Construction Technology and Environmental Studies - L3 Flashcards
Which RIBA stage is on-site construction?
RIBA Stage 5 – manufacturing and construction.
What is buildability?
– Buildability can be defined as the extent to which the design of the building facilitates the ease of construction.
– To help improve buildability, early contractor involvement should be considered to benefit from the experience and expertise.
What are the benefits of off-site construction over in-situ?
– 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 a factory can be scheduled to begin at the same time as other activities on-site, resulting in a shorter build program
What is the difference between building works and civil engineering works?
– Building works: all types of buildings such as houses, offices, shops, hotels, hospitals etc.
– Civil engineering works: drainage schemes, highways, culverts, bridges, retaining walls etc.
What are temporary works?
Temporary works are the parts of the construction project that I needed to enable the permanent work to be built, they are usually required for safety or access reasons. Examples:
– Propping.
– Scaffolding.
– Formwork.
– Excavation support.
What are hoists?
Designed for the vertical transportation of materials and/or people.
What is shoring?
Form of temporary support given to existing buildings and excavations. The purpose is to prevent collapse or excessive movement.
What is a culvert?
A culvert is a tunnel-like structure that is constructed to allow water to flow under a road by the way line or similar obstruction.
What is the purpose of a drainage headwall?
– A head wall is a small retaining wall/structure built at the inlet or outfall of a stormwater drainage pipe.
– They are used to protect the end of the drain as well as protect the watercourse embankment erosion.
What is a sub-structure of the building?
– Substructure is a lower portion of the building (in the ground) which supports the superstructure.
– Transmits the load of the building to the ground.
– Includes foundations, basement and retaining walls etc.
What is ground heave?
– Ground heave is usually associated with clay soil but 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 up.
What are some of the techniques available for ground improvement?
– Vibro compaction.
– Vibro stone columns.
– Vertical drains and vacuum consolidation.
– Soil mixing.
– Dynamic compaction.
– Dynamic replacement
What are the different forms of exclamation?
– Site clearance operations (removing vegetation and rubble).
– Stripping topsoil.
– Reduced level dig (to re-formation level).
– Cut and fill.
– Excavation for foundations.
What are the key factors the contractor should consider when excavating?
– Nature of the soil and moisture content of the ground.
– Method of excavation.
– If ground support systems are required.
– Proximity of existing buildings.
– Depth of excavation.
– Underground services and drainage.
Can you explain some of the techniques to waterproof the basement?
– Tanking – materials such as asphalt, polythene sheeting, pitchmen, etc. are applied internally or externally to provide a continuous membrane to the base slabs and walls.
– Drained cavity – this method accepts 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.
Have you come across the term SUDS?
– Sustainable urban drainage systems.
– SUDS are designed to manage stormwater locally (as close its source as possible), to mimic natural drainage and encourage its infiltration and/or attenuation.
– SUDS you’re in charge of them help to reduce the reliance on existing drainage infrastructure
Can you detail a typical Road build up please?
– Compacted and rolled type1 subbase (100 - 250mm).
– Base course (70 - 150mm)
– Blinder course (50–100mm)
– Wearing /surface course (20-40mm)
What is the purpose of a foundation?
– Foundations provide support for structures, transferring their load to the ground to avoid excessive settlement.
– Foundations should bare the loads of the superstructure.
What are the typical considerations when selecting the type and size of foundations?
– The total load of the building.
– Nature nature and load-bearing capacity of the ground.
– Type of structure.
– Cost.
– Construction constraints (for example, their proximity to adjacent buildings/structures).
What are the different types of foundations?
– Strip foundations.
– Pad foundations.
– Raft foundations.
– Piled foundations.
What is a raft foundation?
A raft foundation is essentially a continuous slab that extends over the entire footprint of the building. The raft spreads the load of the building over a larger area then other foundations, the stress acting on the ground below is reduced.
What a pad foundations?
– Pad foundations are typically used to support individual or multiple columns, spreading the load to the ground below.
– They are usually square oe rectangular on plan and can be reinforced on nonreinforced.
