Construction Technology (Level 3) Flashcards
What is substructure?
All elements of work that are undertaken below the damp proof course that provides the basis for the superstructure to be constructed upon.
What is the external envelope?
- The materials and components that form the external shell or enclosure of a building
- These may be load or non-load bearing.
What are the Building Regulations?
- Statutory instruments that set out the minimum performance standards for the design and construction
of buildings. - Supported by the Approved Documents and other codes of practice.
What are the approved documents?
(A-T)
A. Structure.
B. Fire safety.
C. Site preparation and damp proofing.
D. Toxic substances.
E. Sound proofing.
F. Ventilation.
G. Hygiene.
H. Drainage and waste disposal.
I. Not in use.
J. Heating appliances.
K. Protection from falling, collision and impact.
L. Conservation of fuel and power.
M. Disabled access and facilities.
N. Glazing.
O. Overheating.
P. Electrical safety.
Q. Security
R. High Speed Electronic Comms Network
S. Electric Vehicle Charging
T. Toilets
What are British Standards?
- Publications issued by the British Standards Institution prefixed BS.
- They give recommended minimum standards for materials, components, design and construction practices.
What are international standards?
- Publications issued by the International Organisation for Standardisation – prefixed ISO.
- They are compatible with and complement the British Standards.
What is superstructure?
- All internal and external works items above the damp proof course.
- This is made up of:
- External walls.
- Stairs.
- Roof.
- Structural walls.
- Suspended ceilings.
- Raised floors.
What are the typical components of site investigations?
- Their objective is to collect and record data to help with the design and construction process. This should include matters in relation to the site that may impact the development for example:
- Boundary hedges & fencing.
- Existing trees.
- Size, depth and location of services including gas, telephone, electricity, water & drains.
- Existing buildings.
- Ground water conditions.
- Soil investigations.
- Trial pit information.
What is the purpose of soil investigations?
- Their purpose is to determine the suitability of the site for the proposed works and determine adequate and economic foundation design.
- The investigation should determine the potential difficulties associated with the ground conditions and assist with identifying a suitable foundation solution.
What are the main site considerations?
- Access considerations.
- Storage considerations.
- Accommodation.
- Temporary services.
- Plant.
- Fencing & hoarding.
- Health & Safety risks.
What is a retained façade?
- The facade of the building is retained whilst everything behind the front wall is demolished.
- Allowances needs to be made for a temporary support structure and also cleaning & restoration works to the retained façade.
- Retained facades are often required as a result of listed building requirements.
What are temporary works?
- Temporary works do not normally appear on construction drawings but may be required depending on the construction methodology being used.
- Temporary works may also be required as a result of health and safety requirements to ensure a safe method of construction for example temporary propping.
What is a tower crane and what are some considerations during its erection and operation?
- A tower crane is a tall crane used for lifting objects into high places.
- The boom allows a longer reach with 360° access.
- A longer boom reduces the payload capability.
- You would usually use a smaller crane to erect a tower crane.
- Weather conditions could prevent it from working, in particular high, strong winds.
What is a scaffold?
- Scaffold is a temporary working platform erected around the perimeter of a building or structure to provide a safe working place at a convenient height.
- Scaffold is usually required for work 1.5m above ground level.
What is shoring?
- Shoring is a form of temporary support given to existing buildings.
- Its purpose is to provide a precaution against damage or injury due to collapse of the structure.
What are the main components of concrete?
- Cement
- Aggregate (natural rock, crushed stone, gravel)
- Water
What is a borehole?
- A borehole can be used for soil investigation or for geothermal heating solutions.
- Boreholes are the most suitable method of soil investigation when foundations are over 3m deep.
- Geothermal boreholes are permanent boreholes that use the Earth’s natural heat to raise the temperature of circulated water.
- This is a closed system and can be used to heat the building above which is adopted as a sustainable technology.
What are piles?
- A series of columns constructed or inserted into the ground to transmit the load of a structure to a lower level of subsoil.
- They are used where no suitable foundations conditions are present near ground level or if there is a high water table.
What are the different types of piles?
- Sheet piles
- Secant piles
- Bored piles
- Pre-cast piles
What are sheet piles?
- A deep trench is excavated and concrete is poured in situ.
- The piles can be used to form basement walls or act as retaining walls.
What are secant piles?
- Interlocking piles (male and female, often different diameters and hardness) are bored to provide a combination of foundations and basement walls.
- They support in providing a waterproof structure and are often seen when a top down construction method is used.
What are bored piles?
An auger is used to excavate the soil and then concrete is poured in once complete.
What are pre-cast piles?
Piles are and hammered into the ground. This is not often favoured due to the high noise levels associated with installation and the lack of flexibility in terms of depth required.
What is a raft foundation?
- Raft foundations spread the load of the superstructure over a large base and reduce the load per m2 of the area.
- Raft foundation solutions are useful in low bearing capacity soils.
- They can be a solid raft slab or beam and slab raft such as a ground beam system and suspended PC concrete ground floor.
Under what conditions would you expect a raft foundation to be used for a substructure?
- A raft can be used for lightly loaded buildings on sites with poor soils.
- Heavy loads to the raft have the potential to cause the raft to move sideways as a result of raft foundations not being very deep.
What is a strip foundation?
- Strip foundations are formed by creating a shallow continuous excavation to support the perimeter and internal walls.
- They are also referred to as strip footings and are suitable for most subsoils and a light structural design.
What are pad foundations?
- Pad foundations provide a base for reinforced concrete or steel columns.
- They are usually formed by making an isolated excavation in the shape of a square or rectangle.
- They often have reinforcement mesh as part of the construction and spread the load to a layer of bearing soil or rock below.
What are retaining walls?
- They act as an earth retaining structure for the whole or part of their heights.
- They are used to support and retain soils laterally so that it can be retained at different levels on the two sides.