Constructing Environment Log Book Chan Cheung Fung Ian 692233
Week 3 E-learnings The design of a structural element is based on the loads to be carried, the material used and the form and shape chosen for the element. The elements from which a structure is made or assembled have, in engineering or building terms, specific names which are used for convenience
a slender element design to carry load parallel to its long axis. The load produces compression Strut Structural elements Beam Generally a horizontal element designed to carry vertical load using its bending resistance
a slender element design to carry load parallel to its long axis. The load produces tension Tie Slap/Plate
a wide horizontal element designed to carry vertical load in bending usually supported by beams Panel a deep vertical element designed to carry vertical or horizontal load
Week 3 E-learnings Foundations are found at the bottom of buildings where the building meets the ground. The foundations are the substructure of the building and their function is to safely transfer all loads acting on the building structure to the ground.Where parts of the substructure are located below the ground, the foundations must also be able to resist the force of the soil which is pressing against the foundation walls, or retaining walls. Buildings compress the earth beneath them and the buildings tend to sink a little into the ground overtime. Also, footings and foundations should be designed to ensure that this settlement occurs evenly and that bearing capacity of the soil isn’t exceeded. Cracking in a building often occurs with differential settlement which means settlement that is uneven
Settlements are used where soil conditions are unstable or where the soil bearing capacity is inadequate. The load is transferred from the foundations, by the unsuitable soil and all the ways down to levels where bed rock, stiff clay, dense sand or gravel is located
rely on the resistance of the surrounding earth to support the structure Friction Piles Footings and Foundations
Deep Foundations Strip Footings
used when loads from a wall or series of columns is spread in a linear manner
End Bearing Piles extend the foundations down to rock or soil that will provide support for the building loads
are used where soil conditions are stable and where the required soil bearing capacity is adequate close to the surface. The load is transferred vertically from the foundation
Shallow Footings Pad Footings It is also named isolated footings. This type of footing helps to spread a point load over a wider area of ground
Raft Foundations sometimes also called a raft slab, this type of foundation provides increased stability by joining the individual strips together as a single mat
Week 3 E-learnings
Extruded and wire-cut
Machine pressed Types
Bricks
Handmade
A standard concrete block is standard size masonry unit made out of concrete. There is a large range of sizes and proportions available in orider to suit different purposes. They are manufactured from cement, sand, gravel and water. The manufacture process involves mixing, moulding and curling. They are mainly used in the construction of walls both load bearing and non-load bearing, to provide greater structural resistance to lateral loads, concrete masonry units are often strengthened with steel reinforcing bars and then filled with grout
Concrete Block
Different Materials used in construction
Stone Igneous Sedimentary stone It is formed when molten rock cools down
limestone, sandstone. It is formed when accumulated particles are subjected to moderate pressure
Metamorphic marble, state. It is formed when the structure of igneous or sedimentary stone changes when subjected to pressure, high temperatures or Chemical process
Week 3 Class Activities In this week we went for a tour around the school looking at different buildings and their structures
indicated in the sketch below
The picture below is showing the one of the support in the underground car park below South Lawn In the pictures we can see the beams there which are black in color. However these are pretty special beams. As beams are suppose to have vertical load coming from above. As
The design of this support is pretty interesting as there is a tree inside it
There are quit a lot of these supports in the car park, which they can act as drains for the South Lawn and the support of the car park at the same time Another design that can act as a drain as well outside of Union House
Week 4 E-learnings
Span
the distance measured between two structural supports
Can be measured between vertical supports (for a horizontal member) or between horizontal supports (for a vertical member)
is not necessarily the same as the length of a member
Spacing of the supporting elements depends on the Spanning capabilities of the supported elements
Week 4 E-learnings sometimes combine with concrete slab systems to where the particular benefits of steel framing and shallow depth floor slab systems are desired. The spanning capabilities of the particular materials help to determine the spacing requirements of the supports In many instances a combination of member types and materials are combined (e.g. heavy and light members) depending on their structural function
Framing Systems
Traditional Timer Floor Framing systems use a combination of Bearers (Primary Beams) and Joists (secondary beams) The span of the bearers determines the spacing of the piers or stumps and the spacing of the bearers equals the span of the joists
Timber Systems Different Systems
Concrete Systems Slabs of various types are used to span between structural supports. These can be one-way or twoway spans
Steel Systems Steel Framing systems take various forms, with some utilizing heavy gauge Structural Steel members and others using Light Gauge steel framing. Steel Framing systems sometimes combine with concrete slab systems to where the particular benefits of steel framing and shallow depth floor slab systems are desired. The spanning capabilities of the particular materials help to determine the spacing requirements of the supports In many instances a combination of member types and materials are combined (e.g. heavy and light members) depending on their structural function
Week 4 E-learnings
Concrete components Provenance When the cement powder and water are mixed, a chemical reaction takes place and heat is released. This process is called hydration. During this process crystals are formed that interlock and bind the sand, crushed rock and cement/water paste together. If too much water is added, the concrete mixture will be too stiff and it will be very difficult to work with (unworkable)
Process
Formwork
One of the great advantages of concrete is that it is fluid and shapeless before it hardens. It can be formed into any shape we desire
is the term used for the temporary support or moulds used to hold the liquid concrete in place until it becomes hard Formwork can be built at the building site – IN SITU – or in a factory – PRE CAST – out of a range of different materials – timber, metal, plastic, formply etc.
