Construction Technology Flashcards

Question

What is a scaffold?

Answer 1

- Temporary working platform erected around the perimeter of a building or structure to provide a safe working place at a convenient height - Usually required for working above 1.5m high

Answer 2

- Form of support given to existing buildings. | - Precaution against damage or injury caused by collapse of structure.

Answer 3

Designed for the vertical transportation of materials or people

Answer 4

Foundations provide support for structures, transferring their load to layers of rock and soil that have sufficient bearing capacity.

Answer 5

- Permanent and static loads | - Predominately the structure itself

Answer 6

- Usually temporary - Changeable and dynamic - Occupants, furniture, equipment, vehicles

Answer 7

- The movement of air against the structure | - Particularly important on tall buildings and buildings with a light-weight dead load

Answer 8

Water, aggregate (rocks, sand etc), cement

Answer 9

Natural stone, crushed rock, gravel

Answer 10

- A borehole can be used for soil investigations or geothermal heating solutions - Boreholes are the most effective solution for soil investigations where the foundations are to be over 3m deep

Answer 11

Permanent holes that use the earth's natural heat energy to warm up circulated water. This is a closed system that can be used to heat the building above.

Answer 12

A series of columns constructed or inserted into the ground to transfer the load of a structure into the soil

Answer 13

- Replacement/Bored piles (reinforced concrete insitu) - Displacement/Driven piles (pre-cast, steel, composite) - Basement walls (secant piles, sheet piles)

Answer 14

- Sections of sheet materials with interlocking edges that are driven into the ground to provide earth retention or excavation support. - Typically made of steel - Often used for retaining walls and underground structures

Answer 15

- Intersecting steel reinforced concrete piles - Primary female piles are installed first, with secondary male piles installed in between them. Overlap of roughly 3 inches creating a flush finish - Useful in top-down construction and temporary waterproofing

Answer 16

- Auger is used to excavate soil, then concrete is poured in - Variation of this is where a continuous flight auger is used to bore piles and fill core with bentonite slurry. Concrete is then poured into core, displacing the bentonite slurry due to it's denser makeup. Rarely used now due to environmental impacts of bentonite - Minimal vibration

Answer 17

- Piles brought to site and hammered into the ground - High noise levels associated with installation - Lack of flexibility in terms of depth required

Answer 18

- End bearing piles: Pass through soft strata onto firm strata. Load transferred through toe of pile - Friction piles: Through sheer stress against side of piles - Tension piles: Through the length of the pile to reduce overturning moments on the building caused by uplift forces - Laterally loaded piles: Horizontal forces in situations such as bridge piers. Similar to above.

Answer 19

- In cohesive subsoils for the formation of friction piles | - When close to existing buildings due to noise/vibration limitation

Answer 20

- When there is soft soil deposits lying on firmer strata | - When noise/vibration isn't a concern

Answer 21

End depth of piles are never a certainty, procurement route determines who takes the risk. Traditional/D&B = Contractor Management Contracts = Employer

Answer 22

Used to spread the load of superstructure over a large base and reduce load/m2 of area. Generally reinforced concrete slabs.

Answer 23

- In low bearing capacity soils - Where settlement is likely - Where floor areas are small and structural load low

Answer 24

Shallow foundations used to provide a continuous, level strip to support a linear structure such as a wall

Answer 25

- Most subsoils | - Light structural design

Answer 26

A form of spread foundation formed by often square pads that support single-point structural loads such as columns

Answer 27

They act as an earth retaining structure for the whole or part of their height

Answer 28

Pressure of water/earth acting on wall

Answer 29

- Open - Perimeter Trench Excavation - Complete excavation

Answer 30

- Use battered excavation technique which is excavating the soil with the sides left at a safe angle so as to not collapse - Save money on temporary support work - Extra excavation costs due to extra soil being removed to ensure sides are at a safe angle - Requires free space on site for angled sides. Wouldn't work on site boundary.

