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.
296
questions
-1
votes
1answer
21 views
Elastic waves in very thin plate
Elastic waves in structural elements are described by
\begin{align}
\rho \frac{\partial^2 u}{\partial t^2} &= (2 \mu + \lambda) \frac{\partial^2 u}{\partial x^2} + \mu \left( \frac{\partial^2 ...
1
vote
1answer
15 views
For arc-length method in nastran, how to analyse post-buckling behaviour with load decrease
I am currently trying to model the buckling behaviour of a cylinder using sol 400 nonlinear static analysis using Nastran. I am using the arc-length (modified Riks) method as apparently it can ...
-1
votes
0answers
23 views
Structural response and Reinforcement in shell elements when using SAP2000
Aqueduct is hydraulic structure compose of bottom slabs resting on sidewalls.
Bottom slabs acts as one way slabs while side walls act as beam , as per our conventional design assumption. But when it ...
1
vote
1answer
35 views
Understanding Bending and Twisting Moments in a Plate
I am trying to understand Kirchoff Plate Theory and I am unable to understand the difference between bending and twisting moment for a plate. In a beam structure, if moment is along the axis of the ...
0
votes
1answer
28 views
Free pre-processor for Nastran?
I want to do a non-linear analysis (possibly SOL 400) on Nastran. I used PyNastran (python module) to set-up the BDF file for a Linear buckling analysis (sol 105). However I feel like it might be too ...
1
vote
1answer
20 views
Determining If A Test Article Is Suitable For X RAY Following Shock Testing?
I am interested in putting a small (3"x3"x2") assembly under X-ray, following a shock test, in order to evaluate failures of an internal ceramic piece. Unfortunately, this assembly utilizes quite a ...
-1
votes
1answer
55 views
Could a bolt this size actually be used on a project?
could there ever be a structure that would require something like this?
0
votes
2answers
46 views
Deflection In Multistory Structure
When analysing and designing a structure for the serviceability limit state the deflections of each beam must be found. When considering a multistory rigid jointed structure (as below) and applying ...
-1
votes
0answers
10 views
What effect as a remote anguar torque on a central axis?
Here is the problem:
Consider a central axis of rotation of a system which has an inertial momentum. Some force applied far from the axis could trigger a rotation of the axis, and three main ...
3
votes
1answer
49 views
Failure modes of a zimmer frame
I've been asked to modify an existing zimmer/walking frame for a tall person. Bashing the bits of metal is the easy bit, just use tube to make longer legs to replace the original short removable ...
1
vote
0answers
14 views
Finding reactions of a continuous beam
is it possible to find all the support reactions of this continuous beam using fourth order equation without using principle of superposition?
0
votes
1answer
44 views
Designing PVC structure
I am an electrical engineering student that wishes I could have taken some civil engineering courses. Anyways I'm trying to design a pvc structure that I will use as a somewhat complicated room ...
-1
votes
1answer
26 views
Predict egg drop outcome in random container
What elements affect the outcome of a raw egg drop in a random container?
I’ve considered friction, mass, size of container, size and type of padding. Are there other elements?
3
votes
1answer
25 views
Truss analysis of internal forces in members
I am trying to calculate the internal forces and their nature in this truss, however, I cannot seem to do so as both the method of joint and the method of section do not work. I think this is because ...
0
votes
1answer
34 views
Beam with internal hinge - Reactions help
can someone explain why the highlighted area (at Mb=0) is - 5x2 and not positive? Since the rest of the loads(and the rest of that very same load) pointing down were documented with a +,
I dont ...
0
votes
0answers
29 views
Calculate the second moment of area around y-axis
In an exercise on my engineering class, I have to calculate the moment of area around y-axis (the horizontal one). There is a very small (negligible) gap at the middle of the semi-circular arc, and ...
1
vote
1answer
37 views
What criteria must apply for torsional effects on this beam to be ignored in calcs?