Reinforcement
Process During the curing process the formwork needs to be supported as the weight of the wet concrete is very heavy. This is achieved by using props and bracings of various types Concrete generally reaches 75% of its compressive strength in approximately 7 days with testing for the required strength occurring at 28 days Once the concrete is hardened and strong enough, the formwork is carefully removed. Formwork is often removed, stored and reused or it may stay in place forever (sacrificial formwork)
Concrete is also known as “artificial stone”. This suggests that the properties of concrete and stone are similar. Concrete is very strong in compression but is weak in tension. To improve its structural performance, steel (very strong in tension) reinforcement in the form of Mesh or Bars is added. The result material is what we know as reinforced concrete.
generally cost effective. Labor dependent for formwork & Pouring
Week 4 E-learnings
high embodied energy, Nonrenewable. Long lasting
Cost- generally Sustainability & cost effective, typically very Carbon Footprint Labor durable High . Can be Durability/Life span scratched with a low. Can be Chipped metallic object Fragility with a hammer Hardness
Properties of Concrete
Ductility very low ductility Reusability Medium-Low. Can be partially re0used when crushed to be used as aggregate for new concrete elements
Porosity/perme ability
Conductivity
Poor conductor of heat and electricity
Flexibility/plasticity
medium – low, depending on proportions and components (aerated or high water ratio concrete has a high porosity vs waterproof concrete that is created when permeability reducing admixtures are included in the concrete mix
low flexibility and plasticity Density Medium – High. Approximately 2.5 More dense than water
Week 4 E-learnings
Concrete- considerations 1. Concrete is permeable (not completely waterproof). This is one of the main sources of problems in concrete. If the steel bars are too close to the surface they will not be protected from moisture and oxidation. This will cause both aesthetic and structural degradation of the concrete. 2. Another common cause of problems is poor vibration of the concrete during the pouring process. Concrete is vibrated to get rid of the air bubbles that get caught during the pouring process. These bubbles can compromise the structural performance of the element and, in a worst case scenario, result in the element failing. Floor and Wall systems A BEAM can be: - supported at both ends of the beam - supported at numerous points along the length of beam - supported at points away from the ends of the beam (creating overhangs / cantilevers beyond the supports) - supported at only one end of the beam (these beams are called cantilevers) A CANTILEVER can be: - horizontal - vertical - angled
Week 4 E-learnings
Types of Joints 1. Construction joints- used to divide the construction into smaller and more manageable sections of work 2. Control joints- required to absorb the expansions and contractions that thermal variations cause and the long term tendency of concrete to shrink over time. The elongation/shrinkage is proportional to the temperature differential. The material coefficient and the dimensions of the piece. 3. Structural joints – the type and performance of the structural connections joining the precast elements to each other and to other parts of the structure are critical for the overall performance of the building
Week 4 Class Activity In this week’s studio, we start to look at drawings of roofs in order to get prepared for the roof model making for the next week
The drawing above is showing the roof model we are going to make in the following week. As we look at the drawing, we can identify some structures mentioned in the e-learnings and text book. On the left of the drawing, there is obviously a stud (support) to keep the roof from collapsing, and a beam to
keep everything together. A sketch of the stud and beam is shown below
Also, when we look at the trapezium shaped roof, we can see the trussed roof structure which is making the roof more stable. A sketch of the trussed roof is shown below
When we look at the bottom part of the drawing, we can see the main support holding up the roof from collapsing. The trapezium shaped support is consist of several bracings, making it to become a more stable support. A sketch of the trapezium shaped support with bracings is shown below
Week 4 Work shop In the week before, I went to the work shop which is related to beams. In the workshop, we divided into four groups, each group have to make a beam. First, we get to choose materials.
