Columns are considered LONG: effective column length : the smallest cross section dimension is greater than 12:1. LONG COLUMNS become unstable and fail by BUCKLING.
The EFFECTIVE length : of the column is changed is measured between the points of contraflexure
WEEK 5 – Columns, grids and wall systems Short and Long columns: COLUMNS are vertical structural members designed to transfer axial compressive loads. （SLENDER MEMBERS） SHORT COLUMNS are shorter (length) and thicker (crosssection). Columns are considered SHORT effective column cross section
： length:the smallest dimension is less than
12:1. SHORT COLUMNS: the column cross exceed the
the load applied to section does not compressive strength
of the material. Compressive Load (N) / area Short columns: compressive load is
Strength (Pa) = (mm2) shorter when a applied fail by crushing
(shear)when the compressive strength is exceeded
LONG COLUMNS are taller (length) and slimmer (cross-section).
Walls systemďźš Structural frames: Concrete frames (grid of columns+ concrete beam ) Steel frames (grid of steel columns+ steel girders, beams) UC CHS RHS Timber frames( grid of timber posts/poles connected to timber beams Load bearing walls: Concrete: in situ or precast Masonry (core hollow concrete blocks/ grout filled cavity masonry): Solid masonry- create with single or multiple skins of concrete masonry Cavity masonry- two skins of masonry (the presence of a damp proof course and weep holes in the wall are indicators that the wall is a cavity wall) Stud walls - light gauge steel framing - timber framing
Stud framing: top plates, bottom plates, vertical studs, noggins, cross bracing and ply bracing.
Brick veneer construction: one skin of nonstructural masonry and one skin of structural frame wall.( CHEAPER) Brick cavity construction
From wood to timber: Wood: heartwood sapwood cambium cell layer inner bark outer bark Early wood: thin large cell and color Late wood: thick small cell dark and gives the growth ring Growth: one ring per year Grain direction: determines the structure performance of wood The timber is strong parallel to grain + stiff parallel to the grain Weak perpendicular to grain Timber seasoned: - to adjust the moisture content so the timber is appropriate for the intend use. - to provide increased dimensional stability Free moisture Bond moisture is remover form the wood Moisture removed: Air seasoning dying Kiln seasoning dying (typically) Solar kiln seasoning Type of timber: Softwood: radiata pine, Cypress pine, Hoop pine and Douglas fir Hardwood: Victorian ash, Brown box, Spotted gum, Jarrah, Tasmanian oak and Balsa wood Green sawn Quarter sawn- Growth rings parallel to short edge Back sawn- Rings parallel to long edge of piece Radial sawn- Face is always a radial cut.
Timber properties: Hardness- medium-low Fragility- medium-low Ductility - low Flexibility- high flexibility and medium plasticity Porosity- high Density extremely varied depending on timber type Conductivity- poor conduct of heat and electricity
Durability - can very durable Reusability- very high Sustainability- very low embodied energy. Cost- generally cost effective
Engineered timber products: LVL - Laminated Veneer Lumber mainly
structural ( beams, posts, portal frames) Glulam- glue laminated timber - mainly structural ( beams, posts, portal frames) CLT- Cross Laminated Timber - structural panels( horizontal and vertical) Plywood-structural bracing/ flooring/ formwork/ joinery/ marine applications
MDF- Medium Density Fiberboard - non-structural applications Chipboard and strandboard - as part of structural systems - flooring/ cladding finish
I Beams Box beams Timber flanged steel web joists
Cavity flashing: rishing damp(?) Falling damp The materials that we used: rulers, balsa, chopping board, knife, PVA glue. Post board (as base) 1. We start Timber considerations: by Knots- weak points Water related damage - swelling, shrinkage can cause cracks Insect attack Heat- sunlight, fire Chemical exposure
Class tasks: Descriptions: Develop a working understanding of the structural system of a building through analysis of architectural and structural documentation and detailed model making. Floor joists/ BOX BEAMS rafters JOISTS
cutting balsas into 7cm strips. We stick two strips together to make the foundation pillar( as picture 3, above). 2. We cut the rest of the balsa in scale, in order to build the top of our structure (picture 4). 3. We draw the position of the pillar on the base and use PVA glue to stick on the post board, but because of PVA glue take really long time to dry, so we ended up with fail. The model falls as soon as we place the top on the foundation pillar. The actual model should be like this.
