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Week 6

Key terms

Alloy: a mixture of a base metal and another element to make a stronger alloy, with

different characterisitics. Examples of alloys are: Iron+ Carbon = Steel, Lead + Tin =

Solder. Photo source:

http://www.electronicstheory.com/COURSES/ELECTRONICS/soldering2.htm

Cantilever: A beam that is only anchored, or fixed, at one

end. This means one end of the beam hangs out suspended

over the space underneath, similar to a balcony or eave. An

example is the new Architecture building at Melbourne

University.

Eave: The bottom edge of a roof that protrudes beyond the wall of a

building. Is used to keep water off the surface of the structure, or

shading for the outside of the structure. Photo source:

http://paulaablesinteriors.com/?p=741

Soffit: is an outdoor ceiling. Soffits can be the undersides of eaves, verandahs or cantilevers. Soffits can be made of a

range of materials, from timber to treated plasterboard. Photo source: http://www.jandjbuildingproducts.ca/soffit

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Top chord: The highest linear component of two dimensional truss, that is connected to the lowest linear component

(bottom chord) by diagonal webs. If the truss is used in a roof system, the roof cladding will be fixed to purlins that are

positioned immediately above the top chord. The top chord is under compressive forces.

Portal frame: Construction method use

commonly for larger spans, that are low rise

structures – meaning their roof is on a minor

angle they often use a thin steel roofing cladding.

The structure generally uses both structural hot

rolled steel columns and beams, as well as cold

form steel, and concrete is used for foundations

and sometimes to lay an internal wall layer a few

metres tall for security and workplace safety and

protection of the building. Portal frame

structures use rigid joints and the bending

stiffness of its members to provide the strength to

span large distances (Portal Frames, 2013). Due to

this spanning ability, portal frames are used in

larger industrial and agricultural buildings.

Image sourced:

http://www.steelconstruction.info/File:L_Fig11.png

Rafters: are sloped structural members that support a roof.

At one end the rafters meet at the ridge (the central and

highest up horizontal beam) and at the other end meet the

wall system, and generally sit on the ‘top plate’ if the wall

system is a timber framed one. Rafters support the weight of

the roof cladding, and the angle at which they are on is

generally the angle the roof will follow.

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Purlins: a horizontal structural member in

a roofing system, that are also used in

wall systems as well. In a roofing

scenario they interlock with rafters or

trusses to create a frame for the roof

cladding to be fixed to. Used in both flat

and angled roofing systems, used to

support roof cladding, which is fixed

directly to it. Can be made from timber

or cold formed steel. Generally

galvanised if steel, as they are not very

thick. Can come in a range of different

cross sections. Purlins used in walling systems

are the link between each structural column.

In this photo the purlins are the silver horizontal

beams, connected by smaller rods that prevent

twisting of the purlin.

Source: http://www.bw-industries.co.uk/roof-

purlins.htm

TRUSSES: Trusses are a formation of materials that uses triangulation and both forces of compression and tension to be

able to span a long distance. Trusses come in different shapes and sizes but all have at least 5 triangulated joints. Trusses

are used in the industry for spanning long distances, or allowing for a gable for a roofing structure. The increased

spanning and incredible strength provide by the triangulation means that trusses are used in larger scale engineering

projects such as bridges.

Image source: Brookefield Bridge, Indian Creek, Oxford.

http://www.bceo.org/bcimages.html

As trusses span long distances, the bottom chord is under

tensile forces, as applied weight naturally bends a

material. As the bottom chord is fixed to the top chord in

multiple places, it cannot bend anywhere nearly as much as

it normally would, and in turn the top chord is

compressed.

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Trusses can be made from either wood, or metal. The joints (nodes) differ depending on the chosen material. If the truss

is wooden, nails and perforated metal joints. If the joint is metal, bolts or welds are generally used.

Different types of trusses:

1. Flat truss. This is also classified as a ‘Pratt’. A Pratt truss is one that has vertical webs in compression, and

diagonal webs in tension. Note that all Pratt truss webs meet at the bottom (in the very middle), whereas

‘Howe’ truss webs meet at the top (in the middle).

Flat trusses such as this one are not as efficient as pitched or curved trusses.

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2. A pitched ‘Pratt’ truss. (Black)

3. A pitched ‘Howe’ truss. A Howe truss is the opposite to a Pratt truss, as the vertical webs are in tension and

the diagonal webs in

compression. The

Howe truss is

represented in red.

4. A ‘Warren’ ‘Bowstring’ truss. A Warren truss is a truss that has webs positioned so they form a series of

equilateral triangles. A bowstring truss has a curved top chord, and a straight bottom chord.

PLATES AND GRIDS:

What is a plate? Rigid planar structures that disperse applied loads in multiple directions, generally to the closest

structural support. Example of a plate structure is a reinforced concrete slab.

Photo source: http://www.nexus.globalquakemodel.org/gem-building-

taxonomy/overview/glossary/cast-in-place-beamless-reinforced-concrete-

roof--rc1

When a load is applied load to a plate it is distributed around, which in turn

stiffens the whole structure due to the torsional resistance of the

surrounding internal strips. Plates work best when their shape is close to

square, and they can easily stick to a two way distribution of applied weight.

Plates are used in floors, roofs, and walls.

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Folded plates, despite being made from thinner material, are stiffened and strengthened immensely when folded. By

folding into a zigzag shape, each individual plane acts as a beam in the longitudinal direction (see A in diagram below),

where in the perpendicular direction the span is reduced (see B), and so the material remains much more rigid as metal

is stronger when covering a shorter distance. This same concept is seen in corrugated iron (which is actually a steel), a

common roofing material made from cold formed steel.