The photo above is showing the materials that we have chosen. Which are three long and thick wood and two thin wooden board. What we have decided to do was nailing those three pieces of long thick wood on top of each other and nail the two thin wooden boards on one side. We predict using this
design for a beam can afford the most load. These photos show the finishing products of our group and three other groups respectively
Later on, we tested on the four beams and see which one can take up the most load. The test was to apply load from above the beam, the sketch on the right indicates how the load is flowing from above
Week 4 Work shop
At the end, our group won because the beam we created can take up the most load, which was 480 kg and it can be bent up to 60 mm before it breaks. Unfortunately my camera’s battery was flat so I do not have a photo of our beam after it broke. But those beams looked pretty much the same when they broke. The photos below shows the look of the beams from the other groups after they broke from overloading
Beam from group 1 Load:370 kg Bending: 32mm
Week 5 E-learnings
Columns: are vertical structural members designed to transfer axial compressive loads. All columns are considered slender members and for axial loads, they can be classified as either the short or long become shorter when a compressive load is applied and then failed by CRUSHING when the compressive strength is exceed
Short columns Short and Long Columns are shorter (length) and thicker (cross-section). Columns are considered short if the ratio of effective column length to the smallest cross section dimension is less than 12:1. They will be structurally adequate if the load applied to the column cross section does not exceed the compressive strength of the material. Compressive Strength (Pa) = Load (N) / area (mm2)
Long Columns are taller (length) and slimmer (crosssection). They are considered long if the ratio of effective column length tot the smallest cross section dimension is greater than 12:1
become unstable and fail by BUCKLING. The actual length of long columns and how they are fixed at the top and bottom of the columns determines how they will buckle and how much load the column can carry
Week 5 E-learnings
Walls made the main structural part of a building. Wall systems Concrete frames typically use a gird of columns with concrete beams connecting the columns together
Concrete frames
Reinforced Masonry
Structural Frames Steel frames Steel frames typically use grid of steel columns connected to steel girders and beams
Load Bearing Walls – Concrete, masonry
load bearing walls can be constructed from core filled hollow concrete blocks or grout filled cavity masonry. Bond Beams over openings can be created using special concrete blocks which are filled with concrete to bond the individual units together. After the concrete has cured, the temporary propping can be removed, leaving only the appearance of the concrete block wall. Bond beams are used as an alternative to steel or concrete Lintels
Walls, Grids and Columns Timber frames
Solid Masonry Cavity Masonry
Timber frame typically use a grid of timber posts or poles connected to timber beams. Bracing of members between bays or at the corners of post/beam junction is required to stabilize the structure walls are typically formed from two skins of masonry. It has better thermal performance and opportunities for insulation within the cavity, better waterproofing and the opportunity to run service within the wall cavity
load bearing walls can be created with single or multiple skins of concrete masonry units or clay bricks. The skins of masonry are joined together using a brick or with metal wall ties placed within the mortar bed
Stud Walls
Metal and Time stud framed walls Brick veneer construction
Concrete load bearing walls can be achieved using either is situ or precast elements. The load bearing panels may also provide support for spandrel panels over and link into other structural elements
Light gauge steel framing, timber framing
use smaller sections of framing timber or light gauge framing steel to meet the structural demands of the construction
is a combination of 1 skin of non-structural masonry and 1 skin of structural frame wall are widely used in the construction industry
Week 5 E-learnings
From Wood to Timber Early wood is rapidly growing at beginning of growing season thin, large cells – lighter color. Late wood is growing slower, often limited by lack of water thick small cells – darker color. Growth is generally one ring per year / some climates may have more than one growth season per year / fires or disease may produce an extra ring Why is timber seasoned? It is to adjust the moisture content so the timber is appropriate for the intended use. It is to provide increased dimensional stability. What moisture is removed from the wood? They are free moisture and bound moisture. How is the moisture removed? Timber is generally seasoned in one of three ways. Air seasoning – Cheap but slow about 6 months to 2 years per 50mm thickness. Kiln seasoning – Typically 20 – 40 hours to dry to about 12% Solar kiln seasoning – Less expensive to run
Week 5 E-learnings
Different woods have different properties Woods
Hardwoods In Australia common softwoods include all conifer species of radiate pine, cypress pine, hoop pine and douglas flir
Softwoods Native Australian hardwoods include all eucalyptus species of Victorian ash, brown box, spotted gum, jarrah, Tasmanian ook and balsa wood
Week 5 E-learnings
Quarter Swan
Growth rings parallel to short edge
Advantages
best grain shows on face, good wearing surface for floors & furniture, radial face preferred for coatings, lower width shrinkage on drying, less cupping and warp than other cuts and they can be successfully reconditioned
Disadvantages
slower seasoning and nailing on face is more prone to splitting
Week 5 E-learnings
Back Swan
Growth rings parallel to long edge
Advantages
season more rapidly, less prone to splitting when nailing, wide sections possible and few knots on edge
Disadvantages
shrink more across width when drying, more likely to wrap and cup and collapsed timber more difficult to recondition
Week 5 E-learnings
Radial Swan Face is always a radial cut
Advantages
Dimensional stability, less prone to warping & cupping and less wastage in milling
Disadvantages
Wedge shaped cross section, more difficult to detail and more difficult to stack
Week 5 E-learnings