Mind map for week 5 Flat roof （pitch 1~3） Pitched and sloping roofs （pitch >3） Concrete roof ：Flat plates of reinforced concrete
Steel framed roofs： Flat: combination of primary and secondary roof beams Sloping: roof beams and purlins and light sheet metal roofing Portal frames: a series of braced rigid frames( two columns an done beam) with purlins for the roof and grits for the walls
Truss roofs：are framed roofs constructed from a series of open web type steel or timber elements
Space frames：are 3D plate type structures that are long spanning in two directions (linear cross) Light framed roofs (timber, color-formed steel section) Gable roofs- characterized by a vertical, triangular section of wall at one or both ends of the roof - common rafters - ridge beams - ceiling joists
Week 6 â€“ Spanning and Enclosing space TRUSS: STEEL TRUSS are fabricated by welding or bolting structural angels and tees together to form the triangulated framework. Type of truss: Pitched trusses, bowstring trusses, flat truss, Pratt trusses, Howe trusses, Belgian trusses, fink trusses, warren trusses, bowstring trusses, raised-chord trusses and crescent trusses.
Before we make the model. Our group spent some time on the site drawing. We were trying to figure out what dose our part look like. And at the same time, we calculate the length for each part (scale up)
Hip roofs (timber, color-formed steel section) Hip roofs are characterized by a vertical, triangular section of wall at one or both ends of the roof -common rafter - hip rafter -valley rafter - jack rafter - ridge beams -ceiling joists
Introduce to metalMetal are malleable and ductile and no brittle. Types of metal: Ferrous: iron Non-ferrous: all the other metals Alloys: combinations of two or more metals Properties: Hardness- varied. Depending on type Fragility- low Ductility - high Flexibility- medium Porosity- impermeable Density- high Conductivity- very good conductors of heat and electricity Durability - can very durable Reusability- high Sustainability- very high embodied energy. Cost- generally cost effective Considerations Oxidation and corrosion
Ferrous metals (iron): Properties: 1. Distinctive properties 2. Significant and important magnetic properties 3. Very reactive chemically 4. Good compressive strength
Non-ferrous metals Aluminium Properties: -very light compared to other metals -non-magnetic and non-sparking -easily formed, machined and cast (Pure Al- soft and lack of strength.) Uses- extruded sections are common for window frames and other glazed structure -door handles - rolled Al is used for cladding panels, heating and A.C system
Copper Properties: -Oxidization -Very malleable and ductile -Good conductor of teat and electricity Uses - roofing material - hot and cold domestic water and pipework - electrical cabbing
Types and uses Wrought iron- bars for windows and doors and for decorative elements Cast iron- contemporary construction due to its weight and brittleness. Iron alloys- steel Steel is an alloy of iron with carbon being the primary additional alloy element. -very strong and resistant to fracture -transfers heat and electricity -can be formed into different shapes -long lasting and resistant to wear Uses: steel sheeting Cladding and roofing- must protected from weather exposure.
Zinc Properties: 1. Bluish-white, 2. Lustrous metal. 3. Brittle at ambient temperatures (malleable at 100~150) 4. Reasonable conductor of electricity Uses - galvanizing - help protect the iron from corrosion(roofing material ) - cladding material( wall and roof) Lead Soft, highly malleable, ductile relatively poor conductor of electricity. Uses - roofs, cornices tank linings and flashing strips for waterproofing - Toxic
Tin Highly crystalline structure, malleable Oxygen in solution accelerates the attack Uses - building for lining lead pipes - protective covering for iron plates - small gas pipes/tubing
Titanium Excellent corrosion resistance High strength-to-weight radio . Used - in strong light-weight alloys -cladding material -prohibitively expensive
Bronze( copper+tin) Particularly important alloy of copper and tin Corrosion resistant Uses -bearing, clips, electrical connectors and springs
Brass Malleable, relatively low melting point an is easy to cast Not
ferromagnetic Uses - in elements where friction is required such as locks, gears, screws, valves
Property: Property development in its general sense is about: - space creation - profits made and lost
capitalizing on opportunity knowing
CFC – Compressed Fiber Cement FC – fiber cement (isn’t strong)
Frame: Frame Timber frame
Primary Floor bearer Roof
Beam - hot rolled - UB, UC, PFC
Secondary Joist Pine Rafter Purlins - cold formed
Top chord+ bottom chord
Simply supported 2 points of support
stronger support 3 points of support
Class task: Descriptions: Full size part one presentation: Present your model to the studio group, explaining the various components of the structural systems, the materials they are made from and the fixing methods used.