Image source: http://www.musgroves.co.nz/shop/show_single_product.php?prod=96

GRIDS:

Lines on a grid represent principal points and lines of

support for a structural system. Horizontal beams and

loadbearing walls and pillars are represented by the lines on

the grid, from which 3D images can be drawn. Grids are

used in the design process of a building, with CAD

(computer assisted design) programs utilising a grid on

which to build the virtual building. The relationship

between grids and plates is that plates can be

represented on a grid.

Image source: http://www.shutterstock.com/pic-

79531561/stock-photo-concept-of-designing-and-

building-an-industrial-factory-or-a-warehouse.html

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ROOF SYSTEMS:

All roof systems are pitched on an angle to allow runoff of collected water. Even flat roofs are pitched to 1-3⁰ to ensure

that ponding (forming of puddles on the roof structure) does not occur. Ponding can stress the structure as it is a dead

load directly on the roof. Some materials are better suited for smaller pitched roofs, such as concrete and metal. Tiles

need to be pitched at greater than 15ᵒ to ensure that the water does not work its way back into the roof.

The main function of a roof is to keep the weather out of the building it is positioned above, and so must be suited to

the conditions that the house is in. For example, if the building is in a heavy snow effected region, a high gabled roof

should be used in order to prevent ponding of snow.

Flat roofs may consist of reinforced concrete slabs, steel or timber truss, timber/steel beam + decking, or wood/steel

joists + sheathing. On the other hand, sloped roofs may consist of wood/steel rafter + cladding, timber/steel beams,

purlins and decking or timber/steel trusses.

Some roofing materials include concrete, metal, slate, tiles, and earth.

Images Top right (slate)and top left (metal sheeting) , bottom left (clay based tiles) sourced from: http://www.home-

style-choices.com/roofing-materials.html

Bottom right (concrete) sourced: http://www.connoisseurroofs.co.za/concrete-roofs.htm

Concrete Roof

Cement roofs are generally a flat plate

of reinforced concrete that is angled

slightly to a drainage point. As

concrete floors weigh a considerable

amount, they are supported by other

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concrete structural columns. Concrete roofs are not just bare concrete, a layer of lightweight insulation is applied on top

of the trowel smoothed surface, then a waterproof membrane (similar to that used when tanking) is applied, then a

layer of ‘wear course’ is applied, to take the brunt of the weather, and to take any scratches on roughages that may

happen on the surface of the roof. This wear course is crucial, as a tear in the waterproof membrane could lead to

ponding in the insulation.

Structural steel roof

A structural steel roof uses a mixture of primary members (structural hot rolled steel) and secondary members (cold

formed steel) to create a frame for a roof cladding to be fixed to. Depending on the slope of the roof will determine

what cladding will be used, if the roof is flat and concrete will be used as cladding, only primary members will be used –

due to the strength of the members. When the roof is sloped the mixture of the two materials will be used, with the

metal cladding being attached directly to the purlins.

Using smaller cold formed sections (purlins) to connect the hot rolled rafters, or joists (depending on the angle of the

roof) allows for the roof cladding to be fixed to the structure. It is due to this that lines of screws are visible from the

outside of a structure. Above image source: http://alphaomega07.wix.com/007#!__page-5

Truss roof

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A Truss roof is used in both domestic and industrial settings, to span a long distance between walls – providing a large

open area underneath.

Image sourced:

http://trusseswales.wordpress.com/2012/03/30/a-comparative-review-of-timber-frame-roof-systems/

Hip roof

When a roof wraps around a corner at a right angle, and presents a triangle end.

Image sourced: http://roofframer.com/hip_roof.htm

Gable roof: rafters on a gable roof directly meet and are

connected to one another, and the ridge board is a non-structural member.

Metals:

Metals are malleable and ductile, due to the way they are atomically formed. They

become even more so when they are heated up. Ferrous metals: relates to any

metals that has iron in it. Because iron is such a popular element ferrous metals

The GALVANIC SERIES relates

to a scale of which metals

have a higher likelihood of

corroding when put in a

electrolytic situation. In order

of most likely to corrode to

least:

Magnesium, zinc, aliminium,

structural steel, cast iron,

lead, tin, copper, brass,

bronze, nickel, titanium,

stainless steel

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are relatively cheap. Understandably non ferrous metals are metals that do not include iron. These are generally more

expensive. The properties of metal vary with different kinds of metal, for example hardness-wise lead is easily

scratched, whereas gold is not. Metal as a whole is not fragile, but does have high ductility. Metal is also generally

impermeable – which is the reason it is used in drainage systems. Metals are excellent conductors of heat and

electricity, which is why metal is used in electrical cables. Metal has a tendency to corrode when in contact with other

sorts of metals, or moisture. To battle this precautions such as galvanising, using gaskets between metals, or covering

the surface with paint.

Ferrous materials have strong magnetic properties, and strong compressive strength. The inclination to corrode and rust

is due to ferrous metals being very chemically reactive. A commonly known ferrous alloy is made from mixing Iron and

Carbon, that alloy being Steel. A strong element, steel can be found in many different shapes, with different processes

to get these shapes.