Answer 31

Trenches are dug with required support around basement perimeter. Basement walls are formed, then inside of basement is excavated.

Answer 32

- Centre of basement is excavated - Basement slab is cased while sides of excavation are supported by struts - Basement walls formed - USED WHEN SUBSOILS ARE FIRM

Answer 33

A storey below ground floor.

Answer 34

a) Retaining wall and raft (monolithic) - slab raft foundation distributes building load. Basement walls are retaining. b) Box and Cellular - similar to above but internal structural walls transfer and spread loads over raft, dividing basement into cells c) Piled - superstructure load carried to basement floor by columns and treasferred into ground via pile caps & piles

Answer 35

a) Dense monolithic - basement designed to form watertight space b) Tanking - asphalt or similar resin applied internally or externally to provide continuous membrane to base slab and walls. External better as it protects substructure. c) Drained cavity - Accepts small about of water seepage, collects and drains this away. Inner non-load bearing wall forms cavity wall for water to drain into, CAN BE USED ON REFURB WORK

Answer 36

- Piston driven carbide tipped heads which impact surface at rapid rate - Removes thin layer from surface of concrete

Answer 37

- Roughen surface of concrete for better grip - Prepare surface for painting/sealing/coating - Reduce levels/level surface - Decoration

Answer 38

- Quick to assemble - Recyclable material - High strength to weight ratio - Not vulnerable to termites, fungi etc - Consistent material quality as produced in strict accordance with national standards - Non-combustible so won't contribute to spread of fire - Lighter than concrete

Answer 39

- Needs fire protection - Parts may need replacing - Price of steel is variable, could be high market dependent - Requires experienced builders - Will fail (collapse) before wood in a fire in spite of not being combustible

Answer 40

- Could be cheaper than steel dependant on market price of steel - Doesn't require additional fire protection - Slower construction will help cashflow - Low maintenance with insitu concrete frames - Cladding can be fixed to it and replaced easily - Good sound and heat insulation - Insitu allows alteration at later stages - Can deal with complex geometry better than steelwork

Answer 41

- Flange (top and bottom of the "I") - Web (the vertical steel, runs between the two flanges. Long part of the "I") - Root (where the flange and web meet)

Answer 42

Table that provides standard information on steel sections. Different table for different beams/columns, e.g. UB and UC.

Answer 43

10mm3 steel = 0.0078kg

Answer 44

- A durable factory applied organic coating on metals available in many colours - Polyester, acrylic, epoxy spray followed by heat curing - Any holes made/cuttings should be done prior to application of coating

Answer 45

- Stops corrosion - Stops abrasive damage - Stops metal reacting with other chemicals

Answer 46

Rectangular Hollow Section

Answer 47

Square hollow section

Answer 48

Universal beams & Universal Columns respectively

Answer 49

Fire resistant paint

Answer 50

- Plates, bolts or welding | - 5%-10% by weight

Answer 51

- A vertical strip or skirting, such as the weatherproofing where roofing meets an abutment wall. - It can be the roofing itself, particularly for mastic asphalt, the top part of a one-piece apron flashing, a mortar skirting or upstand flashing.

Answer 52

- Concrete - Power float is a hand-operated machine - Used to produce smooth, dense level surface finish to insitu concrete beds

Answer 53

- Post tensioning is a technique to reinforce concrete formed insitu - Can be used to join a series of pre-cast units - The concrete is cast around ducts or sheathing in which the tendons are housed - Steel tendons are pulled tight once concrete is cured using hydraulic jacks from one or both ends - The stretched steel tendons are then capped - Essentially, the steel tendons are pulling the concrete slabs together by trying to contract

Answer 54

- Anything that holds in-situ concrete in place until it hardens - Can be plywood shuttering, steel pan forms - Can be supported by props, centering (formwork for floors/slabs) or falsework

Answer 55

- A method for constructing repetitive structures such as a core, lift shaft or stairwell - Formwork constantly moves upwards at approx. 1 inch every 10 mins

Answer 56

- A significant height of concrete is cast and left to cure - The whole formwork is then moved up and action is repeated - Cheaper than slip forming but slower

Answer 57

Mesh used to reinforce concrete slabs. Metal lattice.

