truss layouts produced by our truss manufacturing partner for a residential building project. I have reason to believe these layouts are generated using Alpine (...
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Properties of an hexagonal shape vs round tube shape
In a bike frame build, are there any differences between hexagonal cross-section tube instead of the typical round tubes?
Assuming that both are made from the same aluminium alloy and have the same ...
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What does "beam end release" actually mean, and how it is modeled in mathematical terms?
I am reading a document about beam end release here:
An end release will allow either or both ends of a beam element to
rotate about or translate along one or more of the local axes of the
beam....
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Stiffness Method FEM - Slender Members
If a member is very slender then its length will be large compared to its cross-sectional area. I've heard and read that slender members can potentially cause the stiffness matrix of a beam/frame ...
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How to simplify a truss bridge diagram?
Hello I have this truss structure question. I understand that we need to determine the zero-force members first so that we can simplify the diagram. But I am not sure which one that I need to ...
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Can a horizontal foundation safeguard against earthquakes?
I have not taken any course in civil engineering. What I was taught was that a broad base would prevent something from toppling. So it makes me wondering instead of nailing the foundation of a ...
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Can a crisscrossed metallic skeleton resist earthquakes for buildings?
To follow up with my previous question on the seismic design of buildings, I would like to ask if it makes sense to support buildings with strong thick 'crisscrossed' metallic frames.
I have the ...
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Estimating dynamic load from human body
I want to build myself a pull-up bar. I am confident enough that I can guesstimate how much material I need for it to be strong enough, but this time I would like to challenge myself to properly ...
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Reaction force on a beam
I have the following problem most of which I have calculated but have a difficulty with the beam under angle. The angle is 56,30 degress. I just cannot figure out how the forces there are acting - the ...
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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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L beam - Strange result
I have the following system (at P and Q there is a ball joint; the length of L beam is l; the PB and PA forces are applied at l/2 and are known; Fz is not zero and is known):
The system has 0 degrees ...
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How to calculate residual strength of a corroded structure from their stress values?
Currently, I have an actual entire corroded bridge model in the FEM analysis in Abaqus
I want to estimate the residual strength of this bridge due to corrosion
from the output results in the Abaqus, I ...
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How to calculate monosymmetry index of an unequal angle? [closed]
I saw some formula involving integration. Is there a straightforward formula to calculate this instead given b, d, t and alpha angle between x-x and u-u axis?
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Which would be the most rigid?
I'm trying to resolve a theoretical problem.
If I have 2 steel boxes made from the same gauge steel (3mm stainless steel) & one is 7 meters by 2 meters by 2 meters & the other is say 30% ...
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Shear coefficient for an I-Beam
I’m trying to analyze the bending of an I beam using the Timoshenko beam equation and I can’t seem to find the value for the shear coefficient anywhere.
Surely someone must’ve done the work (given how ...
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How is any kind of structural reliability achieved if the probability of annual wind speed exceedance is 0.02?
Above is the definition of fundamental basic wind velocity from Eurocode 1. According to its instructions, wind loads on building are supposed to be calculated based on this velocity. It says that ...
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Conjugate beam (M/EI)
I dont understand how the diagram of M/EI of conjugate beam drawn , can someone explain about it ?
According to conjugate beam theorem , i know that the M/EI represent the w(x) , which is force per ...
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Why/how normal shear stress is zero in thin-walled beams?
Please explain how the normal shear stress (shear stress normal to the cuve, C, defining the cross-section of a thin-walled beam) is zero. I have attached a screenshot from a book which says that the ...
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qualitative influence line of pinned support
For the highlighted part , why we need to replace the support at A with a roller guide ? We could see at A , it's a pinned support , right ?
Pinned support will resist horizontal and vertical ...
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Proving the advantage of a composite beam
The textbook that I'm following for studying bending stresses in beams, states that - "Engineers purposely design beams in this manner (composite manner) in order to develop a more efficient ...
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Trying to shed some weight on my design, any thoughts?
I am trying to design a lifting mechanism and I would love some insight/opinions as to how I can shed some weight off it.
The current weight I have for my mechanism is 187.5kg, however, this is ...
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What will the reaction forces of a support be in case of an angled cable
If a cable is attached to a support on each side, and there is a load acting on it somewhere along its length.
Is there going to be a vertical reaction force only if the the cable is angled?
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max shear act on point
Why we need to consider only 3 cases when we want to find the max positive shear ? IMO , We know that the max shear will only occur when the 67.5kN act on B , am i right ? There is no need to consider ...
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Economical difference with high-pressure vessel design pressures for fixed volume
Suppose space is not an issue and I need a fixed volume of compressed air (for storage), say 1m³. Is it more economical to manufacture a thick-walled vessel but with a smaller volume or a thin-walled ...
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Earthquake time history analysis
Time history analysis of earthquakes for structures, is a NON-LINEAR dynamic method correct?
Then why is there also something called "LINEAR response history analysis"? What is the difference of this ...
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