Timber Properties The hardness medium is medium to low as most timbers can be reasonable easily marked. The fragility is medium to low as timber is geometry dependent, generally it will not shatter or break. The ductility is low but some timbers in their green state can be manipulated into a range of shapes. The flexibility is high and medium plasticity. The porosity is high, it varies depending on seasoning, finishing and fixing. The density is extremely carried depending on timber type. The durability can be very durable as it varies depending on type, seasoning, finishing and also fixing. The recyclability is very high as second hand timber is also very desirable. The cost is generally cost effective. The labour dependent for on-site work but also suited to highly efficient factory based manufacturing processes
Week 5 E-learnings
Timber – Specifying and Handling Design detailing can and should be minimize exposure to hazards. Always specify timber for a particular use Depth x breadth, make sure size is available before specifying and length
Repellent treatments will be required Treatment
Seasoned < 15%, any timber >15% is sold as unseasoned
Moisture Content
Size
Timber Strength Grade F-graded & MGP grading are commonly used to identify the strength of particular timber elements
Species of wood
Availability Not all timber types or sizes are available in all locations
Different timber types provide variations in performance and appearance
Week 5 E-learnings
made by layering hardwood or softwood residuals in specific orientations with wax and a resin binder by applying high temperature and pressure. Uses – as part of structural systems / cladding finish timber/LVL flanges, two Chipboard & Strand Board Beams plywood/OSB webs, suitable for larger spans, Timber Flanged Steel Box Beams torsional stiff and can Web Joists use decorative plywood. Engineered Timber Uses – floor joists / lightweight, open webs give access LVL rafters. Glulam for service webs by light tubes, solid rounds, corrugated sheets. made from gluing laminated veneer lumber, Uses – floor joists / rafters pieces of dressed made from laminating thin sawn timber sheets of timber, most MDF together to form a laminates with grain dinged to Plywood deep member, most longitudinal direction, very Medium Density Fiberboard, made made by gluing and pressing by breaking down hardwood or think laminates together to laminates with grain deep and long sections softwood waste into wood fibres, form a sheet, grain in combining it with wax and a resin laminates in alternate dinged to possible and high strength. directions, strength in two binder by applying high longitudinal Uses – mainly structural temperature and pressure. MDF is directions. Uses – structural bracing/ flooring/ generally more dense than direction. Uses – formworks/ joinery/ marine plywood. Uses – non-structural applications applications mainly structural
Week 5 Class Activity In this weeks studio, we got our materials with us which are: thin wooden sticks, glue and cutters. We were ready to start building the roof model which we have already looked at in advance in the week before
The photos above show that we are measuring the length of each part from the drawing of the roof. Then we cut the thin wooden sticks into certain lengths according to the scale of the drawing. The scale was 1:20.
We worked towards the end of the studio. But unfortunately we not have enough time to finish the roof. Such as we did not finish the main support with bracings.
This is probably the reason why the roof could not stand up as the main support is not finished. However, there are still some parts we have finished in the studio such as the stud supporting the roof at the front.
A sketch of the finished trussed roof, the beam and the stud is shown below
The photo below shows the progress of our roof model making when the studio finishes
Week 6 E-learnings
The top surface is sloped towards drainage points and the entire roof surface finished with applied waterproof membrane
Are generally flat plates of reinforced concrete (or precast slabs with a topping of concrete) Concrete Roofs
Flat structural steel roofs consist of a combination of primary and secondary roof beams for heavier roof finished such as metal roofing
Structural steel framed roofs
Roofs Trusses are manufactured from steel or timber components, fixed together to form efficient elements able to span long distances
Trussed roofs Truss roofs are framed roofs constructed from a series of Open Web type steel or timber elements
The shape (slope) and material of the structural elements is often determined by the roofing material selected and the functional requirements of the roof
consist of roof beams and purlins and lighter sheet metal roofing. Portal frames consist of a series of braced Rigid frames (two columns and a beam) with Purlins for the roof and Girts for the walls. The walls and roof are usually finished with sheet metal
Week 6 E-learnings
Space Frames Space frames are 3D Plate type structures that are long spanning in two directions Linear steel sections of various cross sections types are welded, bolted or threaded together to form matrix-like structures are characterized by a vertical, triangular section of wall at one or both ends of the roof The roof consists of Common Rafters, Ridge Beams and Ceiling Joists. Where the roof overhangs the gable end wall Outriggers are used
timber, cold-formed steel sections (and also sometimes heavier steel (UB or PFC) for major beams) Materials HUP Roofs
Gable Roofs
Light Framed Roofs Materials timber, cold-formed steel sections
are characterized by a vertical, triangular section of wall at one or both ends of the roof consists of Common Rafters, HIP Rafters, Valley Rafters, Jack Rafters, Ridge Beams and Ceiling Joists
Week 6 E-learnings
Metals- Provenance
Types: 1. Iron is the 4th most common element in the Earth (cheap) 2. Non-Iron – all other metals – generally more expensive (less common), less likely to react with oxygen (to oxide) and superior working qualities 3. Alloys – combinations of two or more metals Metal- properties – can greatly differ depending on type 1. Hardness – varied. Depending on type 2. Fragility – low. Generally will not shatter or break 3. Ductility – high 4. Flexibility/plasticity – medium – high flexibility and high plasticity (while heated) 5. Porosity/permeability – generally impermeable – used for guttering, flashing etc 6. Density – high 7. Conductivity – Very good conductors of heat and electricity. This can be an advantage or disadvantage depending on the location and purpose of the metal 8. Durability/life span – can very durable.Varies depending on type treatment, finishing and fixing 9. Reusability/recyclability – high 10.Sustainability & carbon footprint – very high embodied energy. Recyclable and renewable if correctly managed 11. Cost – generally cost effective (can be very material-efficient and an economic option)