Structural steel: includes hot formed structural steel, which is

rolled when red hot, and produces a strong heavy material that is

used as a primary construction material. To protect this metal from

corrosion some members are painted, but due to the fact that they

are so heavy and theoretically once the building around them has

been finished they should never see the weather again many are

not treated with paint or any protective hot dipping. Hot rolled

steel photo sourced: http://designbuildsource.com.au/steel-

makers-embrace-sustainability

Hot rolled steel profiles. The two identical elements are called a ‘flange’, they are connected by a ‘web’.

Cold formed steel is used as a secondary construction material, and due to its smaller size is often treated for weather

resistance, behind hot dipped in zinc, galvanising its surface. Examples of cold formed steel are purlins or gurts (wall

purlins), most smaller RHS or pipe.

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Reinforcing bars for concrete are made from steel because of steel’s good tensile strength. These reinforcing bars are

deliberately deformed, with undulating surfaces design to cling to the surrounding concrete. Steel sheeting is often used

for cladding/roofing, although before it can do this it needs to be protected (via galvanization/paint). Steel sheeting is

used because it is lightweight, strong, resistant to weather (if treated), and is easily applied. Stainless steel is the result

of mixing steel (iron+ carbon) and chromium. The minimum 12% chromium within the alloy gives characteristics such as

high resistance to weather and corrosion sources, if scratched the scratch it seals itself over, and incredible sanitary

qualities, hence stainless steel being used in hospitals and kitchens.

NON FERROUS METALS:

Aluminum is lightweight and strong, and easily formed. Extruded

aluminum windows are strong and very efficient, in terms of

material use. Aluminum’s matt colour comes from its strange

characteristic, which makes it self oxidise upon contact with

oxygen. Extruded aluminum, image source: http://www.pa-

international.com.au/index.php?article&id=128&Itemid=173

Copper is a really good conductor of electricity, and so it used in

electrical wiring. Copper is also incredibly malleable, which allows

it to be used as a roof cladding – which changes colour to a green

shade when exposed to the weather over time.

Zinc is mainly used for galvanising cold formed steel, but can be used as cladding by itself. Titanium: can be used as a

cladding, however is ridiculously expensive and so this is only done rarely. When it is used as cladding it is very

successful, as titanium has a high strength to weight ratio, and is very resistant to corrosion. Brass is a very tough

material, and due to this is used where friction occurs regularly, for example gears, locks or valves.

Below right: Structural UB. This is hot rolled structural steel.

Sourced: http://www.scrapmonster.com/metals/finish/steel-

beam/steel/3 Below left: Cold formed steel purlin sections.

Sourced: http://rebelsteel.com.au/products.php

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In Studio

Brunswick East townhouse

- Double story brick veneer house. Has a balcony

that is a cantilever, weight supported by UB.

- Concrete slab for the second floor is made in

waffle-slab design (see right)

- All walls use hoop iron bracing

- All foundations have been tanked (wrapped in a

waterproof membrane to prevent water damage).

Above image sourced from:

http://www.studyblue.com/notes/note/n/e-tech-i-

concrete-test/deck/1499202

12 Palmerston Place Carlton

- 6m deep piers dug, reinforced

then cemented at edge of site to

solidify ground, concrete pumped

under bluestone of footings of

neighbours house.

- Site dug out to start building.

Concrete mesh on chairs pours

slab for the underground cellar.

- Corefilled blockwork braced with

wood while it sets in positions.

Cavities around now set cellar

filled in with screenings,

underneath screenings is an AGI

pipe (agriculture pipe that is

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perforated to capture water to then transport away off site).

- PVC pipe visible coming out of the completed cellar.

Reference list: Portal Frames (2013, December) Retrieved from

http://www.steelconstruction.info/Portal_frames

Week 7

Key terms:

Drip: A notch or angle that causes breakage of surface tension, forcing the water to fall off the material. Use of drips

prevents water, carried by capillary action, to cling to the building, potentially going back onto the surface material and

penetrating. There are many different types of drips, but all are used to stop water getting into the building.

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Parapet: where the wall continues above the level of the roof. A parapet can be used to protect things from falling off

the roof, as protection from fire, a guard rail, architectural appeal or historically speaking, shelter for soldiers protecting

a castle/wall.

Gutter: part of the drainage system. Gutter is generally (U section) folded metal hung that is on an slight angle (so the

water still runs in a guided direction) next to a roof, that collects the water directed down to it by the slope of the roof,

and then transports the water away. Can be positioned next to or inbetween roofs, although this gutter is known as a

box gutter.

Down pipe: A down part is another of the roof drainage system, a

downpipe is generally a vertical pipe attached to the lower end of gutter, that directs the water collected by the gutter

down, either into a tank or to a release point.

Flashing: Flashing is folded metal that covers gaps in a wall or roof, including joins such as the ridge. Ridge capping is a

form of flashing. Flashing stops the elements getting into holes, and is also useful at securing the shell structure.

Insulation: Insulation is any material that helps suppress or stop transference of heat and noise through walls or roofs

on a building. Insulation can come in the form of batts, or can be made from expanding foam, or even sarking.

Source: Batt

http://www.findenergysavings.co.uk/free-

cavity-wall-insulation-services-grants

Spray http://www.ryan-ws.com/attic-insulation-minnesota.php Sarking ebay.com.au

Sealant: A sealant is a solidifying liquid product that is used to small fill gaps between materials to prevent the entry of

dust, heat, air, insects, fire or smoke.

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Detailing for moisture:

3 main approaches to preventing water getting in a building:

1. Remove openings

2. Keep water away from remaining openings. Eg. Eaves/flashing/drainage system

3. Neutralize forces that move water through gaps and into the building

Keeping underground water away from a building can be tackled by either tanking, covering the building in a waterprrof

rubber membrane, or by use of an agricultural pipe, a pipe running adjacent to the building that collects water that has

worked its way through the rock filing above, and transports the water away to a storm water drain.

