Topic 3 Flashcards
What are vector and scalar quantities? Providde 3 examples for both.
Vector - Has mangitude and direction
Example
- displacement
- acceleration
- velocity
- force
Scalar - only has magnitude
Example
- mass
- area
- volume
- density
- speed
what is reinforced concert and what are its material properties of it?
Concrete can be reinforced by steel rods, bars, or mesh to absorb the tensile and shear stresses put upon. On its own concrete can handle high levels of compressive stress, but in situations where tensile or shear stress is present, in earthquakes, it is weak.
What is pre-tensioning? What does it do?
Is when steel cables are strechted before the concrete is poured. When the cables are still in tension the concrete is poured and cured. once cured the steel is realsed, putting the concrete understand compression stress, causing it to buoy (into an arch), this increases the concrete tensil force. As when in tension, concrete goes back into neutral.
Name some civil-engineering sub-disciplines.
- structural
- construction
- environmental
- costal
- earthquake
- water source
What is a construction engineer do?
Oversees the design and building process of construction projects.
Ensure buildings, projects, and construction teams are safe.
They may also help design infrastructure systems, such as roads, dams, water supply systems and buildings.
What does a structural engineer do?
Addresses the design, construction, and maintenance of public works.
Pays the most attention to infrastructures, such as bridges, tunnels, transportation routes, water treatment facilities and government buildings.
What does an earthquake engineer do?
Make roads and buildings safer in the event of major earthquakes. This includes both improving the design of new buildings and bridges as well as strengthening older units to incorporate the latest advances in seismic and structural engineering.
What does an environmental engineer do?
Assess the impact on air, water, soil, and noise levels in the vicinity of engineering projects, plan and design equipment and processes for the treatment and safe disposal of waste material, and assess what may cause problems for the environment in the long term.
What are some impacts engineered structures and civil engineering have on the environment?
- deforestation
- habitat loss
- pollution
- biodiversity decrease
- interpurtion of water
- use of fossil fuels
what impacts can the environment have on civil structures?
- Erosion
- wildlife (pests)
- natural elements (wind, rain etc.)
- landslides
What are some examples of commonly used materials in civil engineering?
Explain engineering properties, lifecycle, and environmental impacts.
Concrete:
- high compressive strength
- pre-tensioning = + tensile strength
- made from sand, cement, water, and gravel(also made from synthetic materials)
- very environmentally unfriendly (accounts for 5% of global carbon emissions), can be recycled
Wood/timber: Insulative, Thermal conductive, hard, Aesthetic - readily available - Sustainable + renewable - Energy is effective in producing - can be recycled
Glass: transparency, heat resistance, pressure and breakage resistance, and chemical resistance.
- very sustainable
- fully recyclable
- hard, brittle
Mild steel:
- High tensile strength.
- High impact strength.
- Good ductility and weldability.
- A magnetic metal due to its ferrite content.
- Good malleability with cold-forming possibilities.
- Fully recyclable
- steel product has high environmental impacts
Cast iron:
- is hard and tough
- can be recycled without losing its material properties
- mining for the ore cause pollution
Acrylic Polymethyl Methacrylate :
outstanding strength, stiffness, and optical clarity
- not sustainable
- production requires the petrochemical industry (meaning synthetic materials)
- is recyclable
- not biodegradable
Order steel in order from less carbon % to most. Also, provide carbon percentages
Low carbon steel = 0.07% - 0.15% Mild steel = 0.15% - 0.3% Medium steel = 0.3% - 0.6% High carbon steel = 0.6% - 1.25% Ultra high carbon steel = 1.25% - 2.5%
Name the 3 types of bar assemblies
- unstable
- stable
- redundant
What is built-in / planned obsolescence and the issues around sustainability / reliability / ethical / environmental
The policy of planning or designing a product with an artificially limited useful life or a purposely frail design.
Environmental issues:
- increased production
- waste
- pollution
- not recycling
Ethical issues:
perpetuating a “buy new and often buy” mentality and limiting consumer autonomy to keep products longer by hard-wiring a “self-destruct” button in products
Reliability Issues:
What materials were in common use throughout ancient civilizations such as the ancient Romans, Greeks, and Egyptians
stone, lime, thatch, wood, mud, bricks, marble,