I'm interested in how to work out whether torsional effects can be ignored or not, in calculating the adequacy of a given steel beam in the following idealised eccentric scenario.
Or, equivalently, ...
1
vote
1answer
41 views
Mounting outdoors camera using aluminum 5052
I designed a simple U shape 2mm sheet metal bent mount for a 4kg outdoors CCTV camera. The mount was accidentally produced from 5052-H32 Aluminum instead of 6061-T6.
Is it common to use 5052 ...
0
votes
2answers
81 views
2D- Truss Member Analysis
I am a graduate student trying to sharpen the direct stiffness method skills. However, I am stuck at the beginning.
The problem is given in the image.
Can someone help me to write down all the nodal ...
0
votes
0answers
17 views
Determining the minimal needed wall thickness between two bores in a control block
Given a control block of simplicity with only two bores. These two bores could be parallel or just could be very close to each other at a specific point in the control block.
The material of the ...
0
votes
1answer
51 views
Orthogonal to Orthoradial reinforcement
Most of finite element calculations are performed with an orthogonal mesh (Cartesian coordinate system). From this calculation, we get two values of required steel area per linear meter: $Ax, Ay$ ($cm^...
0
votes
1answer
32 views
Consequences of Inextensibility of an in-plane line in Euler-Bernoulli Beam Theory
The Euler-Bernoulli beam theory is based on the hypothesis that the beam deforms such that a straight line normal to the beam axis before deformation remains
inextensible
straight
normal to the beam ...
0
votes
2answers
58 views
Structural Analysis of an RC plane in flight
I am working on structural analysis of an RC plane in a symmetrical maneuver. There are two types of loads on the structure a) aerodynamic loads and b) inertial loads.
I have determined the ...
0
votes
2answers
85 views
Second Order Elastic Analysis
When analysing a structure using traditional methods (e.g. Hardy Cross, Slope Deflection, Force Method, etc.), it is a first-order elastic analysis. My question is, how would one analyse a statically ...
0
votes
3answers
39 views
Maximum spans in multi-level building
Is it possible to build a building with 3 levels, with the 2nd and 3rd levels having areas with clear spans (no columns) of 130 ft length and 85 feet width? There can be columns outside of this clear ...
2
votes
0answers
51 views
How to compare two acceleration sensors side-by-side?
I have a single axis analog capacitive acceleration sensor (from PCB Piezotronics) which is very reliable but expensive. Now I need more axis, unfortunately can not afford buying anymore. So I have ...
0
votes
1answer
52 views
Modification of Beam Equation for Thin Sheet
I am trying to determine the modulus of elasticity (Young's Modulus) for a rigid paper sheet. The issue I am having is that my results for the Young's Modulus change depending on what orientation (...
0
votes
0answers
93 views
Deflection Of Beam In Structural Rigid Jointed Frame
This is a recommended follow on to one of my previous questions. It was stated that I could find the deflections of a beam by idealising it as a simply supported beam and then calculating accordingly. ...
0
votes
1answer
73 views
Deflections Of Statically Indeterminate Structures
When analysing and then designing a rigid jointed, statically indeterminate structure, I can solve for all the forces and moments using the Hardy Cross (Moment Distribution) Method.
However, I am ...
0
votes
2answers
49 views
Determination of Young's Modulus for use in Analysis
I am writing a finite element code for my final year project of BS Mechanical Engineering. The geometry is an integration of several parts composed of different materials. I don't have exact values of ...
0
votes
1answer
49 views
Concept on two-force member
I have some homework question that i require some help understanding.
1) For the first question highlighted in red (referring to diagram viii), I know for sure that reactions at the supports is ...
1
vote
0answers
41 views
Analysis Of Planar Frame Using Hardy Cross Method (Moment Distribution) With Sway
The image shown below is a sketch of the structure/frame that I am attempting to analyse using the Hardy Cross (Moment Distribution) Method. I need to find the bending moments, axial forces and shear ...
