Construction Technology Flashcards
What types of foundations have you used on one of your schemes
“Strip - concrete strip footing
Vibro - hollow auger, stone pumped in, friction pile
Driven - driven concrete, end bearing, to suitable strata”
What are some types of piles
“Vibro - hollow auger, stone pumped in, friction pile
Driven - driven concrete, end bearing, to suitable strata”
What is RHS & SHS
"RHS = Rectangular Hollow Section SHS = Square Hollow Section"
What are the advantages & disadvantages of steel frame
"Advantages High strength to weight ratio (Lighter) Quick to assemble on site Long spans can be achieved Doesn't impose high load on founds Produced in factory Recyclable
Disadvantages Only produced in geometric shapes difficult to transport May corrode Need fore protection"
What are the advantages & disadvantages of Concrete Frame
"Advantages Good hear and sound insulation In situ or pre cast complex shapes can be achieved potential longer life than steel Potential for passive heating and cooling Doesn't need fire protecting
Disadvantages
Heavy
Slower than steel
Need reinforcement to increase tensile strength”
What are temporary works
Temporary works do not normally appear on construction drawings but demonstrate methods that might be appropriate and resources necessary to ensure safe construction i.e. propping.
What have been temporary works used on one of your schemes
Haul road, formwork, Piling mat, Scaffolding
What are the Advantages and disadvantages of timber frame
“Advantages
Shorter construction period
Lightweight construction
Better quality due to off site construction
Better thermal performance than masonry
Sustainable if grown from sustainable forests
Disadvantages Potential for upfront cost Initial cost is higher Fire risk Acoustic performance worse than masonry Condensation Rot and infestation"
What impact can timber frame and traditional have on cost and programme
Timber can be quicker to start on site and you can achieve efficiencies on site. While it is more expensive to purchase and install it can produce savings on programme
What are NHBC, Premier and LABC
“It is a building warranty that provides a structural warranty to a building. (generally around 10-12 years)
they inspect works to ensure compliance with building legislation and best practice”
what is the benefit of NHBC/Premier/ LABC
“Provides the client with a comfort that the building is instructed correctly
Provides the client/ onward purchaser with a warranty for the building for 12 years”
What role does planning play in development
“It provides a systematic approach to development both long and short term
It does this through national planning policy which is then developed through local and neighbourhood plans”
How do ground conditions affect the foundation selection
The selection of foundations is based on the existing conditions as if the bearing strata isn’t sufficient then the wrong foundation selection would result in issues with the building such as differential settlement subsidence etc
What is a vibro pile
auger is fed into the ground through vibration as It is removed the concrete or stone is pumped into the ground to stabilise weak soils
What is a pre cast concrete pile
Reinforced concrete piles case off site and hammered into the ground
What is made ground
“It is areas of soil that have been re worked or subject to fill.
It can be a combination of materials from demo, reworking and importing”
What would advise the client on the cost of foundations
“Strip founds with concrete ground floor - £210/m2
Mini piles ground beam & ground floor - £320/m2
300mm dia piles pile cap ground beam slab - £500/m2
600mm dia piles pile cap ground beam slab - £800/m2
750mm dia piles pile cap ground beam slab - £1,000/m2”
What are you standard assumptions within an estimate
“Procurement route
OH&P
Prelims
Design fees
design allowance
TPI - BCIS
”
What is covered in a site investigation
“The existing conditions of the site
Former use
Site history
Current site conditions
Existing buildings
Contamination
details of bore holes/ site investigation”
What other surveys would you expect to be carried out prior to start on site for a scheme
"TOPO SI Arboricultural - Trees Ecological - Wildlife Air quality assessment - Potential requirement to offset the CO2 the development will create Acoustic report - will acoustic treatments be required Floor risk assessment Asbestos survey Utility study"
What is a CFA pile
“Continuous Flight Auger
Auger screwed into ground
As it is withdrawn concrete is pumped into the void that is left
Reinforcement is then placed in the bore “
What is thermal massing
A materials ability to absorb and store heat along with the ability to release it
What is a warm roof
Where the insulation is laid within the ceiling joists of a pitched roof. Provides insulated roof. Better thermal performance
What is a cold roof
Where the insulation is within the ceiling and the roof structure
You mention CFA files can you name another couple
“Sheet - Used for earth retention
Driven - driven in with auger
Bored - bore hole made filled with concrete & reinforcement
Insitu pre cast - On site concrete foundation
End bearing - Transfers the load through the pile
Friction - Transfers the load through the adjacent soils #”
You mentioned about undertaking a feasibility estimate for concrete and steel for a client, other than the price difference of the two framing systems, name two other elements that would impact the cost analysis of these two systems.
“Prelims - due to speed
Foundations - Concrete is heavier”
You mention steel vs concrete the Adv & Dis
“Steel
Advantages
- High strength to weight ratio
- Quick to assemble on site
- Long spans (and high heights) can be achieved
- Doesn’t imposed high loads on foundations
- Produced in controlled factory environmental
- Recycle
Disadvantages
- Can only produce simple geometric shapes
- May pose transport difficulties due to large spans
- Parts may need to be replaced over time due to corrosion
- Requires fire protection
Concrete
Advantages
- Good heat and sound insulation qualities
- Can be in-situ or precast (flexible)
- Complex shapes can be achieved in comparison to steel
- Potentially longer life than steel
- Potential for passive heating and cooling
- Doesn’t require fire protection
Disadvantages
- High heights not generally achievable due to heavy weight on foundations
- Slower programme than steel
- Needs reinforcement to increase its tensile strength (as concrete is high in compressive strength and weak in tensile strength) “
What is the difference between a stick system and a unitised system of curtain wall construction?
”- Unitised
o Pre-fabricated in modules off-site and delivered in panels. Unitised systems are better able to exploit the benefits of factory condition manufacturing and quality control and require lower installation time on site.
- Stick
o Installed piece by piece on site, with the glazing inserted into the frame from the inside or the outside depending on access conditions.”
what are the different types of ventilation?
”- Natural ventilation: windows doors
- Mechanical ventilation; Ducts
- Mixed mode ventilation; uses a combo of natural ventilation and mechanical ventilation “
Why would you undertake a soil investigation report
Contamination
Ground water
Bearing strata
What categories of fit out are their
Cat A - the basic finishing of an interior space, installation of a building’s mechanical and electrical services. A Cat A project will also include finished internal walls, reception areas and lift lobbies – but that’s it
Cat B - follows on from a Cat A fit out to provide a space that your company can simply move into and start working, partitions meeting rooms finishes etc
Main ingredient of concrete
Cement
Aggregate
Water
What is a UPS
Uninterruptible Power Supply - provides backup power when your regular power source fails or voltage drops to an unacceptable level
Used for life safety
3 types of floor construction in a building
beam and block, pre cast concrete floors, solid floor
What are section agreements
Legal a local authority and developer
S.278 - Permanent alterations to existing roads/footpaths
S.38 - Construction of new road for adoption
S.104 - sewer construction for adoption
S.50 - Road closure
S.185 - Sewer diversion
S.102 - Adoption of existing sewer
What is the difference between secant and contiguous piles
Secant piles - have male and female piles which form an uninterrupted wallcab retain loose and wet soils
Contiguous piles - have small gaps in-between which can be grouted if required used for basement construction
