Basics of Structural Analysis: Difference between revisions
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The strain <math>\epsilon</math> in the filament is due to the different lengths of filaments in bended beam. <math>\epsilon = </math> | The strain <math>\epsilon</math> in the filament is due to the different lengths of filaments in bended beam. <math>\epsilon = </math> | ||
Radius of curvature <math>\frac1R = \frac{\ | Radius of curvature <math>\frac1R = \frac{\partial v^2}{\partial x^2}</math>, and <math>\epsilon_{xx} = -y \frac{\partial^2 v}{\partial x^2}</math>. | ||
== Column == | == Column == | ||
Revision as of 11:42, 20 January 2024
Introduction
Structural analysis using about high school level physics and maths.
Aim to calculate fiberglass cansat structure
Basic theory
Principle of superposition: linearity. Displacement at location Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B} from forces Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle P_1} and </math>P_2</math> located at different positions is calculated as Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Delta_B = \Delta_{BP_1} + \Delta_{BP_2}}
The energy principle: Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle dW = Fd\Delta} giving the total energy as Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle W = \int_0^\Delta Fd\Delta} which is called strain energy. For linear deformation this gives Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle U=\tfrac12 F\Delta} .
Virtual work principle.
Dead loads, live loads, impact loads (impact factor), wind loads.
Equilibrium.
Forces:
- Normal force and axial force (out-of-plane forces, in-plane forces)
- Shearing force Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{V(x)}{x} = -w(x) } . Thus we have Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Delta V =\int w(x) dx } . Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle w(x)} is the intensity of applied (normal?) force.
- Bending moment Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{dM}{dx} = V(x)} and thus Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{d^2M}{dx^2} = -w(x)} .
- Torsion (of a plate)
Plate
Beam
Forces:
- Normal force and axial force
- Shearing force Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{V(x)}{x} = -w(x) } . Thus we have Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Delta V =\int w(x) dx } . Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle w(x)} is the intensity of applied (normal?) force.
- Bending moment Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{dM}{dx} = V(x)} and thus Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{d^2M}{dx^2} = -w(x)} .
Deflection of beams
The strain in the filament is due to the different lengths of filaments in bended beam.
Radius of curvature Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac1R = \frac{\partial v^2}{\partial x^2}} , and Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \epsilon_{xx} = -y \frac{\partial^2 v}{\partial x^2}} .
Column
Column is a vertical beam.