What are strip foundations?
As the name suggests, the formation is in a strip of linear structure that ultimately serves to spread the weight across the total area of the ground, typically used to support masonry.
What are piled foundations?
– A pile is a column (usually concrete) that extends deep into the ground.
– Where the bearing capacity of the soil is poor or imposed loads of very heavy, piled foundations may be required.
– There are two main types of piles: end-bearing piles and friction piles.
– There are two main construction methods: bored piles and driven piles.
In what scenarios might a piled foundation be the best solution for the project?
– What a structure is heavy and the underlying soil is weak.
– In areas where settlement issues are common.
– Where the subsoil water table is high.
– Where the lower distribution of the structure is not uniform.
– Presence of horizontal forces.
Can you explain how end bearing and fiction 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 – fiction piles work on a different principle, fiction piles develop most of the pile-bearings capacity by shear stresses along the sides of the pile. In other words, the surface of the pile works to transfer the forces to the soil.
What are the differences between bored piles and driven piles?
The fundamental difference lies in their point of manufacture. A driven pile is formed off-site under factory-controlled conditions and a bored pile is manufactured on-site.
What are the key advantages of different piles?
– Piles can be precast to the required specifications.
– Piles of any size, length and shape can be made in advance.
– A pile driven into granular soil compacts the adjacent soil mass, the bearing capacity of the pile may increase as a result.
– Fast, neat and clean installation.
What are the key disadvantages of driven piles?
– Requires heavy equipment for handling and delivery.
– Increased noise and vibration is generated by driving the piles.
– Can be costly if piles are too short.
What are the key advantages of bored piles?
– Any size or shape of piles can be formed on-site.
– No risk of damage during delivery and handling.
– Reduced vibrations and noise.
What are the key disadvantages of bored piles
– Significant spoils are generated that need to be handled.
– Reliance and coordination on multiple trades (reinforcement crew, piling crew and concrete supplier).
– Unlike driven piles, bored piles do not improve the bearing capacity of the ground.
What are secant pile walls?
– A wall is formed by installing interlocking piles which create a solid barrier free of gaps.
– Typically used to form a retaining wall.
What is underpinning and why might it be required?
– Underpinning is a method for repairing and strengthening the foundations.
– Stabilising foundations undergoing settlement.
– Stabilising foundations that have moved because of landslip or unstable slopes.
– Stabilising foundations affected by erosion, subsidence, or heave.
– Stabilising foundations affected by vibration damage.
– To increase the load capacity of existing foundations.
– To accommodate a new adjoining building, new basement, or deep sewer.
What is the superstructure of a building?
– Structural components of a building constructed above the ground level (usually everything above damp proof course).
– The basic components of the building superstructure of columns, beams, slabs, walls etc.
What is the envelope of a building?
– A building envelope is the boundary between the interior and exterior of the building.
– The materials and components that form the external shell of a building such as brickwork, cladding, curtain walls etc.
What are the key considerations when designing external walls?
– Weather protection.
– Fire resistance.
– Acoustic and thermal performance.
– Structural performance.
– Appearances/aesthetics.
– Expected lifespan.
– Future maintenance.
Can you briefly explain what a retained facade is?
– The facade of the building is preserved whilst the rest of the structure is remodelled, or a new structure is built behind it.
– Facade retention is often used when restoring listed buildings.
What are standard brick dimensions in the UK?
215mm x 102.5mm x 65mm
How many UK standard-size bricks are required per sqm?
60 bricks per sqm
How many UK standard-size blocks are required per sqm?
10 blocks per sqm
What are weep holes?
– Small openings in the outer skin of masonry construction.
– Weep holes provide ventilation to the cavity and allow moisture to drain away.
Can you name two different types of brick bonds?
– English bond –alternating courses of headers and structures.
– Stretcher Bond – the most common brickwork method. The vertical joints are staggered each time by half a brick.
What is a curtain walling system?
Typically, curtain wall systems comprise of a lightweight aluminium frame onto which glazed or opaque infill panels can be fixed.
What is a movement joint why are they used?
