460 likes | 553 Views
To keep size down many pictures and the links on this presentation were not included for the proceedings. If you wish to receive a CD with the full content please contact me at: somers.anthony.a@edumail.vic.gov.au. Materials and Structures. Anthony Somers Ashwood College.
E N D
To keep size down many pictures and the links on this presentation were not included for the proceedings. If you wish to receive a CD with the full content please contact me at: somers.anthony.a@edumail.vic.gov.au
Materials and Structures Anthony Somers Ashwood College Materials Engineering
Materials and Structures • Introduction • Topic Breakdown • Demonstrations and Practicals • Sample Problems • SAC • Textbooks • Careers • Resource CD
Materials and Structures Design and materials combine to make successful structures
Materials and Structures Why is it important? • Tacoma Narrows Bridge
Structural Failures Westgate Bridge • During construction • Two sides not aligned
Westgate Bridge Original design 40000 vehicles 25t max Present day 250000 vehicles 68t max
Structural Flaws Investigating how structures fail……...
Structural Flaws Any concerns?
Structural Flaws Is this a safe work environment?
Materials Price $1600 Price $10,000 Why?
Materials and Structures The success of any structure depends on: • The design of the structure • The materials used in the structure
Materials and Structures Topic breakdown • Study Design • Exams
Materials and Structures Exam breakdown • Forces in Structures (Structure) 31% • Stress/Strain Curve (Materials) 50% • Composites (Steel/Concrete) 14% • Terms 5%
Materials and Structures Main Topics with Presentations • Forces in Structures • Stress/Strain Curve • Composites
Forces in Structures Understanding • Types of loads • Forces in structure elements
Forces in Structures There are five different types of load • Tension (stretching) • Compression (squashing) • Shear (sliding) • Bending • Torque (rotating) Load Demonstration
Forces in Structures Force type analysis in structures Construct structures
Stress/Strain Curve Many terms: • Stress • Strain • Young’s Modulus • Strength • Stiffness • Elastic • Plastic • Brittle • Tough • Yield Point
Stress/Strain Curve Stress and Strain • Killer Pythons and Snakes Which is stronger?
Stress/Strain Curve Stress and Strain • Used to compare materials of different dimensions • Stress = Force/Area • Strain = Change in Length/Original Length
Stress/Strain Curve Stress Strain
Stress/Strain Curve Types of Tensile Testing Stress Stress Strain Strain Increasing weight Measure strain Constant speed Measure stress and strain
Stress/Strain Curve Tensile Test Video
Stress/Strain Curve Material Properties • Plastic/Elastic • Brittle/Tough Demonstrate with silly putty Available from CSIROSEC
Composite Materials • Second material inside first to increase toughness • Carbon fibre composite, reinforced concrete, fiberglass • The reinforcing spreads the energy of the crack Toughness Demonstration
Sample Problems Forces in Structures For stability: Forces: R = F1 + F2 Torque about R: F1x1=F2x2 R x1 x2 F2 F1
Sample Problems Forces in Structures x Fs 30° Fw Beam weight 60° Strut Load Weight
Sample Problems Composites
Assessment SAC – Great for data analysis • 2007 SAC
Materials and Structures Textbook Analysis
Textbook Analysis Jacaranda • brief on force in structures • covers stress/strain curve and composites well
Textbook Analysis Nelson • force in structures well covered • stress/strain curve OK confusing order • composites very brief
Textbook Analysis Heinemann • force in structures very brief • stress/strain curve very well covered • composites very well covered
Careers What do materials engineers do? • Select appropriate materials • Develop new materials
Careers What do materials engineers do? • Failure Analysis • Test materials
Careers What do materials engineers do? • Predict material lifetimes
Materials and Structures Careers – Monash University • Materials Engineering More information: • Materials Engineering Brochure • www.monash.edu.au/materials
Materials and Structures Anthony Somers somers.anthony.a@edumail.vic.gov.au • If you want data for data analysis SAC • Post on Edulists (edulists.com.au) • Experiment ideas to be passed on
Structural Failures Tacoma Narrows Bridge (wikipedia) • Sides of bridge solid, catch wind • Deck of bridge too light