Right: covered agricultural pipe runs around the edge of a house. Sourced:

http://forum.homeone.com.au/viewtopic.php?f=31&t=32840

Right: a black waterproof membrane covers the house up to ground

level. Sourced: http://www.network-roofing.co.uk/tanking.html

Cavity wall flashing stops water that breaks through the first layer of a

cavity wall. Any water that does gets caught by the angled flashing

which then directs the water back out through the wall, through an

open perpernd, also known as a weeper joint.

Weeper joint,

sourced:

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http://inspectapedia.com/structure/Brick_Wall_Weep_Holes.htm

Neutralising forces that move water through gaps in a building surface can be done by inserting pressure equalization

chambers in rain screen assemblies.

When heavy rain or wind is forcing water into gaps with extra force than normal into the lower pressure of the inside of

the building, putting a air barrier on the internal side of creates a pressure equalization chamber, and in doing so takes

away the momentum of the water, as it loses its pressurised pumping action, and falls back out the way it entered.

Detailing for heat:

- Thermal insulation

reduces heat transfer through

surfaces, by installation of

different types of insulation.

Eg. Batts, foam or sarking.

- Thermal breaks –

inserting a less conductive

material inbetween materials that conduct heat easily.

Example, metal window frames conduct heat through to

the building, so plastic (polyamide) thermal breaks are

inserted. Photo sourced:

http://www.thermalheart.com.au/thermal-technology.php

- Double/triple glazing is the use of airspace inbetween two or three window frames to slow down heat transfer,

with the sealed air/argon gas sections stopping heat coming into and leaving the building.

-

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- Use of thermal mass, using the mass of the materials the builidng is constructed from to capture heat either the

heat or cold from the day, then to slowly release it into the building. This method is used best in climates that

differ from hot days to cold nights.

Arches, domes and shells.

Arches are curved structures used to span an

opening, and provide an alternative to traditional

beams. Arches can be built using masonry (stone), or

other materials (timber, steel, concrete). When

masonry arches are built they are made from wedge

shaped units, supported by a temporary wooden

structure called ‘falsework’, until the final central

piece, the ‘keystone’ is wedged into place,

redirecting the vertical force down through the sides

of the structure, through axial compression.

Due to the force being transferred out and down

walls underneath arches need to adequately built to

fight the forces. Buttresses, a diagonal bracing that

supports the arch bearing wall, could be used for

this. The blocks next to the wall in the image above are buttresses, though buttresses can come in different forms and

are sometimes decorated.

Right: A ‘flying buttress’ in Strassburg, sourced

http://keysersozeslair.com/?m=201111

Vaults are similar to arches, in the way that they are arched structures used to span distances. The difference between

arches and vaults is that vaults are further extended in the third dimension, and are used as ceilings and roofs, where

arches are used for window or door frames. Similar to

arches they may require buttresses to support the

weight.

Barrel vaults, used in corridors or halls, have a

semicircular cross section. (see right)

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Groin vaults are the join of two barrel vaults that run perpendicular to one another.

Right: Groin vault, Grand Mosque Abu Dhabi.

Sourced: http://dscwithlove.wordpress.com

A dome a structure that’s surface that is

shaped like the upper half of a sphere. It is

constructed of either blocks, a continuous

rigid material such as reinforced concrete, or

otherwise short linear elements – as

geodesic domes are (Ching, 2008).

Domes are similar to arches except the

circumferential forces acting are not

compressive the whole way down, they are

only compressive near the crown, and

tensile in the lower half. (Ching, 2008).

As seen in the diagram, hoop forces push outwards at the base of the dome, as so strengthening tension rings are put in

place to stop this bulge. This is turn compresses the top half of the dome, bring it back into a spherical shape.

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If the dome was made of concrete the bottom tension ring would be further reinforce to prevent bulging and potential

crown collapse.

Linear domes, made of either wood on metal, can take many different design, but utilise the structural security of the

triangle.

LINEAR STEEL DOME STRUCTURES

Scwedler domes: members follow longitiude/latitude,

strengthened by a set of diagonals (triangulating the

structure).

Lattice domes: Members follow circles of latitude, with

two different diagonally strengthening beams forming a

series of isosceles triangles. (Ching, 2008).

Geodesic domes are steel structures, where the members follow three

principle sets of great circles intersecting at 60ᵒ, subdividing the dome

surfaces into a series of equilateral spherical triangles. (Ching, 2008). The

difference between geodesic domes and lattice or Schwedler domes is

that at the crown a geodesic dome meets in pentagon, where the others

meet in a circle. This is because every lateral member meets in the same

spot on the lattice/Schwedler.

SHELLS

Shells a thin curved plate structures that are typically constructed from

reinforced concrete. Due to its thinness shells are not suited to carry

concentrated loads (Ching, 2008).

Example of a shell structure. Note that this too has a buttress style

reinforcing.

Source:

http://www.ketchum.org/shellpix.html

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Rubber and plastics

Rubber: Naturally sourced from tree sap, synthetic rubbers have a petrochemical origin.

The properties of rubber include being waterproof,

recyclability, ductility and flexibility, and are poor conductors

of electricity, which is why it is used as a protective and

insulating coating for electrical wires.