– A movement joint is designed to safely absorb the expansion and contraction of construction materials.
– Movement joints can also allow for movement associated with ground settlement or seismic activity.
What are the key differences between wet rot and dry rot?
Wet rot and dry rot are two different types of fungi. One of the main differences between them is that wet rot needs a higher moisture content to grow. Wet rot fungus likes to grow on timber with a high moisture content of around 50% and above, while for dry rot to grow, it will germinate at a lower timber moisture content of around 20 to 30%.
What are the key characteristics of wet rot?
– Wet and spongy to the touch.
– Affected timbers will appear darker.
– Localised fungal growth.
– Affected timber is vulnerable to shrinkage.
– More likely to be accompanied by a damp, musty smell.
What are the key characteristics of dry rot?
– Dry and brittle timber appearance.
– There may be orange spore dust.
– White strands (known as hyphae).
– White or grey cloud-like structures.
– Rusty brown fruiting bodies.
What are the main components of concrete?
– Cement.
– Aggregate.
– Water.
What is the difference between dead loads and live loads on a structure?
– Dead loads are static forces that are relatively constant for an extended time; usually the weight of 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, movable equipment etc.
What are retaining walls?
A retaining wall holds back (or ‘retains’) the soil behind it. The typical purpose is to resist the lateral pressure of soil where there is a change in ground elevation.
What is pre-tensioned concrete?
– In pre-tensioning the reinforcement, in the form of tendons or cables, are stretched (put into tension) across the concrete formwork before the concrete is placed.
– After the concrete has hardened and a suitable strength developed, the tendons are released.
– The tendons attempt to shorten and transfer the energy stored to the concrete.
– A compressive force is therefore induced into the concrete.
What is post-tensioned concrete?
– The concrete is cast around tubes or ducks which will contain the reinforcing tendon.
– Once a suitable concrete strength has developed, the tendons of threaded through the ducts and stretched (put into tension) using hydraulic jacks.
Can you explain what a ghulam beam is?
– The term ghulam is an abbreviated term that stands for glue-laminated timber.
–a Ghulam is made with multiple layers of solid wood bonded together with high-strength adhesive to form a single structural unit.
Can you explain what reinforced concrete is?
– Reinforced concrete is a combination of concrete with reinforcement (Usually steel bars, rods, or mesh).
– This combination is made to use the compressive strength of concrete and the tensile strength of steel at the same time, hence, working together to resist many types of loading.
What are the key advantages of timber frames?
– Construction on site can be faster (compared to in situ concrete frames).
– The structure is relatively lightweight.
– Timber can be aesthetically pleasing (exposed oak beams for example).
– Sustainability benefits (assuming the timber is harvested responsibly from well-managed forests).
What are the key disadvantages of timber frames?
– Skilled workmanship is required to achieve a high-quality finish.
– Potential for wet rot, dry rot and woodworm etc.
– Fire protection may be required.
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 (Ideal for warehouses etc).
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 be volatile.
– Steel frames do not have the same acoustic and thermal properties of a concrete frame.
What is a portal frame and what type of buildings are the most suitable for?
– The frame is generally character restaurants I have been (Or rafter) supported at either end by columns. The columns are typically connected to the rafters with haunch/Eaves connections.
– Portal frames usually have long clear spans providing large areas of open space; therefore, they are commonly used to construct warehouses, factories etc.
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 installation.
– High compressive strength.
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 is typically achieved after 28 days.
With reference to concrete frames, what is formwork?
Formwork is a structure, usually temporary, used to contain poured concrete a mould it to the required dimensions. Formwork is usually stripped away once the concrete has hardened and can support itself.
What key factors should be considered when selecting the type of structural frame?
– Program requirements.
– Fire protection.
– Acoustic and thermal properties.
– Market conditions and supply costs.
– Site logistics and general site constraints.
– End user requirements (Necessity for column-free space).
– Sustainability objectives such as BREEAM certificate.
– Mechanical and electrical services strategy.
– Future expansion requirements.
What is slip form construction?
