Construction technology and environmental services Flashcards
Different types of pile foundations?
- Bored/replacement
- Driven/displacement
- Secant pile walls
- Contiguous pile walls
What type of foundation would you use in a city centre with low bearing capacity soil?
Bored piles because:
- Require deep penetration to get to soil with adequate bearing capacity
- Bored gives less vibration/noise, so won’t disturb neighbouring structures or tenants (likely in city centre)
When would you use strip foundations?
- Often for masonry facades where strip will follow the line of the structural brick wall
- Good soil in terms of bearing capacity
- Light load
Why would you use pad foundations?
To spread the load of a column over a wide surface area.
Possible if the load isn’t huge and/or the soil bearing capacity is good
When would you use steel for frame construction?
- Where large open spans are required such as cinemas, offices
- Tall buildings as it has better strength to weight ratio
- Quick on-site construction
- Where flexibility is important
When would you use concrete for frame construction?
- Where large open spans are not required e.g. residential
- Flexibility is less important
- High-rise residential blocks where combustibility is a consideration
Pros/cons of concrete?
Pros
- Good thermal insulator
- Good acoustic insulator
- Doesn’t require additional fire protection
- Can be cheaper than steel
- In situ good for cashflow as it’s slow
- Cladding easily connected
- In-situ means late changes possible
- Can deal with complex geometry better than steelwork
Cons
- Good concrete subcontractor important
- Bad for embodied carbon
- Heavy
Pros/cons of steel?
Pros
- Good strength to weight, lighter than concrete
- Tension strength means good for long spans
- Quality assurance, prefabricated
- Quick to assemble
- Recyclable
- Not combustible
Cons
- Bad for embodied carbon
- Requires fire protection, will fail under fire otherwise
- Can corrode
- Requires experienced builders
- May need parts replacing
- Price fluctuates
What are the pros/cons of timber-framed buildings?
Pros
- Sustainable (FSC)
- Low embodied carbon
- Good for carbon sequestering
Cons
- Can’t do high buildings, column requirements become too big
- Requires acoustic and fire protection
- Expensive
What are the benefits of pre-fabrication?
Pros
- Economies of scale
- Sustainable / less waste
- Consistent quality
- Safety risk reduced as constructing in factory controlled environment
- Fast installation time on site
Cons
- May not always be cheaper
- Finished product sometimes less desirable in the market
What are retaining walls?
They act as an earth retaining structure for the whole or part of their height
What are the Building Regulations?
Statutory instruments that set out the minimum performance standards for the design and construction of buildings.
Supported by approved documents A - R & regulation 7.
Name the approved documents of Building Regulations
A - Structure
B - Fire safety
C - Site preparation and resistance to contaminants and moisture
D - Toxic substances
E - Resistance to the passage of sound
F - Ventilation
G - Sanitation, hot water safety and water efficiency
H - Drainage and waste disposal
J - Combustion applications and fuel storage systems
K - Protection from falling, collision and impact
L - Conservation of fuel and power
M - Access to and use of building
P - Electrical safety
Q - Security
R - High speed electronic communications networks
Regulation 7 - Materials and workmanship
What is the substructure?
All structure below the superstructure i.e. all structure below the ground including the ground floor bed
What is the superstructure?
All internal and external structure above the substructure
What are foundations?
Foundations provide support for structures, transferring their load to layers of rock and soil that have sufficient bearing capacity
What are the main components of concrete?
Water, aggregate (rocks, sand etc), cement
How are bored piles installed?
Continuous Flight Auger for bored piles
Drills hole into ground, pulling up earth as concrete is poured down at the same time through hollow centre of auger.
Steel then forced into wet concrete
What forms of modern methods of construction are you aware of
- Cross laminated timber (used for making giant span panels)
- Glued laminated timber (Glulam) (used for making giant span beams)
- Modular construction
- 3D Printing
What is buildability?
Buildability is a pre-construction exercise that assesses designs from the perspective of those that will manufacture, install components and carry out the construction works. This is in relation to:
- Achieving the desired final quality
- De-risking perceived problems
- Achieving optimum value for money
- Meeting the programme requirements
What is fire compartmentalisation?
The spread of fire can be restricted by sub-dividing buildings into a number of discrete compartments. These fire compartments are separated from one another by compartment walls and compartment floors made of a fire-resisting construction which hinders the spread of fire
What are recent changes to Building Regulations?
- Fire safety - no combustible material in buildings above 18m
- Sprinklers in buildings above 11m
- Responsible person (property manager) to manage the fire safety in blocks
What is a party wall?
- A party wall is the shared wall, usually between a terrace or semi-detached house, and divides the homes of two separate owners
- The Party Wall Act 1966 provides a framework for preventing and resolving disputes in relation to party walls, boundary walls and excavations near neighbouring buildings
What is the rights of light?
Right to receive sufficient light through an opening (such as a window), allowing ‘ordinary’ comfortable use and enjoyment of a dwelling, or ‘ordinary’ beneficial use and occupation of other buildings
