T1-L19: Bridge Construction — Completion & Test Preparation

Learning Intention

We are learning to complete our bridge construction and prepare for load testing.

Success Criteria

I can complete cross-bracing and deck installation
I can apply finishing techniques to strengthen joints
I can predict my bridge's load capacity
I can document my completed bridge

✎

Do Now

Look at your bridge — list 3 things you still need to complete.

#	Task to complete	Priority (High / Med / Low)
1
2
3

📚

Key Vocabulary

Standard: Fill in the definition. | Support: Definitions shown in grey — read and copy into your folio. | Extension: Use each term in a sentence.

Term	Definition	Use in a sentence (Extension)
Prediction	An informed estimate based on evidence and reasoning
Hypothesis	A testable statement: “If… then…”
Load capacity	The maximum weight a structure can support before failure
Structural failure	When a structure breaks or collapses under load
Reinforcement	Adding extra material or support to strengthen a structure

⚠

Activity 1: Safety Reminder

Quick review — tick each rule to confirm you remember.

	PVA glue on skin — wash immediately
	Craft knives only with teacher permission
	Workspace clean and organised
	No eating or drinking near materials
	Report all accidents to teacher

✅

Activity 2: Self-Assessment Checklist — Where Am I? (Folio p. 79)

Tick each item you have completed. Use this to prioritise your work today.

✔	Milestone	Status / Notes
	Design brief complete
	Research and sketches done
	Side trusses built
	Cross-bracing installed
	Deck attached
	All joints reinforced
	Production log updated
	Ready for testing

💡 Priority Guidance:

0–3 ticks: Focus on trusses and cross-bracing first
4–6 ticks: Complete deck and reinforce joints
7–8 ticks: Final checks and prediction writing

🔨

Activity 3: Cross-Bracing (Folio p. 79)

Cross-braces connect the two side trusses to prevent twisting. Follow these steps:

Step	Instruction	Done? Notes
1	Measure the gap between the two trusses
2	Cut or select cross-brace sticks to the correct length
3	Glue both ends of each cross-brace
4	Press firmly and hold
5	Space cross-braces every 3–4 cm along the bridge
6	Check for twisting — bridge should sit flat and square

Number of cross-braces added:

🛠

Activity 4: Install Deck (Folio p. 80)

The deck is the flat surface where the load will sit.

Lay sticks flat across the top, perpendicular to the bridge length
Glue each deck stick to the cross-braces below
Place sticks edge to edge — no gaps

Notes on deck construction:

💪

Activity 5: Reinforce Weak Joints (Folio p. 80)

Inspect every joint on your bridge. Strengthen any weak points.

Check every joint — are any loose or cracked?
Add extra glue to weak joints
Double up critical spots (add an extra stick alongside)
Focus on the bottom chord and end supports

📏

Activity 6: Final Alignment Check (Folio p. 80)

Place your bridge on a flat surface and inspect from three angles.

View angle	What to check	Any issues? How did you fix them?
Side view	Trusses are straight, no sagging
End view	Trusses are parallel, not leaning
Top view	Deck is flat, no twisting

📝

Activity 7: Production Log & Prediction (Folio p. 81)

Detail	Your response
Final photo / sketch:
Bridge label:	Name: Class:
Production log update:

🔮 My Prediction

I predict my bridge will hold kg because:

🔵 Support — Completion Assistance

Focus on the basics — complete these three things first:

Trusses: Make sure both side trusses are glued and dry
Cross-bracing: Add at least 4 cross-braces between the trusses
Deck: Lay sticks across the top for the load to sit on

Prediction scaffold:

“I predict my bridge will hold ___ kg because ___.”

Word Bank

cross-bracedeckreinforcealignment predictionstructuralload

🟠 Extension — Analysis & Reflection

Calculate bridge weight: Weigh your bridge (if scales available) or estimate.

Bridge weight (g):

Target efficiency ratio:

Peer assessment: Inspect a partner’s bridge. What are its strengths and weaknesses?

Written reflection: If you could start over, what would you change about your design?

Research: What is the world record for a craft stick bridge load? How does it compare to yours?

🎫

Exit Ticket — Reflection

1. Predict: How much weight (in kg) will your bridge hold? Explain WHY.

2. What is the ONE weakest point on your bridge? How could you improve it?

Success Criteria	Got it 🟢	Nearly there 🟠	Need help 🔴
I can complete cross-bracing and deck installation	●	●	●
I can apply finishing techniques to strengthen joints	●	●	●
I can predict my bridge's load capacity	●	●	●
I can document my completed bridge	●	●	●