Common use of natural rubber includes flooring, gaskets,

seals, electrical insulation. Image sourced:

http://rubberpartsjakarta.com/?page_id=128

Common use of Synthetic rubber includes:

- EPDM: external rood lining, cold room doors, electrical insulation, is most

often used in car window seals. Source:

http://epdmrubber.wordpress.com/case-study-epdm-rubber-roof/

- Neoprene: flexible rubber used for wetsuits, orthopedic braces, electrical

insulation or mechanic fan belts.

Source:

http://imgau1.surfstitch.com/product_images/89407BLK-PATAGONIA-

1.JPG

- Silicone: used for sealants, cooking instruments, teeth impression

moulds (dentistry), plumbing.

Plastics:

Plastics are made by chemically mixing carbon, silicon, hydrogen, nitrogen,

oxygen and chloride to form monomers, then from monomers chains of

polymers.

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Properties of plastics depend on the specific type, majority are waterproof, therefore are non-permeable, plastic

does not conduct electricity. Other than when exposed to severe heat or weather, plastic will not shatter or break.

There are 3 main groups of plastics; thermoplastics, thermosetting plastics, and elastomers.

1. Thermoplastics: can be moulded when hot, and set again when they cool down. Thermoplastics are recyclable.

Examples of thermoplastics are PVC pipe (Polyvinyl chloride), Perspex, polyethylene and polycarbonate.

Polyethylene pool toy, source: www.alibaba.com

Polycarbonate sheeting,

sourced: http://www.livingspaceltd.co.uk/gallery/polycarbonate-sheet/

2. Thermosetting plastics: can only be shaped once. Examples include melanide formaldehyde (laminex) and

polystyrene. Laminex is used in benchtops, furniture. Polystyrene is used in disposable cups, plates, as well as

insulation panels.

3. Elastomers (synthetic rubbers). Includes EPDM, Neoprene and silicone. See rubber section.

Paints

Paints start off as a liquid, and solidify when applied on a surface and exposed to air. There are three components to any

paint, including the binder element, the diluent element and the pigment element.

- Binder: the part that makes the paint solidify. Example of binder element is polyurethane

- Diluent: dissolves the paint, and adjusts the ‘thickness’ of the paint. Eg. Thinners, alcohol, ketone

- Pigment: gives the colour to the paint. Can be either natural or synthetic

2 types of paints: Oil based and Water based

Oil based: has a high gloss finish, brushes need to be washed with turpentine as the paint is non soluble in water.

Water based: easier and safer to work with, can be rinsed out with water. More durable and flexible than oil based.

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Week 8

Key terms

Caulking: sealing something with silicone. Eg. Sealing around a window

Gasketing: sealing around something that allows for something to enter and withdraw.

Eg. The seal around a car window, that seals when the window enters it.

Window sash: The

operational part of the

window, the part that

slides up and down to let

air/heat in.

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Deflection: the degree to which something (an element) is displaced after being put under the weight of a load.

Moment of Inertia: distribution of weight from the

centre of an object. Eg. Rotating a pole when your hand is in the middle has a lower than when you rotate the pole

holding an end.

Door furniture: relates to anything attached to a door. Eg. Knobs, peepholes, knockers

Stress: Internal forces acting on neighbouring particles when an object is put under weight of a load. Eg. A beam is put

under a load, the particles within pull on each other to combat the strain

Shear force: forces within the material pushing it one way, against the other, causing it to break- similar to the action of

scissors.

Door leaf: the very top face of a door.

Curtain wall system: a wall system that is made entirely of windows.

What is glass?

Glass is a mixture of silica sand (heated to extreme temperature), + lime (used as a flux) + lime (used as a stabilizer).

Properties: Conductor of heat, resistant to electrical conductivity, close to fully transparent, chemical resistant, non-

porous, waterproof, recyclable

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3 major Types of flat glass:

Float glass- a molten ribbon of glass is poured over a layer of molten tin, then allowed to cool. No polishing/grinding is

needed

Plate glass- molten metal rolled into a sheet, cooled then ground and polished.

Sheet glass – made by drawing molten glass from a furnace (drawn glass), or by forming a cyclinder, dividing it

lengthwise and flattening it. (Ching, 2008).

Other types of glass:

Annealed glass: slowly cooled glass

Heat strengthened glass: heated then suddenly cooled for strength. Twice as strong as annealed glass

Tempered glass: annealed glass reheated to just below softening point then cooled. Has 3-5 times resistance to impact

than annealed glass, cannot be reshaped post-

fabrication. (Ching, 2008).

Image: sourced:

http://www.bharatsafety.com/tempered_glass.html

Laminated/safety glass: two sheets of flat glass bonded together around a

polyvinyl resin that prevents shattering when broken. Used in car windscreens.

Similar to wire glass: glass that is reinforced with a wire mesh inside the glass

material, to provide strength and non shattering properties.

Spandrel glass: opaque glass used to disguise structural elements curtain

walls.

Efficiency of a beam can be increased by making the span of the beam smaller,

or doubling the height of the beam. Halving the span of the beam/ doubling its

width reduces bending stress by a factor of 2, while doubling the depth

reduces bending stresses by a factor of 4. (Ching, 2008).

P a g e | 25

Types of windows:

The function of a

window is to allow

and disallow air, light,

and heat to enter a

building.