– Slipform construction involves pouring concrete into the top of a continuously moving from work. As the concrete is poured, the formwork is raised vertically at a speed that allows the concrete to harden before it is exposed at the bottom.
– Typically used to construct their calls, lift shafts, towers etc.
What is jump forming?
Jump forming works in a similar principle to sleep form. 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.
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 including fixing details.
– Robustness.
– Height of the partition.
what is a CAT A fit out?
– CAT A fit out typically provides a basic level of finish, this may include raised floors, suspended ceilings and petitions, along with basic mechanical and electrical services.
– CAT A space is often a barebones finish that is considered a blank canvas print area and office designers. The next phase of the fit out is CAT B.
What is a CAT B fit out?
– CAT B fit out provides a space that is ready to move into and operate.
– CAT B fit out can include but is not limited to:
– Partitions and doors.
– Floor finishes.
– Specialist lighting and facilities.
– Cafés tea. And kitchen areas.
– Furniture.
– Branded material and decor.
Can you name some common types of plasterboard?
– Standard boards (white/light grey).
– Fire boards (pink).
– Acoustic board (blue).
– Moisture resistant boards (green).
What is raised access flooring?
A floor sitting on pedestals above the structural slab. The system allows services to be located within the void (usually power and data cables).
Can you explain the difference between single-phase and 3-phase electrical supplies?
– Single-phase power has just one live wire whereas 3-phase power users three live wires, both will also have one neutral wire and in almost all cases an earth wire too.
– As such, 3 3-phase power supply is a more constant, reliable current.
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.
What is a UPS and why might the client require one?
– Uninterruptible power supplies (UPS).
– The UPS provide an alternative ‘no-break’ electrical supply in situations where it is important there is no loss of electrical supply, even if the primary supply fails.
– Typically installed in hospitals for life-critical equipment, data centres and IT server rooms.
What does HVAC stand for?
Heating, ventilation, and air-conditioning.
What does FCU, AHU and VAV stand for?
– Fan Coil Unit (FCU).
– Air Handling Unit ( AHU).
– Variable Air Volume system (VAV).
What is natural ventilation?
– Natural ventilation is a method of supplying fresh air to building a room by means of passive forces, typically by windspeed or differences in pressure internally and externally.
– This is achieved without the use of mechanical systems, therefore reducing carbon emissions is a key benefit.
What is mechanical ventilation?
Mechanical ventilation is the intentional fan-driven flow of outdoor air into the building. Mechanical ventilation systems may include supply fans (pushing outdoor air into a building), exhaust fans (drawing air out of the building), or a combination of both.
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, and then transfers the heat to the heating system.
- The function resembles the workings of a fridge or air-conditioner, but in reverse.
Can you explain how siphonic drainage systems work?
– Siphonic drainage systems contain an anti-vortex plate which acts as a baffle and prevents air (and debris) entering the piping system at full flow, allowing the pipes to completely fill up with water.
– The water is sucked or siphoned from the roof down into the drain at high velocity. I lack of air and the downward pull of the water creates a vacuum, making a drainage process fast and efficient.
What is rainscreen cladding used for?
– A rainscreen uses an exterior surface – rainscreen cladding layer – to break the force of sideways, wind-driven water movement so that any water that gets through the small breaches in the surface has lost its momentum. Most water simply bounces off the surface of runs down the exterior.
– The system is not necessarily waterproof itself but serves as a screen and protection against rain for the rest of the building.
– Two key types of system:
– Drained and ventilated systems.
– Pressure equalised systems.
What is the purpose of the parapet?
– A parapet is an extension of the external building shelves above roof level.
– A parapet can be used as edge protection to enable maintenance to take place and can also mask unsightly roof plant from ground level.
What is the difference between a gable, hipped and mansard roof?
– Table – a roof sloping downwards into parts at an angle from a central ridge.
– Hipped - A roof that slopes upwards from all sides of the structure having no vertical ends.
– Mansard roof –steep front face pitch with a shallow pitch/flat roof on top.
What surveys might be required for a typical construction project?
– Topographic survey.
– Site investigation.
– Asbestos survey.
