Document Questions Flashcards
Can you tell me how you’ve advised a client on the foundation selection?
Soil type
Cost/Time
Type of structure
Buildaibility (access, proximity, site conditions)
What is piling?
Where RC concrete is in the ground to take the load of the structure
Typically reinforced
Used on large buildings with heavy load and subsoil is not able to take the load
What are the advantages of CFA piling?
Low levels of noise and vibration
High load bearing
Suitable for a wide range of ground conditions
What is the difference between displacement and replacement piling?
Displacement driven into the ground without excavation
Replacement is CFA piling
What is a typical ground floor slab build up?
Finish
Screed
DPM
Insulation
Slab
Sand/Blinding
DPM below slab`
What is included within one of your projects substructure?
On Tolworth Phase 1 we had a piled substructure which included:
- 600 dia piles
- Pile Caps
- 300mm RC ground bearing slab
When would you advise to use a piled foundation?
High rise building
High load bearing
Subsoil cannot hold weight of structure
Explain activities involved when piling?
Measure in line with Section 1 of NRM1
Forming pile mat Mobilisation/moving of pile rig Pouring insitu RC piles Cutting top of piles Pile Caps Pile testing Pile casings if applicable
Why would you use rotary bored piles instead of CFA?
Rotary bored piles Larger diameter than CFA Support greater loads Penetrate ground too hard to CFA Pile can be reinforced entire length because the rotary bored technique enables the entire cage to be added as it can be dropped prior to concrete pour
What was the cost difference per pile for RTB and CFA?
Dependant on dimensions and rebar density
RTB £25k/pile (>900 dia, 60m deep) CFA £4k/pile (700 dia, 30m deep), CFA £2.5k/pile (600mm dia, upto 26m long)
How do piles work in regards to transferring loads?
End bearing will transfer load to strata
Friction will rely on the strength of the soil to be able to create friction between piles to prevent movement and transfer load
Why would you use CFA piles instead of Bored?
Better soil conditions
Cost
Quicker than Bored (concrete done as excavating)
How would you measure a Steel Frame?
Measure steel in tonnage
Intumisant paint
Accessories and fixings could be included
Plates and holding down bolts cast into foundation
Each steel member measured in tonnage
What are the main forms of legislation in the industry?
Construction Act (HGCRA1998) Local Economic and Democracy Act HASAWA CDM Regulations Building Regulations Fire Regulations Party Wall Act Proceeds of Crime Act Anti Bribery Act
What are the CDM Regulations?
The Construction (Design & Management) Regulations (CDM 2015) are the main set of regulations for managing the health, safety and welfare of construction projects.
Pre-construction activities to ensure works are being carried out safely
What are the Building Regulations?
List of approved documents ( A - R) which building work must be complied to :
Part A- Structure
Part B- Fire
Part Q- Security of Dwellings
What are the Fire Regulations?
Regulations that specify to legislation and laws relating to fire as set out in Part B of the Building Regs
What is your role in relation to the CDM Regs?
Due to my input in reviewing drawings and having an influence on design I am aware that I am seen as to having a role as a designer in relation to CDM Regs.
Name different types of planning consent types
Outline
Full
Non material amendments
What do the GLA state regarding units per core?
GLA this should not exceed 8 residential units per core.
How would you build a rate for a frame?
C40/50/60 concrete to: - Ground Bearing Slab - Suspended Slabs - Columns - Beams - Transfer beams/slabs - Beams - Walls Reinforcement (to S.E recommendation)Formwork to soffits Formwork to edges
What is a cold roof and its + & -
Waterproof layer
RC
Void for ventilation
Insulation
Better for heavy plant on roof
Requires void to avoid damp / condensation
Difficult to construct
What is a warm roof and its + & -
Waterproof layer
Insulation
Vapour Control
RC
Typically better for warmth and waterproofing
Not great for greater loads on roof
Why are transfer slabs required?
To help with load bearing- for example on my project there were columns on the GF that were required to be moved and the load from above had to be transferred via a transfer slab into the columns
What are the advantages of using precast concrete frame?
Produced in factory-controlled conditions
Eliminates curing times and formwork
Can be assembled in cold weather and generally by semi-skilled labour
What are the disadvantages of using precast concrete frame?
Less flexible in design terms
Longer lead times
What factors should be considered when choosing between a frame type?
Fire proofing requirements
Acoustic requirements
Time
Site logistics (e.g. delivery of materials to site, on/off site storage, plant restrictions)
Cost
Requirements for thermal mass for a low energy design solution
Repetitiveness
In your documents you have highlighted the advantages/ disadvantages of Steel v Concrete. Could you talk me through some of these?
Steel
Advantages:- Quicker to construct- Recyclable- Strong tensile strength Lighter than concrete
Disadvantages- More volatile pricing - Low compression strength - Low sound/fire resistance - Requires soundproofing
Concrete
Advantages
- High compression strength
- Good noise resistance
- Good fire protection
- Low maitenance
Disadvantages
- Slower to construct
- Need for reinforcement
- High embodied carbon-
- Not as square and flat as steel
Are you aware of any renewable technology techniques?
London 0% Carbon Local labour Photo voltaic panels Blue / Green Roof Presence detectors ASHP GSHP
Difference between steel / concrete with regard to life cycle costing?
Concrete
Cheaper / Easier to repair
More flexible
Steel
Difficult to repair as done in large spans
Expensive