Construction Technology Flashcards
(113 cards)
1
Q
What RIBA stage is on-site construction?
A
RIBA Stage 5 – Manufacturing and Construction
2
Q
What is buildability?
A
Buildability can be defined as the extent to which the design of a building facilitates the ease of construction
3
Q
What are the benefits of off-site construction over in-situ construction?
A
Safety – Hazards such as falls from height are more likely to occur on site than in a factory.
Efficiency and quality – Construction takes place in a controlled environment.
Sustainability – Reduction in waste produced.
Speed – work in the factory can be scheduled to begin at the same time as other activities on site, resulting in a shorter build programme.
4
Q
What is the difference between building works and civil engineer works?
A
Building works: all types of buildings such as houses, offices, shops, hotels.
Civil engineering works: drainage schemes, highways, culverts, bridges.
5
Q
What is the substructure of a building?
A
Substructure is the lower portion of the building (in the ground) which supports the superstructure. It transmits the loads of the building to the ground.
6
Q
What are some of the techniques available for ground improvement?
A
Vibro compaction, Soil mixing, Dynamic compaction.
6
Q
What is ground heave?
A
Ground heave is usually associated with clay soil, which swells when wet, causing the upward movement of the ground. As the soil generally cannot expand downwards or sideways, the result is that the exposed upper surface of the soil rises.
7
Q
What are the different forms of excavation?
A
Site clearance, Stripping topsoil, Cut and Fill, Excavation for foundations.
8
Q
What are the key factors the contractor should consider when excavating?
A
Nature of the soil and the moisture of the ground, method of excavation, proximity of existing buildings, depth of excavation, underground services and drainage.
9
Q
Can you explain some of the techniques for waterproofing a basement?
A
Tanking – materials such as asphalt and bitumen are applied internally or externally to provide a continuous membrane to the base slab and walls.
Drained cavity – This method accepts that a small amount of water seepage will occur. Cavity walls are formed, and the water seepage is collected in the cavity and drained or pumped away.
10
Q
What are SUDS?
A
Sustainable Urban Drainage System. They are designed to manage stormwater locally and mimic natural drainage to encourage its infiltration. Can help reduce the reliance on existing drainage infrastructure.
11
Q
Give some examples of a SUDS?
A
Green roofs, Detention Basin, Wetlands.
12
Q
Can you detail a typical road build-up?
A
Compacted and rolled type-1 subbase (100-250mm)
Base course (70-150mm)
Binder course (50-100mm)
Wearing/surface course (20-40mm)
13
Q
What are the two main types of roads/pavements?
A
Rigid and Flexible
14
Q
What are the characteristics of flexible pavements?
A
Bitumen and asphalt aggregates are typically used. The structure of the pavements is designed to bend and deflect according to external factors like traffic loads and weather.
15
Q
What are the advantages of flexible pavements?
A
Can be applied during the pre-construction phase, repairs are easy and can be opened and patched, materials are inexpensive, short curation time means short traffic and business disruptions.
16
Q
What are the disadvantages of flexible road/pavements?
A
Shorter lifespan than rigid pavements, frequent maintenance required which drives up cost.
17
Q
What are the characteristics of rigid pavements?
A
Typically made out of cement concrete with a base and sub base. Unlike flexible pavements, rigid pavements do not bend under pressure. Top layer of concrete absorbs most of the pressure and weight from traffic.
18
Q
What are the advantages of rigid pavements?
A
Longer lifespan, maintenance costs are low, allows for future asphalt resurfacing, allows for wider load distribution with fewer base and sub base requirements, can be installed on low and high quality soils
19
Q
What are the disadvantages of rigid pavements?
A
Initial installation fee is expensive, costs of repairs is expensive. Low and very rough riding quality.
20
Q
What is the purpose of a foundation?
A
Foundations provide support for structures, transferring their load to the ground to avoid excessive settlement. The foundations should bear the loads of the superstructure.
21
Q
What are the typical considerations when selecting the type and size of foundations?
A
The total load of the building, load bearing capacity of the ground, type of structure, cost.
22
Q
What is a raft foundation?
A
A raft foundation is a continuous slab that extends over the entire footprint of the building. The raft spreads the load of the building over a larger area than other foundations, reducing the stress acting on the ground below.