Answer 58

A damp proof course that crosses the 50mm wide cavity of the cavity wall, stepping up at least 150mm between the outer and inner leaves, to form a gutter that leads to a weephole in the outer leaf

Answer 59

A strip of impervious material the same width as brickwork or block work wall to stop moisture rising from the ground up the external leaf of the wall.

Answer 60

Through use of a lintel - a small beam over the window or door head to carry the wall load

Answer 61

Standard size - 215mm x 102.5mm x 65mm

Answer 62

- The frog is an indentation in one of the bed faces of a brick, usually the top - Bricks with two frogs are known as "double frogged", though these are less common - Bricks should be laid frog (or larger frog) facing up, with the mortar filling the frog - Creates a stronger wall and superior sound insulation

Answer 63

60 approx.

Answer 64

Flemish bond - The bond has one stretcher between headers, with headers centred over the stretchers below Stretcher bond - most common, walls just half a brick wide. Stretcher face side showing.

Answer 65

Stretcher = long side of brick face Header = short side of brick face Sailor = When bricks are stood up vertically, the wide face is called the sailor Soldier = When bricks are stood up vertically, the thinner face is called the soldier Rowlock Stretcher/Shiner = When the brick is sitting on it's stretcher, the wide face that was previously the top is called the shiner Rowlock = In the above situation, what was previously the head is called the rowlock

Answer 66

- Non-structural external surface - Protects everything inside from external weather - Formed of outer protective skin (metal, timber, glass, composite panels), supporting frame, a cavity and water-resistant internal materials which includes a layer of insulation - Three basic types are drained and ventilated, vented, and pressure equalised rainscreen systems

Answer 67

- Bolted (useful when may require being undone & cheaper than welding) - Riveted (fastest, like a nail) - Welded (melted together, maximum strength)

Answer 68

- M&E - Roof - Frame

Answer 69

A perforated brick to allow ventilation into a room or under a floor space. NOT A WEEP HOLE

Answer 70

- Fire rating requirements - Noise requirements (Db rating) - Visual requirements (glazing etc) - Flexibility required (movable/fixed) - Strength (to hang things from walls etc)

Answer 71

A recessed cut into a material to house another material e.g. glass, rebate for a smoke seal on a leading edge of a door or storm strip strip underneath

Answer 72

- Glass is fixed into a frame, steel or wood - Glass placed into a rebate, rebate is filled with putty/beading to hold it in place - This frame is then placed within walls/columns where required, usually held in with putty

Answer 73

Laid onto a ready prepared rough, cleaned concrete base

Answer 74

Laid onto a sound, clean Bitumen damp proof membrane

Answer 75

Screed laid on acoustic or thermal insulation. This is a type of unbonded screed.

Answer 76

A metal strip between the floor finishes or coverings that meet under the door leaf - Prevents fraying, creates a more fluid look and interrupts the spread of fire for combustible floors.

Answer 77

Apex beam in a roof.

Answer 78

The rafter extending from the wall plate to the ridge and forming the angle of a hip roof

Answer 79

The rafters that runs from the hip to the eaves

Answer 80

Run from the ridge to the eaves. Main structure of the roof.

Answer 81

Receive the feet of the rafters at the top of external wall

Answer 82

Horizontal beams that are used for structural support

Answer 83

Small lengths of wood that run between rafters horizontally. To these, the roof cover is fixed.

Answer 84

The rafters that runs from the hip to the eaves

Answer 85

Run from the ridge to the eaves. Main structure of the roof.

Answer 86

Receive the feet of the rafters at the top of external wall

Answer 87

Horizontal beams that are used for structural support

Answer 88

Small lengths of wood that run between rafters horizontally. To these, the roof cover is fixed.

