teacher development program bringing schools and engineering …€¦ · bringing schools and...

PRESENTATION 210 MARCH 2015

HUNTER VALLEY GRAMMAR SCHOOL

Teacher Development ProgramBringing schools and Engineering together

Teacher Development ProgramBringing schools and engineering together

• Introduction

• Drop Box

• Civil Structures – HSC Module 1• Engineering Mechanics• Engineering Materials• Communications

• Exam questions Q and A

• Refreshments

• Q + A and Networking

• Close

Teacher Development ProgramBringing schools and engineering together

• Introduction

Paul Reynolds – BEng (Mechanical), Chair of Education Subcommittee for EA

• EA to be your link with the Engineering Profession / Industry• These forums provide important networking opportunities with other teaching

professionals• We want to assist in providing exciting ways of presenting concepts with real

world examples and application• We encourage a link of support with exam assessors• We would like to make clear the pathways to engineering that exist for the

student- Professional, Trades, VET

• WE AIM TO BE A FACILITATOR IN SUPPORTING YOU.

Teacher Development ProgramBringing schools and engineering together

Engineering Studies 2015

Teacher Development Program

Term WeekDate (week beginning)  Year 11 Preliminary Modules Year 12 HSC Modules Venue

1 3 Feb‐09 Engineering  fundamentals MerewetherHigh school

7 Mar‐09 Civil structures HVGS

2 3 May‐04 Engineering products TBA

7 Jun‐01 Personal and public transport TBA

3 3 Jul‐27 Braking systems TBA

Function TBAAugust Engineering week Networking witn UON and TAFE

3 7 Sep‐04 Aeronautical engineering TBA

3 Oct‐19 Biomedical engineering TBA4

7 Nov‐16 Telecommunications engineering TBA

Teacher Development ProgramBringing schools and engineering together

• Drop box• Creation of the “ENGINEERING STUDIES RESOURCE CENTRE” on Dropbox.• Teachers and Engineers Australia to share and communicate useful resources.

Teacher Development ProgramBringing schools and engineering together

CIVIL STRUCTURESDavid Sparkes MBT (UNSW). BE(Hons 1) FIEAust - Engineers Australia Education sub committee.

- Principal Structural Engineer at GHD- Conjoint Associate Professor UON

• Historical Developments of Civil Structures• Engineering Mechanics

– Trusses– Flexural members– Stresses

Teacher Development ProgramBringing schools and engineering together

• Historical Developments

How do they stand up?• They are all Vertical Cantilevers

9

Teacher Development ProgramBringing schools and engineering together

• Engineering Innovation in Civil Structures and their Effect on People’s Lives

• Large buildings have allowed for apartments and businesses to work in better environments.

• Bridges allow people to cross water ways easily and quickly.

• Impacts of bridges include: • More direct travel across waterways, gorges • Quicker travel times • Less fuel used in traveling, cheaper • Job opportunities in design and construction • Pylons may disturb waterways • Negative impact on boating

Teacher Development ProgramBringing schools and engineering together

• Construction and Processing Materials used in Civil Structures Over Time• Timber • Stone – Strong in compression but heavy • Cast Iron • Steel – Corrodes, strong in tension and compression • Concrete – artificial rock – relatively strong in compression

• Environmental implications from the use of materials in civil structures• Timer – Deforestation • Stone – Needs to be quarried, cut, transported • Steel – Pollutants from smelting • Concrete

Teacher Development ProgramBringing schools and engineering together

Trusses

Teacher Development ProgramBringing schools and engineering together

Teacher Development ProgramBringing schools and engineering together

• Truss Analysis – Pin jointed frames.• No transfer of bending at the joints. Axial forces only• (1) Method of joints• This involves working around the truss, solving one joint at a time to find the

axial forces in each of the members.• This method requires the understanding of the sum of vertical and horizontal

forces = zero. It usually requires the application of trigonometry and simultaneous equations. (The first two equations of equilibrium)

• The concept of axial forces in a member (No bending)

Teacher Development ProgramBringing schools and engineering together

• (2) Method of sections• This involves cutting the truss at a discrete location in order to fint the forces in the

members at the particular cut. • This technique required the understanding of the theory of moments about a point =

zero. (The third equation of equilibrium)• The concept of axial forces in a member (No bending)

Teacher Development ProgramBringing schools and engineering together

• Simple beam Analysis – Concepts of flexural (bending) actions.

Teacher Development ProgramBringing schools and engineering together

• Shear force and bending moment diagrams• Here is a beam (top), with the corresponding shear force diagram (middle), and

bending moment diagram (bottom) subject to a point load

Teacher Development ProgramBringing schools and engineering together

Shear force and bending moment for a beam subject to a uniformly distributed load.

Teacher Development ProgramBringing schools and engineering together

• Concept of shear force and bending moment

• Sum of vertical forces = zero• Sum of moments = zero

• Satisfy equations of equilibrium

Teacher Development ProgramBringing schools and engineering together

• Bending stress induced by point loads only

Teacher Development ProgramBringing schools and engineering together

• Stress and StrainShear Stress• Shear stress occurs when you apply shear force. • Eg. If a bolt is supporting a load perpendicular to the bolt of 10kN, and it has a

diameter of 10mm, what is the shear stress?