– Drainage CCTV survey.
– Utility searches.
– Measured survey.
– Ecology surveys.
– Flood risk assessments.
– Transport assessments.
– UXO discovery.
– CBR test.
– Archaeological digs/excavations.
– Existing condition surveys.
What are the objectives of the 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.
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 (such as roads).
What types of vegetation can cause issues for a construction project?
Invasive plants such as Japanese knot weed.
Are you aware of RICS professional standard associated with Japanese knotweed?
Japanese knotweed and residential property – 1st addition, January 2022.
What fire safety provisions much you find in the new building?
– Maximum occupancy numbers.
– Fire evacuation plan, designated escape routes (with signage) and fire exits.
– Fire extinguishers.
– Fire alarms.
– Sprinklers.
– Firedamp and is located in ventilation ductwork.
– Fire barriers in floor, walls and ceiling cavities.
– Fire-rated roller shutters.
– Smoke control systems.
What is a fire compartmentation within 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.
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.
What are automatic fire sprinklers and how are they activated?
Sprinkler heads are usually heat-activated. When the heat of the fire reaches a sprinkler head, I 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.
Can you detail the different types of fire extinguisher and their typical uses?
Water – would, cardboard, textiles.
Foam – flammable liquids.
Dry powder – flammable liquids and electrical fires.
Carbon dioxide – electrical fires.
Wet chemical – cooking oil fires.
What is a man safe fall arrest system
– Man safe systems are horizontal or vertical safety lines (usually stainless steel wire rope) designed to keep people safe whilst working at height. The user will wear a safety harness and clip onto the safety line.
–if I fall should occur, the system is designed to limit the distance and consequence of the fall.
What are building regulations?
– Regulations to ensure that new buildings, conversions, renovations and extensions (domestic or commercial) are going to be safe, healthy and high-performing.
– Regulations cover specific topics including structural integrity, fire protection, accessibility, energy performance, acoustic performance, protection against force, and electrical and gas safety.
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 safety 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 networks.
Part S – Infrastructure for charging electric vehicles.
Part T - Toilet Accommodation.
Approved document seven – materials and workmanship.
Who reviews the design and construction phase for compliance with building regulations?
The building control officer or approved inspector.
What are British standards?
– Publications issued by the British Standards Institution (prefixed BS).
– They have recommended minimum standards for materials, components, design and construction practices.
Can you name some materials that have been banned from using construction?
– High alumina cement in structural elements
– Asbestos
– Urea formaldehyde
What is the Equality Act 2010?
– The Equality Act 2010 legally protects people from discrimination in the workplace and in wider society.
–The Equality Act replaced previous anti-discrimination laws with a single act and covers all matters such as disability, race, sex, gender reassignment, pregnancy, religion, or belief etc.
How does the Equality Act affect buildings?
– Whilst accessible design of buildings is regulated by Building Regulations Part M, the Equality Act does require ‘reasonable adjustments’ to be made from providing access to goods, a set of things, services and premises.
– This means due regard must be given to any specific needs of likely building users. Compliance with the requirements of Part M does not therefore signify compliance with the much broader obligations and duties as set out in the Equality Act.
Can you explain what the Party Wall Act 1990 is?
– The party wall etc 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 or building regulations approval.
What is the Fire Safety Act 2021?
– The Fire Safety Act 2021 (the Act) received Royal assent on 29 April 2021 and commenced on 16 May 2022. The act amends the regulatory reform (Fire safety) order 2005 (the Fire Safety Order).
– The Fire Safety Act 2021 clarified that the responsible person or duty holder for multi-occupied, residential buildings must manage and reduce the risk of fire posed by the building structure, and most notably external wall systems, including windows and balconies, and individual occupants’ entrance doors.
– The new act is an effort on behalf of the Government to improve fire safety in multi-occupancy domestic premises following the tragedy at Grenfell Tower in 2017.
Can you briefly explain what O& M manuals are and what might be included?
– Operation and Maintenance manuals. Upon completion of the building phase, O&M manuals are issued to the client/building owner (O&M manuals are usually 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.