Answer 89

- Slates - Pan tiles - Zinc - Copper - Thatched

Answer 90

Joists – fixed to wall plates to act as main support Firrings – fixed to the top of joists to give required incline Particle board (chipboard) – fixed to top of firrings to give flat surface Felt – 3 layers bonded with bitumen to give waterproof covering Stone chipping – To give protection to felt and to reflect sunlight

Answer 91

- One layer of felt consisting of a base sheet of glass fibre or polyester reinforcement, impregnated with hot bitumen during manufacture - Coated both sides with weatherproof bitumen compound - Easily punctured and rarely used - Cheapest option

Answer 92

- Constructed using three layers of a single layer membrane. - First is laid at right angle to the fall, second laid parallel to fall, third at right angle. - Covered with stone chippings - Easily punctured if care not taken - More common than single

Answer 93

- Aggregate with bituminous binder which is cast into block ready for reheating at site - Heated into cauldrons to 200 degrees Celsius (dangerous) - Transported in liquid form to roof - Two coats usually required - Reduce risks of defects as no risk of damage en route to site - Cools quickly, must be heated close to roof - Hard wearing and designed to allow transit. Some companies offer 60-year guarantee

Answer 94

- 3 hinges - Intumescent strip around door or frame - Self-closing devise - 6mm thick glass

Answer 95

Mineral fibre plasterboard suspended ceiling, typically used in office spaces

Answer 96

- Suspended ceiling system formed by square grid - Quick construction - Allow services to run through the voids allowing greater floor to ceiling height - Easy access to services - Damaged tiles can be replaced

Answer 97

- Rolled carpets generally better quality - More expensive - Used in dwellings.

Answer 98

- Hard wearing - Lower quality - Individual tiles can be replaced therefore easy to maintain - Used on offices - Easy access to flooring, useful when raised flooring is used

Answer 99

- Used to speed up construction for buildings with basement levels - Ground floor slab cased with access hatch - Ground below excavated and another slab is formed - Piles used as foundations and act as retaining walls. - Struts/propping required for retaining walls - This allows building above to be constructed at the same time as basement

Answer 100

- Forms the basement then works upwards in a traditional manner. - Simpler but longer programme

Answer 101

- Power supply connects to low voltage switchboard which in turn connects to a distribution board - The distribution board will have under floor busbar connected to it. The busbar has a number of sockets to which the floor box plugs into via a flexible lead. - The floor box has sockets which appliances can plug in to

Answer 102

A devise that directs electricity from one source to supply several smaller currents for further distribution

Answer 103

A devise that divides electrical power feed into subsidiary circuits while providing a protective fuse or circuit breaker for each circuit in a common enclosure.

Answer 104

- An AC supply that consists of three AC voltages - Enables a stronger consistent source of power - Used for lifts, big buildings. - Small electrical objects and houses do not need three phase electrical supply. Single phase eletrical supply fluctuates 60 times/second, so we do not see bulbs flicker etc.

Answer 105

Air Handling Unit Used to regulate and circulate air as part of a HVAC unit.

Answer 106

- Fan Coil Unit - Condition the local air to suit the temperature requirements of the immediate space - Main AHU will feed fresh air through main duct. Branches will flow off main duct into different rooms - Air will blow from duct into FCU (not directly connected, gap between duct and FCU allows for recycled air from grille in ceiling to be sucked into FCU also. - Air inside FCU gets sucked through fans, through heating or cooling coils, then out the other side

Answer 107

There are many plates in the FCU which pipes of hot water run through. This heats up the coils/plates/pipes. This heat is transferred to the air passing through. Could be electric rather than water.

Answer 108

Cold water from the chiller is fed through the cooling coil. The air transfers energy to the cooling coil, cooling itself down before flowing into the space As the air cools, it condenses. The condensation will run into a drip tray at the bottom of the FCU and a pipe will take it away. Could be a refrigeration unit instead of chilled water.

