Static Deflection of a Straw Tube under Gravity

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Static Deflection of a Straw Tube under Gravity
Definitions

• Searing Stress/Shearing Strain
• Density of a Straw
• g Acceleration of Gravity
• T Longitudinal Tension Applied to a Straw
• Cross Sectional Area of a Straw
• Y(x) Transverse Displacement
• X Position along the Straw

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For Small Displacements
?2Y _ _??g__ ? ?2x T ??
The Solution for a Length, 2L, with fixed
Positions at ?L
Y ? (x2 L2)
Displacement at the Center is
Y - ?L2 _ _??g__
T ??
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Deflection vs Applied Tension
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Resistive Straw Lay-up
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The Construction Fixture
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Pressurization Manifold for Epoxing