23
Q
What are the different foundation types?
A
Pad, Strip, Pile, Raft
24
What are pad foundations?
Pad foundations are typically used to support individual or multiple columns, spreading the load to the ground below. They are usually square or rectangular and can be reinforced.
25
What are strip foundations?
Strip foundations are a strip of linear structure that serves to spread the weight across the total area of the ground and is typically used to support masonry.
26
What are pile foundations?
Pile foundations are columns that extend deep into the ground. Where the bearing capacity of soil is poor or imposed loads are very heavy, pile foundations may be required.
27
What are the two main types of piles?
End bearing piles. Friction piles.
28
What are the two main construction methods?
Bored piles. Driven piles.
29
In what scenarios might a piled foundation be the best solution for the project?
Where the structure is heavy and the underlying soil is weak. In areas where settlement issues are common. Where the water table is high. Where the load distribution of the structure is not uniform.
30
Can you explain how end bearing and friction piles transfer the load of the building?
End bearing piles – The bottom of the pile rests on a layer of strong soil or rock, the load of the building is transferred through the pile onto the strong layer.
Friction piles – Friction piles work on a different principle, friction piles develop most of the pile-bearing capacity by shear stresses along the side of the pile. In other words, the surface of the pile looks to transfer the forces to the soil.
31
What are the differences between bored and driven piles?
A driven pile is formed off site under factory-controlled conditions and a bored pile is cast on site.
32
What are the key advantages and disadvantages of driven piles?
Pile can be precast to the required specifications. Piles can be of any size, length, and shape and can be made in advance. A pile driven into granular soil compacts the adjacent soil mass and therefore can result in the bearing capacity of the pile increasing as a result. Fast, neat, and clean installation.
33
What are the disadvantages of driven piles?
Requires heavy equipment for handling and delivery. Increased noise and vibrations generated by driving the piles. It can be costly if the piles are too short.
34
What are the key advantages of bored piles?
Any size or shape of pile can be formed on site. No risk of damage during delivery and handling. Reduced vibrations and noise.
35
What are the key disadvantages of bored piles?
Significant spoils are generated that need to be handled. Reliance and coordination on multiple trades. Unlike driven piles, bored piles do not improve the bearing capacity of the ground.
36
What are secant pile walls?
A wall formed by installing interlocking piles which create a solid barrier free of gaps. Typically used for a retaining wall.
37
What is underpinning?
Underpinning is a method for repairing and strengthening existing foundations.
38
Why might underpinning be required?
Stabilising foundations undergoing settlement, foundations moved due to landslide. To increase the load capacity of existing foundations. To accommodate a new adjoining building, new basement etc.
39
What is the superstructure of a building?
The structural components of a building which are constructed above the damp-proof course. The basic components include a building’s superstructure are columns, beams, slabs, walls, roof, floors.
40
What is the envelope of a building?
A building envelope is the boundary between the interior and exterior of a building.
41
What are key considerations when designing external walls?
Weather protection, fire resistance, acoustic and thermal performance, structural performance, appearance/aesthetic.
42
Can you briefly explain what a retained façade is?
The façade of the building is preserved while the rest of the structure is re-modelled, or a new structure is built behind it. It is often used when restoring listed buildings.
43
What are standard brick dimensions in the UK?
215mm x 102.5mm x 65mm
44
How many UK standard bricks are required per m2.
60 bricks per m2.
45
How many UK standard size blocks are required per m2?
10 blocks per m2.
46
What is the average price per m3 of concrete?
£100
47
What are weep holes?
Small openings in the outer skin of masonry construction. They provide ventilation for the cavity and allow moisture to drain away.
48
Can you name two different types of brick bond?
English bond – Alternating courses of headers and stretchers
Stretcher bond – The most common brickwork method .The vertical joints are staggered each time by half a brick.
49
What is a curtain wall system?
Typically, curtain wall systems comprise of a lightweight aluminium frame onto which glazed infill panels can be fixed.
50
What are movement joints and why are they used?
A movement joint is designed to safely absorb the expansion and contraction of construction materials. Movement joints can also allow the movement associated with ground settlement.
51
What are the main components of concrete?
