Structure

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Introduction

Structural Scaling Rules

• Mass ~ x³
• Surface area ~ x²
• Tensile/compressive/beam strength ~ x²
• Beam stiffness ~ width * depth² (~ diameter³ for circular rod)
• Beam deflection ~ force * length³ / stiffness
• Strength of a beam ~ material_strength * width * depth² / length
• Stress in beam ~ force * length / (width * depth²)
• Cantilever deflection = 16 * double_end_support_deflection (= 128 * double lock?)
• Torsional stiffness of a circular rod ~ diameter⁴
• Torsional stiffness of a rectangular element ~ short_edge³ * long_edge
• Torsional deflection ~ torque * length / stiffness
• Support of cantilevered member needs area/strength ~equivalent to cross-section of beam. Same with spliced beams. = more bolts than you might think.

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