Week 7 â€“ Detailing strategies 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 Prevent water penetrate into the building Remove openings or Keep water away from openings or Neutralist the forces that move water through openings (Two or more strategies - added security in case one fails)
Detailing for moisture Openings can be: Planned elements -windows, doors etc Unplanned openings created by - poor construction workmanship? -deterioration of materials Techniques of Remove Openings to prevent water penetration included seal the openings with: -sealants -gaskets Neutralizing the forces: the most secure strategies for keeping water out of buildings are those based on neutralizing the forces which move water. Forces -gravity (slopes and overlaps to carry water away from the building) - surface tension and capillary action (drip or break between surface) - momentum (windblown?rain, moisture and snow can move through simple gaps) - air pressure differential( difference in the air pressure between the outside and inside.)
Controlling heat: Heat gain or loss: - 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. Conduction: -thermal insulating to reduce heat conduction -thermal breaks (help transfer) -double glazing (reduce the flow of heat) Radiation -reflective surfaces -shading systems Thermal mass -Large areas of exposed thermal mass can be used to absorb and store heat over a period of time. use of materials -masonry -concrete -water bodies
Detailing for heat If a building has: An opening Air present at the opening A force to move air through the opening Air will move through the building and the spaces will become drafty in cold weather. Strategies to stop air leakage -Eliminating any one of the causes -Wrapping the building in polyethylene or reflective foil sarking to provide an air? barrier -Weather stripping around doors and windows and other openings.
Rubber: Natural rubber (from the rubber tree) Uses- seals Gaskets and control joints Flooring Insulation
Hosing and piping Synthetic rubber (syntheisised in a laboratory generating a range of variations) Uses: EPDM-Gaskets and control joints
Neoprene -control joints Silicone- seals Properties: Hardness- hard rubber resist abrasion, soft rubber provide better seals Fragility- low Ductility - high Flexibility- high Porosity- considered waterproof Density- 1.5 times density of water
Conductivity- very poor conductors of heat and electricity Durability - can very durable Reusability- high Sustainability- embodied energy varies greatly between natural rubber (low) and synthetic rubbers (medium) Cost- generally cost effective Considerations Water related damage Rubbers can lose their properties when exposed to weather (sunlight) Protection Avoid or minimise sun exposure.
Plastic Made of- carbon, silicon, hydrogen, nitrogen, oxygen and chloride Types and uses 1. Thermoplastic: mouldable when heated and become solid again when cooled. Recycled Polythelyne Polymethyl methacrylate (Perspex) Polyvinyl chloride (PVC) Polycarbonate 2. Thermosetting plastics: can only be shaped once Melamide formaldehyde (laminex)- finishing surfaces Polystyrene (stryene)- insulation panels 3. Elastomers- refer to separate e-module EPDM Neoprene Silicone
WEEK 8 â€“ doors and windows Properties: Hardness- mediumn-low Fragility- low-mediumn Ductility - high Flexibility- high Porosity- many plastics are waterproof Density-low (0.65times density of water) Conductivity- very poor conductors of heat and electricity Durability - can very durable Reusability- high for thermoplastics and elastomers Very limited for thermosetting plastics Sustainability- embodied energy varies greatly between recycled and non-recycled Cost- generally cost effective Consideration Plastics properties degrade when exposed to weather (sunlight) Protections Avoid or minimise sun exposure Some plastics have very high expansion/contraction coefficients
Paints Paints are liquid until they are applied on a surface forming a film that becomes solid when in contact with the air Components Binder- the film-forming component of the paint Diluent- dissolves the point and adjusts its viscosity Pigment- gives the paint it's color and opacity.( can be natural or synthetic) Types and uses -Oil based -Water based
Doors and windows Door and door frame terminology Door leaf
Timber doors and frames
and frame Steel doors and frames
Windows Window sill and window jamb
Timber window frame Aluminum doors and frame Steel doors and frames