Cement, aggregate/sand, water.
52
What is the difference between live loads and dead loads?
Dead loads are static forces that are relatively constant for an extended period of time; usually the weight of the materials plus non-structural elements such as partitions, immovable fixtures, kitchens etc.
Live loads refer to the dynamic forces from occupancy and intended use. These loads include the weight of people, furniture, appliances, moveable equipment etc.
53
What are retaining walls?
A retaining wall holds back the soil behind it. The typical purpose is to resist the lateral forces of soil where there is a change in ground elevation.
54
What is pre-tensioned concrete?
The tendons or cables are stretched (put into tension) across the concrete formwork before the concrete is placed into a mould. After the concrete is hardened and a suitable strength has developed, the tendons are released. The tendons attempt to shorten and transfer the stored energy to the concrete. A compressive force is therefore induced in the concrete.
55
What is the application of pre-tensioned concrete?
Production is limited to factories and is for pre-cast work. Small sections are to be constructed only. Loss of pre-stressing (about 18%). Preferred when the structural element is small and easy to transport. Cheaper because the cost of sheathing isn’t involved.
56
What is post-tensioned concrete?
The concrete is cast around the tubes or ducts which will contain the reinforcing tendon. Once a suitable concrete strength has developed, the tendons are threaded through the ducts and stretched (put into tension) using hydraulic jacks.
57
What is the application of post-tensioned concrete?
Can be carried out on site as well as in factories. The size is not restricted and can be applied to long-span bridges. Loss of pre-stressing (about 15%). Preferred when the structural element is heavy. More expensive as sheathing is involved.
58
What is the benefit of pre and post tensioned concrete?
Concrete is subjected to compression to reduce or nullify the effects of dead and live loads.
59
Can you explain what glulam beam is?
The term glulam is an abbreviated term for glue-laminated timber. It is made with multiple layers of solid wood bonded together with high-strength adhesive to form a single structural unit.
60
Can you explain what reinforced concrete is?
Reinforced concrete is a combination of concrete with reinforcements (usually steel bars). This combination is made to use the compressive strength of concrete and the tensile strength of steel at the same time, hence, they work together to resist many types of loading.
61
What are the key advantages of timber frames?
Construction on-site can be faster. The structure is relatively lightweight. Timber can be aesthetically pleasing. More sustainable (assuming the timber is harvested responsibly).
62
What are the key disadvantages of timber frames?
Skilled workmanship is required to achieve a high quality finish. Potential for wet rot, dry rot, woodworm. Fire protection may be required.
63
What are the key advantages of steel frames?
Faster to erect than concrete frames, Recyclable, high strength to weight ratio, beams can span over long distances.
64
What are the key disadvantages of steel frames?
Typically, steel frames have a lower load bearing capacity compared to concrete frames. Fire protection may be required. The price of steel can fluctuate. Steel frames do not have the same acoustic and thermal properties as concrete frames.
65
What are the key advantages of concrete frames?
Fire protection is inherent in the structure. Cladding and other finishes can be fixed directly to the frame. Provides good sound and heat insulation. High compressive strength.
66
What are the key disadvantages of concrete frames?
Require formwork. Slower to construct on site. Requires a bulky structure. Concrete does not span as well as steel. Long curing time – maximum strength typically achieved after 28 days.
67
With reference to concrete, what is formwork?
Formwork is the structure, usually temporary, used to contain poured concrete and mould it to the required dimensions.
68
What key factors should be considered when selecting the type of structural frame?
Programme requirements, fire protection, acoustic and thermal properties, market conditions and supply costs, site logistics and site constraints, end user requirements (column free space), sustainability objectives such as BREEAM.
69
What is slipform construction?
Slipform construction involves pouring concrete into the top of a continuously moving formwork. As the concrete is poured, the formwork is raised vertically at a speed that allow concrete to harden before it is exposed at the bottom. Typically used to construct stair cores, lift shafts etc.
70
What is jump forming?
Jump forming works on a similar principle to slipform. The structure is cast in a series of vertical sections called lifts. After the concrete has gained sufficient strength, the formwork is moved back and then jumped to the next level above.
71
Why do we install generators in addition to regular grid power?
