Bellwork What are the three ways a bridge can fail? Buckling Snapping Torsion

Bridge Building 11/19/13

Shapes Recap Triangles – Very good Circles – Good (small scale only) Squares – Okay (not ridged)

Tips For Building Bridges Start with a beam bridge Make sure it is a least 29 cm to cover the gap Make sure the glue is DRY (overnight) Make the deck flat for the car with a hole in it Make the ends strong and beam girders go all the way across.

Notes on Bridge Project Beam Bridge: (all bridges) Beams should go all the way across Have strong ends Ajo Way & I-10 Tucson, AZ

Notes on Bridge Project Truss: start with beam bridge the truss structure has to aid in the supporting the load 3.5 cm clearance AZ Route 88 – Canyon Lake, AZ

Notes on Bridge Project Arch: start with beam bridge the arch structure has to aid in the holding the load the abutments need to be on the table London Bridge Lake Havasu City, AZ

Navajo Bridge Marble Canyon, AZ

Mike O'Callaghan–Pat Tillman Memorial Bridge Lake Mead National Recreation Area

Notes on Bridge Project McPhaul Bridge Yuma, AZ

Notes on Bridge Project Cameron Suspension Bridge Cameron, AZ

Notes on Bridge Project Royal Gorge Bridge, Cañon City, CO

Notes on Bridge Project 101 & 63rd Ave cable-stay Bridge Glendale, AZ

Notes on Bridge Project Suspension and Cable Stayed: start with beam bridge deck can not be more then 30 cm towers need to be on the table placement of the towers string needs to aid in holding the load string to the weights is not counted as the length measurement can use anchor weights, 10 lb each side

Tips For Building Bridges Start with a beam bridge!!! Optional - You can decorate with markers, color pencils or crayons (but NOT paint) Bonus for max load in each category –Beam –Truss / Arch –Suspension / Cable-stayed

Bridge Testing The center of the deck needs to has a hole (1.0 cm diameter) for the load tester Each bridge will be weighed before the testing Each group will add mass (0.50 or 1.0 kg) to the bucket Need to wait a few seconds between each added mass A max load is when there is buckling or snapping of the bridge

Today Finish Mini Bridge questions Print group name(s) on list Get two manila folders Work at the desks NOT in the lab area At the end of class Place bridge in period cabinet Return materials Clean up – glue, scrapes, etc. (last 5 min.) Yes, you can work on the bridge outside of class and over the weekend Need to be working on the project!

Mini-Bridge Questions: (Use complete sentence for full credit) 1.What worked well for your design? 2.How did you improve your design over the trials? 3.What problems did you encounter? 4.Where did your bridge(s) collapse? 5.How did this activity help you with the project that is due on next week?

Bridge Building 11/19/13

Bridge Building 11/19/13 Millau Viaduct - Millau, France