Answer 109

No, but each room must have at least one supply of fresh air. Regulations state a certain amount of fresh air is required, see Building Regs App F for detail for different building types.

Answer 110

Supply air is usually 100% ventilation air. - Air pumped into supply inlet and out of nozzles either side of chilled beam - This creates a low pressure zone that draws air into the face of the chilled beam. - This air goes through chilled beam (cooling coil similar to in FCU) and flows back out through the nozzle with more ventilated air

Answer 111

Chilled Beam: - Lower carbon emissions when first released, however not necessarily anymore due to advancement in FCU technology FCUs: - Cheaper than chilled beams - More flexible - Can heat and cool air

Answer 112

Concrete: - Waste materials can be included w/in mix, e.g. pulverised fuel ash - Short lead time - Slower to erect on site, though precast and improving methods are speeding this up - Fire protection is inherent - Most cost effective depends on the market. Steel fluctuates. - Requires steel reinforcement. Good compression strength but requires reinforcement for tensile strength - Can be moulded into different shapes but will struggle with open spans and/or high floor-floor height - Will not corrode. Steel reinforcement must be sealed/protected. Steel: - Long lead time - Fast to erect on site - Needs fire protection, prefab steel can allow for thin application off-site though - Lighter, as much as 60% lighter than concrete. Allows for less substantial foundations. - Less labour required to install - Strong, concrete lacks tensile strength - More flexible, good for long open spans due to strength - Requires protection from corrosion

Answer 113

Components that are attached to the primary structure of a building to form a non-structural, external surface

Answer 114

- Curtain walling - Rainscreen Cladding - GRC panels - Precast concrete cladding

Answer 115

- Glazed or opaque infill panels fixed to a lightweight frame - Vision panels, spandrel panels, aluminium panels, louvres/vents. - Fixed using stick or unitised system - Lightweight, maximise daylight, can provide good thermal performance (opaque panels) - Installation costs/maintenance costs can be high

Answer 116

- Stick system or unitised system - Stick system is where stick like frames are installed between beams, then panels fixed to them - Slow to install and require sealant around perimeter. Quality depends on skill of installers - Unitised systems are all-in-one panels that fix together between beams - Fast to install but long lead time due to prefabrication process. Cost a lot to ship and store.

Answer 117

- Concrete panels are formed off-site - Off-site manufacturing means it can be moulded into different shapes, colours, in controlled conditions so less wastage - Transported to site, tower/mobile cranes lift them to position - Panels can be fixed to frame or can be supporting itself

Answer 118

Glass reinforced concrete - Glass fibres imbedded in concrete matrix - Appears similar to natural stone - Can take any form - 80% lighter than steel reinforced concrete, therefore reduced installation costs - BREEAM A+ rating - Fragile in transport - Labour intensive to manufacture and can be expensive if bespoke (no economies of scale)

Answer 119

Masonry facades are generally load bearing facades made from brick/stone/block Benefits - Inexpensive to repair - Good to fire resistance - Good thermal mass and high acoustic performance Disadvantages - Can be expensive (block dependent) - Labour intensive and slow to install

Answer 120

Prefabrication is the practice of assembling components of a structure in a factory or other manufacturing site, and transporting complete assemblies or sub-assemblies to the construction site where the structure is to be located.

Answer 121

See Building Regulations K In schools: Flights of stairs - 0.9m from datum (standing level) Landings - 1.1m from datum

Answer 122

- Cupolas - Gargoyles - Chimney stacks - Cornices - Terracotta - Portland Stone

Answer 123

- Drain in the ground for rainwater to fall into. - Maximum paved area per gully should be 400m2 - Fall should be 1:60

Answer 124

- Long channel for rainwater to fall into - Fall should be 1:120 - Where the fall is all one way, away from a building

Answer 125

Approved document H

Answer 126

A pipe that takes waste water from toilets, urinals etc away from building. Ventilated.

