Back to Topic 3.2 — Structural systems
3.2.2Design Technology HL4 flashcards

Classifying structures

Practice Flashcards

Flip to reveal answers
Card 1 of 43.2.2
3.2.2
Question

Frame, shell and solid — what distinguishes them?

Click to reveal answer

Track your progress — Sign up free to save your progress and get smart review reminders based on spaced repetition.

All 4 Flashcards — Classifying structures

Sign up free to track progress and get spaced-repetition review schedules.

Card 1comparison

Question

Frame, shell and solid — what distinguishes them?

Answer

What carries the load. A frame carries it along slender members meeting at joints; a shell through a thin curved surface; a solid through its bulk, mostly in compression.

Card 2process

Question

How can you tell a shell from a frame on a real product?

Answer

Ask what a hole would do. A frame loses one member, which bracing may cover. A shell loses most of its stiffness, because the surface was the structure.

Card 3concept

Question

Why does a rectangular frame need a diagonal brace?

Answer

A four-bar rectangle folds into a parallelogram with no member changing length. A diagonal makes two triangles, and a triangle cannot change shape unless a member stretches or shortens.

Card 4concept

Question

Why is a flat panel not a shell?

Answer

It carries load in bending, which is the weak way. Curvature, a fold or a rib converts bending into in-plane forces, which is what makes a shell stiff.

Track your progress with spaced repetition

Sign up free — Aimnova tells you exactly which cards to review and when, so you remember everything before your IB exam.

Start Free
IB Design Technology Classifying structures Flashcards | 3.2.2 | Aimnova