0
votes
2answers
59 views
Pin joint system displacement question
A pinned system comprising bars of the same material and cross-sectional area is subjected to a vertical load P.
I am required to form a relationship between FAB and P.
The first part of the ...
2
votes
2answers
153 views
Can a speedbump safeguard a pipeline located below?
Recently I noticed a concrete speed bumper created near my parking. On enquiring the purpose, the committee who took the decision told me that the purpose of the bumper is to safeguard an existing ...
0
votes
1answer
49 views
How do I calculate the compressive strength of a wall?
I literally just have a thin steel wall that stands vertically with a load on top. The thin edges of the wall are oriented vertically with the load applied on top of the top thin edge, with the large ...
0
votes
1answer
42 views
Is Belytschko beam defined for 3D or 2D?
from the paper in this link , which is the Belytscko beam. I could not figure out if it is a 3D beam or a 2D one.
if you don't have access to that paper, please check the page 73 on this link.
what ...
0
votes
2answers
54 views
How deep do you have to check for problems underneath a building site?
When you're putting up a new building, you have to check the soil underneath for stability. How deep do you typically have to check? What's the extent of your "due diligence" when ensuring that a ...
0
votes
1answer
60 views
Aluminum tube vs steel
Our question is what size and alloy aluminum tube can be used to replace steel tube in a vertical load application. Our current spec is 1.5” OD STD steel tubing 7 feet long. We will use 6 poles ...
1
vote
2answers
73 views
Design a part to straighten moment and reduce torsion
I have a configuration with two bolts and a point of force application (see figure).
I understand that, if perfectly rigid, the two parts depicted in the figure will behave identically in how they ...
0
votes
1answer
40 views
Ball and Socket Wheel Concept
I am sure you all remember those prehistoric computer mouses that had a ball under it. I'm looking for any points and tips on how to create a ball and socket wheel that has an almost frictionless ...
1
vote
1answer
37 views
Self Weight in Moment Distribution (Hardy Cross)
When applying the moment distribution method also known as the Hardy Cross method, how do I take into account the self-weight of columns? In the case of the beams, I can just apply the weight load ...
1
vote
3answers
100 views
Structure analysis
I am currently designing a setup for an experiment which involves loading a weight to its extension arm, and by design this structure is not bolted to any surface so its free to move. I need to ...
2
votes
2answers
128 views
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 ...
0
votes
1answer
76 views
Analysis of Machine Frames With Cut Outs
I have a structure that is used to support two shafts which are carrying relatively high loads. It is composed of two columns and a "shaft supporting block" in the centre (almost acting as a beam). ...
1
vote
1answer
36 views
Dependency between load capacity for reinforced concrete slab and thickness
How does the load capacity for a reinforced concrete slab depend on the thickness of the slab?
Example:
Let's suppose that we have the following constants:
concrete quality (including the maximum ...
1
vote
2answers
42 views
Parallel Axis Theorem for x and y Shift
I have a quick question about the parallel axis theorem.
Let's say I have a box-like object rotated about the following pivot point
I was wondering, by applying the parallel axis theorem, would the ...
0
votes
3answers
58 views
Why not a reverse bending in the slab?
When I'm looking at images / videos about the load supported by reinforced concrete slabs, I always see a compression at the top of the slab in every point that varies from the center to the edges:
...
0
votes
1answer
95 views
Looking to design a cantilever support to hold up an 80kg projector
I need to make a support (preferably metal) for a projector to be fixed on the wall. The projector size is:
Width: 0.7m
Length: 1.1m
Weight: 80kg
If anyone knows how i can solve this please let me ...
2
votes
2answers
70 views
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 ...
0
votes
1answer
30 views
Stopping Force of Irregularly Shaped Object
I have a quick question about the force needed to accelerate/decelerate an irregular object.
Lets say I have a 3D object with the following general shape,
This system is in general a gripper (gray) ...