Week 6 E-learnings
Metal â&#x20AC;&#x201C; considerations 1. Metals will react with metal by giving up/taking on another metalâ&#x20AC;&#x2122;s ions. 2.The Galvanic series (shown below) lists the metals in order of their tendency to give up ions to other metals and corrodes 3.Ion transfer will happen when the metals are directly in contact with each other or they are in an environment (water/moisture) that facilities the transmission of the ions 4.Be aware that different metals in direct contact or in an electrolyte will corrode. To reduce the risk of corrosion metals can be separated by an insulator such as a rubber gasket or kept away from sitting in moisture 5. Some metals cause steel to corrode whereas other metals corrode deferentially themselves thereby protecting the steel, Galvanized steel is steel coated by a thin layer of zinc to protect the steel from rusting 6.Water related damage 7.Oxidation and corrosion, metal ions can react with oxygen forming an oxide which can sometimes protects the metal but in other instances it can result in the corrosion of the metal. Aluminium oxidises to form a protective layer. Rusty steel is an example of undesirable corrosion 8. Protect against water to reduce corrosion 10. Avoid prolonged exposure to moisture 11. Seal against moisture 12. Chemical treatment
Week 6 E-learnings
Steel properties 1.Very strong and resistant to fracture 2. Transfers heat and electricity 3. Can be formed into many different shapes 4. Long lasting and resistant to wear Steel
Stainless steel alloys -chromium is the main alloying element -the alloy is milled into coils, sheets, plates, bars, wire and tubing. Generally used harsh environments or where specific inert finishes are required. Wall ties in cavity walls are often made from stainless steel due to its corrosion resistance -stainless steel is very, very rarely used as primary structure due to cost
Steel sheeting
Structural steel Framing – columns, beams, purlins, stud frames. We will refer to different steel sections or profiles depending on the shape of the structural element. There are two main types
Hot rolled steel elements are shaped while metal is hot. More material is required for this type of process. Generally used as primary structural elements – often protected from rusting and corroding by coatings – joints are welded or bolted
Cold formed steel
Cladding and roofing must be protected from weather exposure
elements are folded from sheets that have been previously produced and cooled down. Used as secondary structure – protected by hot dip processes – joints are bolted or screwed Reinforcing bars – due to its good tensile resistance, steel is used in conjunction with concrete to produce reinforced concrete. Deformations on the bars assist bonding with the concrete
Week 6 E-learnings
Aluminium â&#x20AC;&#x201C; Distinctive properties 1.Very light compared to other metals 2.Non-magnetic and non-sparking 3. Easily formed, machined and cast 4.Pure aluminium is soft and lacks strength, but alloys with small amounts of copper, magnesium, silicon, manganese and other elements have very useful properties Aluminium- uses 1. Extruded sections are common for window frames and other glazed structures such as balustrades/ handrails 2. Cast door handles and catches for windows 3. Rolled aluminium is used for cladding panels, heating and air-conditioning systems 4. Aluminium reactions with air creating a very fine layer of oxide that keeps it from further oxidation giving it that matte natural finish 5. Other finish treatments can also be applied. The most common treatments are Power Coating and Anodisation
Week 6 E-learnings
Copper properties 1.Copper is a reddish with a bright metallic lustre when polished and turns green when exposed to the weather for a prolonged time (oxidation) 2.Very malleable and ductile 3. Good conductor of heat and electricity Copper uses 3. Traditionally used as roofing material, natural weathering causes to develops a green coloured patina over time 4. It is also widely used for hot and cold domestic water and heating pipework 5.Electrical cabling
Week 6 E-learnings
Zinc properties Zinc is a bluish-white, lustrous metal. It is brittle at ambient temperatures but is malleable at 100 to 150oc. It is a reasonable conductor of electricity Zinc Uses Plating thin layers of zinc onto iron or steel is known as galvanizing and helps to protect the iron from corrosion. This is particularly useful in the protection of roofing material
Week 6 E-learnings
Lead properties Lead is a bluish-white lustrous metal. It is very soft, highly malleable, ductile, and a relatively poor conductor of electricity. It is very resistant to corrosion but tarnishes upon exposure to air Lead Uses Lead was used frequently for roof, cornices, tank linings and flashing strips for waterproofing
Week 6 E-learnings
Tin properties Ordinary tin is a silvery-white metal, is malleable, somewhat ductile and has a highly crystalline structure Tin uses Tin resists distilled, sea and soft tap water, but is attacked by strong acids, alkalis and acid salts. Oxygen in solution accelerates the attack
Week 6 E-learnings
Titanium properties Titanium is well known for its excellent corrosion resistance and for its high strength- to-weight ratio. It is light, strong, easily fabricated metal with low density. In thin sheets, it is not very stiff and appears as pillowy rather than flat Titanium Uses Titanium is used in strong light-weight alloys, making an attractive and durable cladding material, though it is often prohibitively expensive
Week 6 E-learnings
Bronze properties Bronze is a particularly important alloy of copper and tin. Like copper it is corrosion resistant but it is much harder and can be used in engineering and marine applications Uses Bronze parts are tough and typically used for bearing, clips, electrical connectors and springs
Week 6 E-learnings
Brass (copper+zinc) Properties: Brass is malleable and has a relatively low melting point and is easy to cast. It is not ferromagnetic Brass Uses Brass parts are tough and typically used in elements where friction is required such as locks, gears, screws, valves. It is also commonly found in fittings.