Answer 127

Pipe that wastes waste water from sinks, showers, baths etc.

Answer 128

- Avoids flooding during heavy rain - Overflow of water in underground drainage overflows into perforated pipe - Water falls through holes into attenuation tank, where it is stored and slowly released

Answer 129

Approved Document B

Answer 130

- Intumescent paint - Intumescent strips on doors - Sprinklers - Fire doors that shut - Fire stopping voids between rooms to stop the spread of fire - Fire alarms

Answer 131

- Relates to the electrical control of systems - External conditions do not affect systems output, e.g. temperature will not affect whether AC comes on/off. It may be simply a timer. - Good because simple, easy to construct and stable

Answer 132

- Relates to electrical control of systems - External conditions affect system output, e.g. if the building gets too hot the AC will turn on - Good because they are intelligent and more useful, downside is they are more complex/difficult to install/expensive

Answer 133

- Refrigerant is pumped through pipes in liquid form - Refrigerant boils at low temp, so at room temp it turns into a gas - In turning into a gas, it takes energy from the air - The cool air is then blown with a fan into the room - The refrigerant gas is then condensed in a condenser (high pressure pushing the gas molecules together until they convert back into a liquid) - The now liquid refrigerant goes through an expansion valve to reduce the pressure before entering the loop again.

Answer 134

- Access Controller (decides whether people are allows in or out) - Reader (card, key pad) - Door contact (between door and frame, allows door to know whether it's open or closed) - Door strike/magnetic lock - REX (request to exit) allows you to leave without any card

Answer 135

End bearing = load transferred to rock/gravel largely at base of pile Friction = load transferred to ground largely through the sides of the pile (shear force)

Answer 136

- Cavity open at bottom - Provides drainage but no ventilation - Warm cavity, no ventilation (should be called drained really) - Warm cavity provides dew point close to outside - Shouldn't be used above 4 storeys due to higher wind load + greater risk of water penetration

Answer 137

- Not watertight - Cavity must be open at top and bottom - Cavity must provide drainage and promote ventilation - Protect cavity with overhang - Protect backing structure with moisture barrier (VCL) - Non-hygroscopic or closed cell insulation (PIR or Rockwool) - Excessively high D+V systems should be avoided (12m or less)

Answer 138

- Cavities are compartmentalised - Openings calculated to allow rapid ingress and egress of air resulting in very low wind load on panel themselves - Water ingress reduced by "equalisation" of internal and external pressures - Drained above compartment levelsS - Suited to tall areas of rainscreen, typically used over 4 storeys - Design intensive - Compartmentalisation stops spread of fire

Answer 139

1 - Some seepage/damp is tolerable. Car parks etc. 2 - No seepage is acceptable. Some damp is tolerable depending on use. Workshops, boiler rooms etc. 3 - No seepage or damp is tolerable. Offices, homes etc.

Answer 140

- BS defines as "barrier protection" - Material e.g. waterproof concrete applied to walls - Called "basement tanking" when applied to cellars/basements - Perfect for grade 1 waterproofing

Answer 141

- BS defines as the structure itself being a waterproof shell - a build of reinforced concrete supplemented with a method of controlling water ingress at construction joints (such as a hydrophilic waterbar) - Typically achieve grade 2 waterproofing, but that's not the limit of its application

Answer 142

- BS defines where a structure itself provides initial resistance against water, but also incorporates a drained cavity to collect groundwater ingress and direct it toward drain/pump for removal - Ideal for grade 3 waterproofing

Answer 143

The term given to a temperature rise within a space due to heat from the sun (solar radiation), heat from surfaces (long wave infrared radiation), heat originating from other sources within the space (such as heating appliances, ovens, people, mechanical systems, lights and computers)

Answer 144

- below 5 degrees takes longer to set - rain water into mix = bad - frost = bad

Answer 145

Grey water - water from sinks, taps etc Brown water - water from toilets

Construction Technology Flashcards

(170 cards)