P a g e | 26

DOORS

TIMBER WALL SYSTEM

From quiz/modules:

1. Top plate, goes all way around

2. Head trimmer (doorway)

3. Stud

4. Lintel (in window)

5. Nogging

6. Jamb stud

7. Sill (in a doorway)

8. Sill trimmer (in window)

9. Bottom plate, goes all way around

Left: A sliding window

P a g e | 27

10. Stud

IN STUDIO

This week we were given a profile from the Oval Pavillion, and tasked with studying

the drawings to work out what our assigned area was, then walked to the Pavillion

to see in person what the drawing represented. After this we were to scale our

details from a 1:10 ratio to a 1:1, on a larger piece of paper using scaled rulers. My

area was a window sill detail at the back of the building, facing Ormond College.

This is the west facing side of the pavillion, facing away from the football ground.

The window itself was nearly the full height of the building, and was positioned at

the end of an internal walkway within the building, providing natural light for that

walkway. The window was double glazed, which provided thermal insulation and

resistance – meaning it keeps hot air in or hot air out, depending on the outside

temperature, noise reduction as well as security, as this is a secluded spot.

The window sill is protected by 6mm thick fabricated steel hood, which is angled

down to assist in drainage of collected condenstation on the window, to prevent

mould forming at the base. The sill hangs out past the supporting brick wall, and is

therefore a cantilever, and is supported by an interal RHS frame.

The window is fully caulked all way round, and includes a compulsory safety standard blue strip at eye level, (as seen

left) to prevent patrons of the building walking into it in confusion.

The task of expanding the 1:10 ratio detail to 1:1 was completed by measuring each length and multiplying the

number by 10. Eg. 30mm at 1:10 ration was 300mm at 1:1. This

exercise was blown up onto an A1 sized piece of paper, with

different materials marked by different sized fineliners. The finished

result was a life sized replica of the actual detail layed out in 2D on

the A1 paper, which was covered with annotated baking paper.

P a g e | 28

Week 9

Key terms:

Sandwich panel is a ready made cladding that consists of two metal plates, sandwiching a layer of insulation. Image

sourced: http://www.panandpro.org/home/our-products-2/. Sandwich panels are a very efficient use of materials,

forming a lightweight but efficient cladding product.

P a g e | 29

Bending is where a slender object has force applied to it and it distorts under this weight, in a perpendicular direction to

the way the object is facing.

Skirting is a wooden board covering the lowest section of an interior wall,

where the wall meets the floor. Skirting, or skirting boards, cover any gaps

left by the join. The height of skirting boards was once an indication of

private residence in public places, eg. Higher skirting boards at the

upstairs section of a pub. Skirting is also known as ‘baseboards’.

Image sourced: http://www.alliancewoodworking.com/baseboard-

installation/

A composite beam is a beam made out of composite materials, that is there is a mixture of materials that make up the

same beam. An example of a composite beam is the wood and galvanised steel truss.

A Shadow line joint is a joint that allows

for movement and expansion, but is also

used for an aesthetic appearance.

Shadow line joints are where the

materials are butted up against each

other, but there is a small but visible gap

around each element, making each

individual element stand out. This is seen

as a very modern look, and is now very

common practice. Shadow line joints are

also sometimes known as ‘express

joints’. Image sourced:

http://culburrahemphouse.blogspot.com.au/2013_03_01_archive.html

A Cornice is a decorative trimming that runs around the upper wall of

a room. A cornice covers the join between the wall and the ceiling,

and is commonly decorated for aesthetic appeal. Image sourced: http://www.jadenmouldings.com.au/store/viewItem.asp?idProduct=41

Effects of stress on structural members:

P a g e | 30

Columns are effected by axial compression

differently depending on their shape. Shorter

and thicker columns are more likely to ‘crush’,

where longer and thinner columns tend to

buckle under stress.

For only compressive forces to be present

through a column all force must pass through

the exact middle point, the kern area, and if this

does not happen and the weight is applied

slightly to one side there will be forces of

tension acting upon the opposite side.

3 main movement joins

1. Expansion joints are ‘continuous unobstructed slots constructed between two parts of a building or structure,

permitting thermal or moisture expansion to occur without damaging either part’ – Ching, (2008). The gap left

by expansion joints is filled with a polyurethane sealant. Expansion

joints (vertical) are used in structural load bearing walls, and horizontal

expansion joints are only used in brick veneer walls. The backing rod

represented in this image is made from a tougher form of

polyurethane. Image source:

http://faculty.arch.usyd.edu.au/pcbw/walls/control-joints/index.html

2. Control joints are ‘continuous grooves or separations

formed in concrete ground slabs and concrete masonry

walls to form a plane of weakness, used to prevent and

regulate cracking due to shrinkage – drying, thermal mass

or structural movement can happen between each

individual element. Ching (2008). Control joints are just a

slot cut into the top of slab, made by a guided hand tool.

Image sourced: http://inspectapedia.com/structure/Concrete_Control_Joint065-DFs.jpg

P a g e | 31

3. Isolation joints divide up a larger or strangely shaped structure

into smaller, manageable sections so that movement can move

between each element. An example of isolation join is in a large

concrete slab, where the slab is split up into smaller sub-slabs

that have a small filled gap separating them. Isolation joints are

rarely needed inside, as the slab will not expand as much as one

on a roof, or any in the weather. Image sourced:

http://www.concretenetwork.com/concrete-joints/isolation-

joints.html

Composite materials

Materials are classified into either monolithic or composite materials. Monolithic materials are either a single

material, or a combination of two materials that are indistinguishable after being joined, for example a metal alloy.

