Philip Zhu 1
ENGG 1800 notes
40% of total, 6cp subject
90 min exam consists of two sections o Chem and civil
o Two questions in each section, do ONE of them
Civil consisted of:
o Structure building o Paddlepop stick bridge
o Bridge lecture and Maxwell truss diagram o Stability in wind assignment
o Construction networks assignment
o Making a cardboard box from engineering drawing
Chemical consisted of:
o Tutorial exercises on mass and energy balance (questions on charge and energy to come from different masses/volumes of hydrogen
o Experimental production of hydrogen using fuel cell, and then production of energy using that hydrogen just produced
o Control in production of hydrogen gas and the production of energy from it, run the car for a certain time
o Written article Civil
A truss bridge is defined by having its trusses arranged in triangles o As opposed to suspension and cable stayed bridges
Philip Zhu 2
Odd notes
o Exhaust from Sydney harbour tunnel is vented from top of north eastern pylon of harbour bridge
o Building the harbour tunnel
1. Made of 8 huge pre-cast concrete sections
2. Seal the ends of those sections and float them out of the dry dock
3. Fill water tanks in sections to make neutrally buoyant/just barely sinking
4. Floatation tanks on top, at water level hold the tunnel section
Tunnel section is suspended
5. Move section in to position
6. Add more concrete in the section to weigh it down
7. Remove water tanks
8. Join the sections
Structure building
o Cable stayed bridge, suspension bridge, truss bridge and portal frame building o Cable stayed bridge
Cables transfer deck load to one or more towers
Harp and fan designs
Fan design where all cables terminate at the same place on the tower/pylon
Harp design where height of attachment to tower is proportional to distance from tower of decking mounting
o Further from tower is attached higher on tower o Eg, Milau Viaduct
Fan design is structurally superior but harp allows more cables and more space between cables at termination point, therefore more practical
Structural principle
Cables transfer load on bridge deck to the pylons, cables in tension, tower in compression
Construction sequence
Pylon built first, then deck built evenly outwards from centre o Truss bridge
Load bearing consists of 2 trusses with elements connecting at nodes.
Different elements are in compression and tension
One of the oldest types of bridge for spanning significant distance
Many types of truss bridge, eg, Parker Truss (Pratt truss is flat across top)
Structural principle
Parker truss has top chords in compression with rest in tension
Truss bridges declined in popularity since 1950s due to advances in reinforced concrete and as cost of labour increased