Week 6 Class Activity
In this weekâ&#x20AC;&#x2122;s studio, everyone got to present what they saw in their site visits. The site I went to was a three-storeys house. The third floor was still under construction so it has no roof and there are only wooden structures on there. There was just a little use of concrete in the site comparing to the sites that others groups have gone to. Concrete was only used on the four main walls on the building, which is show in the sketch on the right.
Also, we have seen trussed roofs in the second floor of the site, a sketch of the trussed roof is shown below
Studs , noggings and bracings are widely used among all the wooden
structures in the building. Studs are use to support the roof, bracings and noggings prevent studs from tilting and falling off. Sketches of noggings, studs and bracings are shown below
Week 7 E-Learnings
Detailing for Heat and Moisture For water to penetrate into a building all of the following three conditions must occur:
An opening
Water present at the opening
A force to move water through the opening
Remove any one of the conditions and water will not enter
Week 7 E-Learnings
Detailing for Heat and Moisture To prevent water penetrating into a building, three different strategies are employed:
Remove openings
Keep water away from openings
Neutralize the forces that move water through opening
One is sufficient but if Two of More strategies are pursued then there is a added security in case one fails
Week 7 E-Learnings
Openings can be planned elements such as windows, doors, skylights etc. Or unplanned openings in the building fabric created by: Poor construction workmanship Deterioration of materials Common techniques used to remove openings to prevent water penetration include seal the openings with: Sealants (eg. Silicone) Gaskets (eg. Performed shapes made from artificial rubbers etc.) Both sealants and gaskets rely heavily on correct installation and will deteriorate over time due to weathering. Keeping water from openings is a commonly used strategy construction detailing. This means that water is directed away from any potential openings in the building by: Grading roofs so that the water is collected in Gutters which then discharge the water to Downpipes and Storm water systems. Overlapping cladding and roofing elements (eg. Weatherboards and Roof Tiles). Sloping window and door Sills and roof/wall flashings. Sloping the ground surface away from the walls at the base of buildings.
Week 7 E-Learnings
Typically use slopes and overlaps to carry water away from the building using the force of gravity Gravity Strategies
With gusts of wind, water can still be moved through a complex labyrinth if there is a difference in the air pressure between the outside and inside. The water is ‘pumped’ from the high pressure to the low pressure
Neutralizing the Forces Surface Tension and Capillary Action Strategies Typically use a drip or a break between surfaces to prevent water clinging to the underside of surfaces. These gaps and breaks prevent water reaching and entering opening because the surface tension of the water is broken at the drip location. Instead, the capillary action movement of the water stops and the water is released in drop form
Air Pressure Differential Strategies
Rain Screen Assembles: If an air barrier is introduced on the internal side of the labyrinth, a ventilated and drained pressure equalization chamber is created and the water is no long ‘pumped’ to the inside of the assembly
Week 7 E-Learnings
Detailing for Heat Controlling heat: Heat gain and heat loss occur when: Heat is conducted through the building envelope. The building envelope and building elements are subjected to Radiant Heat sources. Thermal Mass is used to regulate the flow of heat through the building envelope. Effective control of heat gain and heat loss saves energy, saves moent and increases comfort levels for building occupants
Week 7 E-Learnings
Plastics Sourcing – the plastics we use today are made from elements such as: Carbon, silicon, hydrogen, nitrogen, oxygen and chloride combined by chemical reactions into monomers. The monomers combine with each other to form polymers. Polymers are long chains of monomers that make the substance we call plastics. Thermoplastics – moldable when heated and become solid again when cooled. Can be recycled. Thermosetting Plastics – can only be shaped once. Elastomers – refer to separate e-MODULE Plastics properties: The hardness is medium to low and the frailty is low to medium as plastics generally will not shatter or break. The ductility is high when in heated state and varied in cold state. The flexibility is high flexibility and plasticity. Many plastics are waterproof and the density is low. The conductivity is very poor of heat and electricity. The durability can be very durable and the reusability is high for thermoplastics and elastomers. The sustainability embodied energy varies greatly between recycled and not recycled. Also, the cost is generally cost effective.