Composite materials are a mix of two or more materials that are bonded together to form a product, but are still

separately distinguishable. 5 examples of composite materials include:

1. Fibre reinforced cement (FRC)

This reasonably inexpensive fireproof and waterproof

product is made from cellulose fibres, Portland cement,

sand + water, and is commonly used as an exterior

cladding. Common forms include sheet/broad products,

or shaped into pipes or tiles. In this image the FRC is

being used as a cladding in a sandwich panel, with two

FRC sheets sandwiching a polystyrene filling. Image

sourced:

http://wallking.en.alibaba.com/product/627438346-

210222935/Fiber_Reinforced_Cement_Panel_with_Polystyrene_Foam_Concrete_Filling_Strips.html

2. Fibreglass

This lightweight and strong, fire and waterproof product is

made from a mixture of glass fibre, epoxy resins and glass.

Fibreglass is commonly used as transparent wall and roof

cladding, as well as preformed products such as swimming

pools. The common form held by fibreglass is generally a flat

or profiled sheet, as well as formed or shaped products.

Image sourced:

http://www.diypoolsaustralia.com.au/above-ground.html

P a g e | 32

3. Aluminium sheet composites

This product is made from aluminium and plastic,

taking the form of a sandwich panel – with a phenolic

resin honeycomb core sheet, clad with two thin

external aluminium sheets. This forms a product that

can be used as an internal and external cladding

material. Benefits of aluminium sheet composites is

that there is less aluminum used, the panels are

lightweight, weather resistant, and provide the

opportunity for any finishes. Image source:

http://www.aluminum-honeycomb-panel.com/fiberlass-honeycomb-panel.html

4. Timber composites

Are made from solid timber, engineered timber and galvanised presses steel. The common forms timber

composites are found in trusses -

include the top/bottom chords with

galvanised steel or engineered

board/plywood webs. Benefits of

using timber composites include

minimum material use and maximum

efficiency, and the material is cheap

and reasonably sustainable.

5. Fibre reinforced polymers

Are made from polymers (plastics), timber, glass or carbon fibres. Forms of this product include moulded or

pultruded into shape (all used fibres are

pulled through a binding machine that

applies heat, pressure and resin to create the

new composite material). Fibre reinforced is

used for decking, external cladding for

buildings as it is resistant to corrosion and

has a higher strength to weigh ratio that steel.

Image sourced:

P a g e | 33

http://www.theengineer.co.uk/channels/production-engineering/in-depth/bristol-uni-pioneers-composite-

bridge-technique/1008752.article

IN STUDIO (was continually denied access to hotbox,

due to an ‘unknown error’).

There is a four tower complex being built in the city,

mainly being built out of reinforced concrete. Although

two have been finished, the third and fourth towers are

being built now. This concrete they are mainly built

from is reinforced with hot rolled steel circular bars,

which strengthens the concrete and allows it to span

longer distances and to carry heavier loads. As the

building is moving up layers, it is constantly being

propped up to support is continually growing weight,

hence when we where there we observed layers and

layers of propping, even 3 floors underneath where the

newest layer was being poured. (As represented in this

sketch).

Week 10

Key terms

A Shear wall is a wall used to stiffen a building against lateral

loads, by transferring lateral loads into vertical loads. Shear

P a g e | 34

walls act a cantilever running perpendicular to the ground, using both compressive and tensile forces to rigidify the

building. Also the weight of a shear wall can significantly help resisting overturning forces.

If a building only has a shear wall at only one the unsupported end will be nowhere near as secure, and hence when

the lateral forces (wind) are applied to the building the unsupported end will sway a lot more than the shear walled

end, and this will cause a damaging twist in the middle of the building. This could be fixed by making the building

more symmetrical, by installing a matching shear wall in the other end of the building.

A soft story occurs when a level within a building is less stiff/more

flexible than those above or below it. An example of a soft story would be an

open to public ground level foyer to a building, with glass windows

wrapping around the whole building. If this layer relied just on columns to

support the weight of the building above, and did not have diagonal

bracing to provide lateral support, when lateral forces were applied its

construction could result in non-uniform deflection, which could cause

that floor to fail, potentially bringing down the whole building. Pictured is an

example of a soft story failing under lateral loads, leading to the collapse of

a building. Image sourced: http://www.air-

worldwide.com/Publications/AIR-Currents/Izmit-D%CF%8Bzce-Ten-Years-

Later--Is-Istanbul-at-Greater-Risk-Today-/

Braced frame relates to a framing system that has been adequately

braced in both lateral and longitudinal planes, that is vertically and

horizontally. Depending on the forces being applied to the

structure one brace may be in tension and the other slack, or in

compression, or vice versa. Overall, bracing a frame allows the

structure to move less, but move as a whole rather than certain

sections more so than others. Bracing comes in many forms, but the

most common and simple is the

Lifecycle relates to how many applications a material can have

over its lifetime. For example rock can be sourced from a quarry,

crushed and made into a concrete block. After this concrete block

has been used in wall for many years the wall is demolished, the

block crushed and the rock now is used as filings above an AGI pipe. This cycle, this story of the material changing for

and use is what a lifecycle is.

A defect is a characteristic obstructs a material or products

safely fulfilling its purpose, or being structural sound.

Something may have a defect in certain measures were not

taken during a construction stage or the material itself does

not reach a certain safety standard, and will not be safe to

be used until this defect is fixed, or replaced. Defects in a

construction sense can relate to building methods not

being fully completed or something within the building

P a g e | 35

being broken, and not doing its job. The rot in the roof rafter in this photo shows a defect, that should be replaced

or fixed immediately, as the roof is at risk of collapsing at this point in due time. Image sourced:

http://www.truelocal.com.au/business/safehome-building-inspections/southbank

A fascia is a horizontal board situated just below the level of roof, that covers the end of rafters. A fascia is

sometimes used to mount a gutter system, as it is positioned in the perfect spot to catch the water collected by the

roof. A fascia can be made from either timber or metal, and it is a non structural element.