• Shear stress = 127MPa

Teacher Development ProgramBringing schools and engineering together

• Yield stress, Proof stress, Toughness, Young’s modulus, Hooke’s law, Engineering applications

• Yield stress occurs when there is an increase in strain without an increase in stress.

• Proof stress is the amount of stress necessary to bring a permanent strain in the material.

•• Toughness is a measure of the ability of a material to absorb energy.

• Hooke’s law is , it calculates Young’s modulus of elasticity.

• Factor of Safety• A factor of safety is how many times stronger the material or structure is than it

needs to be.

Teacher Development ProgramBringing schools and engineering together

Teacher Development ProgramBringing schools and engineering together

• The study of a Higher level of Mathematics is very important for carrying out engineering calculations.

• Civil (structural) engineering is about modelling the physical world to understand it’s behaviour by the use of applied mathematics.

• Calculus, for example, is just one key part of mathematics that is used for determining the bending moment and shear forces ( and therefore stresses) in structures.

• Their accurate calculation is very important in the analysis (understanding forces) and design (sizing elements to withstand the forces).

• Manual (hand) calculations is still very much used and taught in 3rd year engineering degrees. It allows simple checking of output of computer analysis for sensibility and errors.

Teacher Development ProgramBringing schools and engineering together

For the simple beam with a distributed load (w) shown, the shear force at C is taken as:

Teacher Development ProgramBringing schools and engineering together

Teacher Development ProgramBringing schools and engineering together

Teacher Development ProgramBringing schools and engineering together

• Calculus and the use of Differentiation and Integration

Teacher Development ProgramBringing schools and engineering together

• Engineering Materials

Michael Van Koeverden

Teacher Development ProgramBringing schools and engineering together

• Engineering Materials-One Civil Structure (Bridge)

..

.Eng. Syllabus Areas:• H1.2- Diff b/w mat

props & selection,• H2.1- Determine

mat props and uses• H4.1- Tech changes

in Eng.

Teacher Development ProgramBringing schools and engineering together

Material Interactions-• Piles- Concrete / Soil• Steel reo / concrete• Acid-Sulphate Soils

Concrete Structural Properties•Compressive Strength at 28days•Cover to reinforcing steel- corrosion•Construction quality- variable?•Impossible to repair piles- cost $

Teacher Development ProgramBringing schools and engineering together

Cast-insitu: Tremmie concrete(E.g. S40MPa/20mm max

agg/180slump concrete)– Place concrete onto concrete– Design life long but $ cost high– Construction quality &

workmanship critical- one chance only to get right !

Tremie pour

1 - 2m

How does Tremmie Concrete work?

Teacher Development ProgramBringing schools and engineering together

Cast-insitu:– Tremmie concrete

• Cost of replacement/repair ?• Investigation / testing

Teacher Development ProgramBringing schools and engineering together

Driven Piles:– Precast concrete (Steam

Cured)• Conventional steel reo.• Pre- tensioned reo

– Other – Timber, other– Better construction quality &

tolerances– Over driven piles = cracks etc.

Teacher Development ProgramBringing schools and engineering together

Concrete Property:Plastic property• Slump / flow• Passing ability / cohesion

Hardened property• Compressive strength• Drying Shrinkage• Durability

Teacher Development ProgramBringing schools and engineering together

History / Technological change:

Testing and understanding of stone property- Basic

Understand limits in tensile capacity of materials so design uses high comp. strength of mat.

Teacher Development ProgramBringing schools and engineering together

Testing/understanding- conventional steel reinforcing only span so far. Pre-tensioning/Post-tensioning- can significantly increase spans

C

C

T

TC C

Teacher Development ProgramBringing schools and engineering together

Pre-tensioned Concrete • Cables tensioned• Concrete cast onto cables and sticks. • At transfer cables cut and concrete placed in

compression

Teacher Development ProgramBringing schools and engineering together

Post-tensioned Concrete• Cables in ducts not tensioned• Concrete cast onto ducts• Cables stressed and compression provided by barrel /wedge• Ducts grouted to protect cables long-term• Concrete placed in compression some time after casting.

Teacher Development ProgramBringing schools and engineering together

Material property:

Teacher Development ProgramBringing schools and engineering together

• Communications

Michael Van KoeverdenDavid Sparkes

Teacher Development ProgramBringing schools and engineering together

Communications • All communications must be: Clear, Factual & Concise• Verbal/oral – clear instructions (recorded somewhere)• Written – reports- do not embellish or make claims..• Implied- professional service – duty of care to public.• As professional you can be sued for any of above.• PI insurance premiums are based on above depending

on the insurers view of your perceived risk to others.

Teacher Development ProgramBringing schools and engineering together

Communications • Expert Witness work- will be cross-examined in court

to explain your opinion expressed by you.• Need to confirm on what your opinion was based• Must act on most recent knowledge at time of your

report writing. • But still have a duty of care to public.

Communication in Design

Teacher Development ProgramBringing schools and engineering together

• Exam Q and A

Teacher Development ProgramBringing schools and engineering together

Post tensioned- cables not stressed and concrete already hardened.

Teacher Development ProgramBringing schools and engineering together

Teacher Development ProgramBringing schools and engineering together

• Absorb some impact energy• Stops penetration of objects• Improves air bag performance

by staying in surrounds• Can incorporate UV protection Silica

Answer = BMake the section deeper and move the extreme fibre away from the neutral axis.