Week 7 E-Learnings
Paints Paints are liquid until they are applied on a surface forming a film that becomes solid when in contact with the air. Their main purpose is to protect a particular element. Clear paints are called lacquers or varnishes. Oil Based Used prior to plastic paints Very good High Gloss finishes can be achieved Not water soluble Water based Most common today Durable and Flexible Tools and brushes can be cleaned with water Paints properties: The Color of the paint should resist fading. The durability needs to resist chipping, cracking and peeling. The Gloss of the surface finishes can range from matt through to gloss. For flexibility, the water based latex paint is more flexible than oil based paint
Week 8 E-Learnings
Door & Door frame terminology Glass: components Formers are the basic ingredient used to produce glass. Any chemical compound that can be melted and cooled into a glass is a former Fluxes help formers to melt at lower and more practical temperatures Stabilizers combine with formers and fluxes to keep the finished glass from dissolving or crumbling
Glass – History 1 century BC – Blown Glass 11-13 century – Sheet Glass – sliced from blown glass 17 century – Lead Crystal – lead oxide added to make glass easier to cut 17 century – Plate Glass – improved optical qualities 1910 – Lamination – celluloid layer inserted between two sheets of glass 1959 – Float Glass – molten glass is poured over a bath of molten tin
Week 8 E-Learnings
Properties of Glass 1. Porosity/Permeability – Non-porous/Waterproof 2. Density – Medium high. Approximately 2.7 x more dense than water 3. Conductivity – transmits heat and light but not electricity 4. Hardness – high but can be scratched with a metallic object 5. Fragility – high. Differs depending on the type of glass (tempered glass is not as brittle as float glass) 6. Ductility – very low 7. Flexibility/plasticity – very high flexibility and plasticity when molten/low to very low when cooled 8. Durability/life span – typically very durable – chemical rust and rot resistant 9. Reusability/Recyclability – very high 10. Sustainability and carbon footprint – typically high embodied energy and carbon footprint but ease of recycling/reuse makes it a popular sustainable product 11. Cost – generally expensive to produce and transport
Week 8 E-Learnings
Clear float glass ideal in low risk/low cost/small size glazing scenarios. Breaks into very sharp and dangerous shards Produced by heating annealed glass to approximately 650oc, at which point it begins to soften. The surfaces of this heated glass are then cooled rapidly creating a state of high compression in the out surfaces of the glass
the simplest and cheapest glass product available in the market. No further treatment beyond the float fabrication Flat Glass- float glass (typically sheets of clear or tinted float, laminated, tempered, wired, etc.)
Tempered glass
Laminated Glass A tough plastic interlayer is bonded together between two glass panes
This improves the security and safety of the glass product as even though the glass can still crack, the sharp fragments tend to adhere to the plastic rather than falling apart
Glass
As a result the bending strength is increased by a factor of 4-5 times that of annealed glass and makes it make into small, pellet shaped pieces rather than sharp shards, improving the safety of the product
Shaped Glass (curved, blocks, channels, tubes, fibres)
Ideal to use in highly exposed situations or when the size required are particularly large Patterned Glass – made with a rolled glass process – typically used when privacy and light are required
Photovolt -aic Glass – with integrated solar cells Glass Channels – used in façade systems
Tinted Glass – useful in sunexposed situations to reduce visible light transfer Wired Glass- similar concept to laminated glass – a steel wire mesh is used instead of a plastic film – traditionally accepted as a low-cost fire glass Slumped and Formed Glass – used as design features
Curved Glass – this type of glass is produced in moulds that are Glass Fibres – created to hair-like meet the strands – used specific design in requirements – telecommunica expensive tions
Week 8 Class Activity In this week, drawings of the Oval Pavilion-Redevelopment were given to us. And we are assigned with different part of the building. What we have to do for the next and the next week is to reproduce the drawing in a 1:1 scale. During the studio we went to the actual building and look at the parts we are suppose to draw. The photos below shows the actual part of the building which I was assigned to draw.
structures and design from the book and e-learnings. Such as the insulations, rough wood, joints, double glazings, concrete ceiling etc. The sketches below indicate where all those appear in the drawing
Below is the drawing which I was assigned to draw for the week.