Generators, usually powered by diesel engines, typically act as a backup power supply should the primary power supply fail.
72
What is natural ventilation?
Natural ventilation is a method of supplying fresh air to a building or room by means of passive forces, such as wind speed. This is achieved without the use of mechanical systems, therefore reduced carbon emissions are a key benefit.
73
What is mechanical ventilation?
Mechanical ventilation is the intentional, fan-driven flow of outdoor air into a building. Mechanical ventilation systems may include supply fans (pushing outdoor air into a building), exhaust fans (drawing air out of a building), or both.
74
What is an air source heat pump and how does it work?
An air source heat pump takes heat from the air and boosts it to a higher temperature using a compressor, it then transfers heat to the heating system. Their function resembles the working of a fridge or air-conditioner, but in reverse.
75
What is the purpose of a parapet?
A parapet is an extension to the external building shell above roof level. It can be used as edge protection to enable maintenance to take place and can also mask unsightly roof plant from ground level.
76
What key factors should be considered when designing internal partitions?
Fire rating and acoustic requirements, Thermal properties, requirement for doors and internal windows, strength and structural requirements, height & cost.
77
What is a CAT A fit out?
CAT A fit out typically provides a basic level of finish, this may include raised floors, suspended ceiling and partitions, along with basic mechanical and electrical services. Often bare-bones finish and a blank canvas for interior designers.
78
What is a CAT B fit out?
CAT B fit out provides a space that is ready to move in. Includes floor finishes, specialist lighting and facilities, kitchen area, furniture.
79
What are temporary works?
Temporary works are the parts of a construction project which are needed to enable the permanent works to be built.
80
Provide examples of temporary works?
Scaffolding, Formwork, Excavation support.
81
What is a culvert?
A culvert is a tunnel-like structure that is constructed to allow water to flow under a road, railway line or similar obstruction
82
What surveys might be required for a typical construction project?
Site investigation, Asbestos, Drainage CCTV survey, Ecology survey, flood risk assessments, Archaeological surveys.
83
What are the objectives of a site investigation?
The primary purpose is to establish parameters for foundation and substructure design. The engineer will assess the properties and composition of the soil and rock, as well as potential ground contamination that could affect construction or building safety.
84
What is a CBR test?
California Bearing Ratio. Tests the load bearing capacity of the ground to inform foundation design and construction details for other ground bearing elements.
85
Which types of vegetation can cause issues for a construction project?
Japanese knotweed.
86
Are you aware of a RICS professional standard associated with Japanese knotweed?
Japanese knotweed and residential property – 1st edition, January 2022.
87
What fire safety provisions might you find in a new building?
Maximum occupancy numbers, fire evacuation plan, designated escape routes, fire alarms, fire extinguishers, sprinklers, fire dampers.
88
What is a fire compartment in a building?
Compartmentation is a form of passive fire protection. The idea is to subdivide a structure into fire compartments to limit the spread of fire and smoke.
89
What is intumescent paint?
Intumescent paint is a passive fire protection system. When exposed to extreme temperatures, it rapidly expands to protect the surface that it is applied to. This prevents, minimises, or delays fire damage to the structure.
90
What are automatic fire sprinklers and how are they activated?
Sprinkler heads are usually heat-activated. When the heat of a fire reaches the sprinkler head, a solder link will melt or a liquid-filled glass bulb will shatter to activate the sprinkler, releasing water directly over the source of the heat.
91
Can you detail the different types of fire extinguishers and their typical use?
Water – wood, cardboard, textiles.
Foam – flammable liquids.
Dry powder – flammable liquids and electrical fires.
Carbon dioxide – electrical fires.
Wet chemical – cooking oil fires.
92
What is a mansafe fall arrest system?
Mansafe systems are horizonal or vertical safety lines designed to keep people safe while working from height. The user will wear a safety harness and clip onto the safety line. If a fall should occur, the system is designed to limit the distance and consequence of the fall.
93
What are British regulations?
Regulations to ensure that new buildings, conversions, renovations, and extensions (domestic or commercial) are going to be safe, healthy, and high performing.
94
Can you list the Building Regulations Approved Documents?