Corrosion relates to the degradation of material, by either oxidization or by chemical reaction and molecular change

(through ionic exchange). Oxidisation is the interaction of water molecules and oxygen and unprotected iron

molecules, which slowly over time react to one another to form an iron oxide (rust). This can be prevented by

galvanising (hot dipping in zinc to give steel a protective coating). Oxidisation is the reason that copper gradually

turns green over time, it is exposure to oxygen and the reaction between the copper and the oxygen. Corrosion can

also happen when different metals come into contact with one another. When a metal with extra electrons is in

contact with another metal that is looking for extra electrons, ionic exchange will happen and the degredation of the

metal (giving away electrons) will begin. The likelihood of corrosion between metals can be gauged by using this

scale. A basic rule of thumb related to this is ‘if it’s at the top of the scale,

it is ok to be put on top of a building (in a stable, non-salty environment).

That is, a material at the top of the scale is not giving away electrons, so

ionic exchange will not happen. If its vice versa, then corrosion will

happen. If the building is a salty environment it is best to not mix metals,

but to use a combination of wooden cladding and uniform metal

cladding.

IEQ expands to ‘Indoor environment quality’. This relates to how

comfortable the indoor environment is to its patrons. If there is bad

things like VOC’s (volatile organic compounds) such as oil based paint

(which realizes toxic fumes leading to patrons having headaches, the IEQ

isn’t very good, as it is harming users. Ways to get around this decreased

IEQ is to choose and purchased already finished products and material for

the building, so there will never be fumes trapped inside the building.

Wind forces are a function of the size of the

exposed surface area of a structure. Effects of

wind come from a horizontal direction,

applying positive pressure to wall and roof

facing the direction of the wind, provided the

P a g e | 36

angle of the roof is greater than 30ᵒ. When the angle of the roof is less than 30ᵒ the wind exerts negative

pressure/suction on the sides and leeward surfaces (surfaces facing into the wind) and normal to the windward roof

surfaces. Ching (2008).

These two digrams display the effect that wind has on a structure. The roof on the left is greater than 30ᵒ, if it was

less than the wall both the side walls (one on far right, and hidden one on far left) would be sucked in by the

negative pressure.

As buildings are generally designed to carry vertical loads, it is horizontal, or lateral loads that must be braced for

when designing to withstand earthquakes. Lateral bracing at the bottom of a building to try to secure the weight at

the top of building is a tactic used to defy earthquake forces. Allowing the building to move as one whole unit can

help the building survive. Bracing, shear walls and rigid joints hold the building together when faced with seismic

forces. Isolators made from rubber based in the foundations of a building in an earthquake prone area is a tactic to

remove the bulk of the forces before they even get into the building structure. Image sourced:

http://www.pbs.org/wgbh/nova/next/tech/rubber-bearings-seismic-protection/

3 key strategies for lateral support

1. Bracing

2. Shear Wall diaphragms

3. Moment resisting wall

1. Bracing resists horizontal forces, and can be applied to walls. Images sourced:

https://www.dlsweb.rmit.edu.au/toolbox/buildright/content/bcgbc4010a/04_struct_members/03_wind_bracin

g/page_001.htm

P a g e | 37

2. Shear wall (see key terms) and

Diaphragms. Diaphragms are

structural elements that collect

lateral forces in the horizontal plane

and transfer them to the supporting

vertical columns, so the whole

building moves as a unit. An

example of a diaphragm is a

concrete floor slab, or a flat roof.

3. Moment resisting frames are

structural joins between horizontal

concrete slabs and vertical

columns, meaning the whole

building moves a monolithic

unit. In this photo the

reinforcement extending from

the columns is waiting to be

linked to reinforcement in the

soon to be built floor slab,

when this is completed there

will be a moment revisiting

frame formed by the

connection of slab to column.

Image sourced:

http://www.constructionphotography.com/Details.aspx?ID=15059&TypeID=1

P a g e | 38

In studio:

The three waterproofing tactic used in the photo are 1.

An angled drainage route, this collects any water that

has run down the window and distributes it into the

garden below, keeping it away from the building and

watering the plants at the same time. The second

waterproofing method is caulking, applying a

polyurethane sealant along the edges of the window to

prevent any water getting in where the window meets

the wall, or the bespoke metal hood in this case. The

third waterproofing method is the same as the second

(caulking), but is applied between the brick wall and the

metal hood. This kind of waterproofing, as both of these

materials (brick and steel) will expand, and the flexible

polyurethane sealant allows room for this movement,

all the while remaining watertight.

The second image shows a close up of caulking at the

bottom and sides of the window. And the bend in the

metal hood is either a fold in the material, or a finished

grinded and treated weld – neither of which should

have any holes to allow water in.

1.

2.

3.

P a g e | 39

The caulking method of waterproofing is very reasonable, as it is easily applied, and effective. The hood should have a

drip system underneath (positioned above the garden) to prevent water running back to the wall using surface tension.

Other than that the use of steel is effective as it is waterproof itself, and long-lasting when treated with suitable

finishing, which in this case it has been. The paint on the metal hood is a gritty waterproof paint, as so it further

contributes to the waterproof nature of the whole structure.