Through looking at the drawing and the actual building, I can identify some
Week 9 E-Learnings
Materials: Monolithic or Composite Monolithic materials are: A single material, or Materials combined so that components are indistinguishable (eg. Metal alloys) Composite materials are created when: Two or more materials are combined in such a way that the individual materials remain easily distinguishable Composite materials come in many forms. But they can be grouped in to four main types â&#x20AC;&#x201C; Fibrous, laminar, particulate and hybrid
Week 9 E-Learnings They are made from cellulose fibers, Portland cement, sand & water. The common forms are sheet & board products and shaped products such as pipes, roof tiles etc. The common uses cladding for exterior in interior walls, floor panels. Benefits are that fiber cement building materials will not burn, are resistant to permanent water and termite damage, and resistant to rotting and warping. It is a reasonably inexpensive material
Fiber Reinforced Cement (FRC)
Aluminium Sheet Composites Materials
Fiber Glass They are made from a mixture of glass fibres and epoxy resins. The common forms are flat and profiled sheet products and formed/ shaped products. The common uses are transparent or translucent roof/wall cladding and for preformed shaped products such as water tanks, baths, swimming pools etc. Benefits are that fiberglass materials are fire resistant, weatherproof, relatively light weight and strong
Timber Composites They are made from combinations of solid timber, engineered timber. The common forms are timber top and bottom chords with gal. steel or engineered board/plywood webs. The common uses beams and trusses. Benefits are that minimum amount of material is used for maximum efficiency, cost effective, easy to install, easy to accommodate services
They are made from aluminium and plastic. The common forms are plastic core of phenolic resin lined with two external skins of thin aluminium sheet. The common uses that are as a feature cladding material in interior and exterior applications. Benefits are reduced amounts of aluminium are required and lighter weight, less expensive sheets can be produced, which are weather resistant, unbreakable and shock resistant. A variety of finishes can be specified and â&#x20AC;&#x2DC;seamlessâ&#x20AC;&#x2122; details can be achieved with careful cutting, folding, bending and fixing
Fiber Reinforced Polymers They are made from polymers with timber, glass or carbon fibres. The common forms often associated with molded or pultrusion processed products. The common uses decking, structural elements such as beams and columns for public pedestrian bridges using glass or carbon fibre reinforced polymer rebar. Benefits are that high-strength FRP materials with glass or carbon fibre reinforcements provide a strengthto-weight ratio greater than steel. FRP composite materials are corrosion-resistance
Week 9 Site visit In this week, we went to a site visit instead of having a studio. The site is a commercial building under construction. We went up to the 12th floor and looked around the site. The photos below show the site we went to.
As we can see in the photos, the building is mainly made out of concrete. The photo above shows a giant pump pumping concrete from the ground to the 12th floor
The photo above shows the main support at the entrance of the building which is taking up most of the load from above
Week 9 Site visit
They also used giant glass on the sides of the building
Week 9 E-Learnings
Corrosion of Materials Example â&#x20AC;&#x201C; Statue Of Liberty History- the statue was designed by Auguste Bartholdi The Copper Skin is supported on an iron skeleton designed by Gustave Eiffel When copper is exposed to the atmosphere, it reacts with oxygen. The copper starts to dull, first becoming a darker brown color and then forming a green copper oxide patina Statue of Liberty: Galvanic Corrosion Initial Connection detail Consideration Galvanic corrosion between the copper skin and iron frame was considered at the time of construction and a solution that allowed for the separation of the two metals was devised
Week 10 E-Learnings
The First solution The two materials were separated at their junctions by a layer of shellacimpregnated cloth The problem Over time, the shellac-impregnated cloth became porous and actually held moisture at the joint between the two different metals. This provided good conditions for galvanic corrosion and the iron began to corrode What happened? The connection system started to fail as the build up of corrosion products (rust) expanded and pulled the rivets away from the copper skin
Week 10 E-Learnings
The second solution: To overcome this problem, the original iron armature frame was replaced with a Teflon-coated stainless steel structure. The selection of stainless steel was made after extensive corrosion resistance testing and consideration of the physical properties of the stainless steel and how well it would work with the existing copper skin The future The new system still includes two different metals and so will require ongoing inspections and maintenance
Week 10 E-Learnings In this week, we brought our 1:1 drawing to class and did a little presentation on what we have identified on the drawings
Insulations are used in this building to control the inside temperature from being too hot or too cold
Concrete was not the main component of the
building as we can see the design of the building and its surroundings are mainly made out of wood. They used rough wood some part of the roof system.
Double glazing is also used in the front of the building. Using double glazing can help to reduced the collected heat of the building, keeping the inside of the building from being too hot. This has similar functions as the insulations
Although concrete is not the main component of the building, it is still used to build part of the roof system (ceiling). Using concrete can make the ceiling more stable, reducing the chance of collapsing as concrete is quite a tough material comparing to other constructing materials