Part A – Structure
Part B – Fire Safety
Part C – Site Preparation
Part D – Toxic Substance
Part E – Sound resistance
Part F – Ventilation
Part G – Sanitation, hot water, and water efficiency
Part H – Drainage and waste disposal
Part J – Combustion appliances and fuel storage systems
Part K – Protection from falling, collision, and impact.
Part L – Conservation of fuel and power.
Part M – Access to and use of buildings.
Part O – Overheating.
Part P – Electrical safety.
Part Q – Security in dwellings.
Part R – High speed electronic communications network
Part S – Infrastructure for charging electric vehicles.
Approved Document 7 – Materials and workmanship
95
What was changed in Approved Document Part B following Grenfell?
Sprinklers now required in buildings 11m high from previous 30m.
More than one common staircase to be provided in block of flats with a storey 18m or more in height, and building design provisions to support the use of evacuation lifts in blocks of flats.
Ban of aluminium composite material for cladding.
96
Provide some examples of what is contained within Approved Document Part C?
The document outlines the source-pathway-receptors to contaminants in land.
Outlines the remedial procedures when coming across moisture, contaminated land, gases such as Radon and Methane.
97
Provide some examples of what is contained within Approved Document Part L?
All new homes must produce at least 31% less carbon. New homes U-values in walls needs to be improved from 0.28W/m2 to 0.18 W/m2.
98
Provide some examples of what is contained within Approved Document Part M?
Requirements for wheelchair accessibility for wheelchair use dwellings, such as accessibility to outdoor space and ramps to access property.
99
Who reviews the design and construction phase for compliance with Building Regulations?
The building control officer or approved inspector
100
What are British standards?
Publications issued by the British Standards Institution. They give recommended minimum standards for materials, components, design, and construction.
101
Can you name some materials banned from use in construction?
Asbestos, High alumina cement in structural elements, Urea formaldehyde.
102
What is the Equality Act 2010?
The act legally protects people from discrimination in the workplace and wider society. The equality act replaced previous anti-discrimination laws with a single act to cover all maters such as disability, race, sex, gender, pregnancy, religion, belief.
103
How does the Equality Act affect buildings?
While the accessible design of buildings is regulated by the Building Regulations Part M, the Equality Act requires ‘reasonable adjustments’ to be made when providing access to goods, facilities, services.
104
Can you explain what the Party Wall Act 1996 is?
The Party Wall Act 1996 provides a framework for preventing and resolving disputes in relation to party walls, boundary walls, and excavations near neighbouring buildings. The act is separate from obtaining planning permission.
105
Can you briefing explain what O&M manuals are?
Operation & Maintenace manuals . Upon completion of the build phase, O&M manuals are issued to the client/building owner (produced by the contractor). Information relating to how the building has been constructed, should be maintained, cleaned, and decommissioned. Includes as built drawings and specifications.
106
Define Value?
Value relates to the ratio between the benefit derived from a course of action and the cost or effort required to achieve it.
107
Define Value for Money?
It is a way of evaluating whether the benefits obtained from a project or investment are worth the resources expended?
108
What is the benefit cost ratio formula?
It is the net benefits divided by the net costs.
109
What are the benefits of ETFE (Ethylene tetrafluoroethylene)?
Safety – Extremely fire-safe. Does not promote the spread of flames and is considered a self-extinguishing material.
Maintenance – Since it is not affected by UV light, atmospheric pollution, and other forms of environmental weathering, ETFE has a good life expectancy predicted 50 years. Cleaning required every 2-3 years.
Cost – Approximately 1% of the weight of glass, ETFE is designed to be very lightweight making it easier to transport and install while also requiring less structural framework. In addition, to being cheaper than glass, ETFE allows any tears and punctures in the material to be patched, rather than the entire film being replaced.
Lighting – ETFE is highly translucent, although not as much as glass. Cushions can distort the view.
110
What is an Aggregate Levy?
It is a tax on the commercial exploitation of rock, sand, and gravel
111
What are the different classification of waste soils?
Inert - not contaminated with any harmful substances and can be described as clean.
Non-hazardous soil - contains small levels of substances such as heavy metals.
Hazardous - have harmful quantities and can cause a threat to human health
112
What are the types of ground remediation methods?
Lime stabilisation, Capping, Soil disposal