Curtain walls: windows or exterior wall system
Glass Components Formers- are the basic ingredient used to produce glass. Fluxes- help formers to melt at lower and more particle temperatures Stabilizers- formers+fluxes History: Blown glass sheet glass lead crystal plate glass lamination float glass Types and uses Flat glass: sheets of clear or tinted float, laminated) Shaped glass: curved, blocks, channels, tubes) Float glass (most common glass) 1. Clear float glass 2. Laminated glass 3. Tempered glass Other types: Tinted glass Wired glass Patterned glass Curved glass Photovoltaic glass Class channels Slumped and formed glass Glass fibers
Properties Porosity-non-porous/ waterproof Density-medium-high Conductivity- transmits heat and light but not electricity Hardness- high. Can be scratched with a metallic object Fragility- high Ductility - very low Flexibility- very high Durability - typically very durable Reusability- very high
Class task: Descriptions: To develop an understanding of the actual size of construction elements and the detailed relationship of individual parts. To experiment with the implications and difficulty of translating a scale drawing to a full size drawing (or a real part of the construction).
1. First finding the detailed section drawing of my part 2. Calculate the scale (times 10) 3. The main part of this structure is an UC, so I start by drawing the UC first and then draw the rest part. It is easy to position UC first rather draw whole section on the paper.
WEEK 9 â€“
Strategies 4. After draw the section in pencil, use black fineline pen to highlight the main part of the section. 5. Then using the symbol that we have learned before, to represent different material that the section used Steel, UB, Cold formed steel frame, Concrete blocks
Construction detailing Movement joints Compressed
Health and safety Repairable suffice and resistance to damage Cleanable surface Construct-ability Other considerations -Off the shelf items -Detailing to suit construction expertise
Composite materials Monolithic materials are: -a single material - material combined so that components are indistinguishable(metal alloys) Composite material are created when: Two or more materials are combined in such a way that the individual materials remain easily distinguishable. A composite is formed from - Combination of materials, which differ in composition or form - Remain bonded together - Retain their identities and properties - Act together to provide improved specific or synergistic characteristics not obtainable by any of the original component acting alone
MATERIALS (FRC) Fibre Reinforced cement
Made from- cellulose ( glass) fibres, Portland cement, sand and water Common forms- sheet and board products and shaped products (pipes, roof tiles) Common use- cladding for exterior or interior wall, floor panels Benefit- not burn , - Resistant to permanent water and termite damage -Resistant to rotting and warping -Inexpensive material Fibreglass Made from- a mixture of glass fibres and epoxy resins Common form- flat and profiled sheet products Formed/ shaped products Common uses- transparent or translucent roof/wall cladding and for preformed shaped products ( water tanks, baths, swimming pool) Benefit- fibreglass material are fire resistant, waterproof, light weight and strong ( other samples) Aluminum sheet composites -Al and plastic Timber composites -combinations of solid timber, engineered timber, galvanized pressed steel Fibre reinforced polymers -polymers(plastic) with timber, glass or carbon fibres
Moment joints Types of moment joints: Control joints Expansion joints Isulation joints
Class tasks: Descriptions: To develop an ability to understand an unfamiliar building site and the different systems used in Fibrous Laminar Particulate Hybrid Products containing discontinuous or continuous fibres
Gravel and resins
Combination of two or more composite types
This weekâ€™s tutorial, we went to two different buildings that under construction. The first site is a public building. Steel structural (flooring) ďƒ picture 4
Picture 1 steel column/ steel to steel connections Picture 2 the timber runs parallel to the ceiling -- rafter Picture 4 door head Picture 5 typical timber frame
Thing do Mind map:
This is the second site, which is a high-rise building and it is apartment. Picture 3-carridor is concrete to concrete Picture 4- the pipe in the room The room has smoke detector, no phone lines, gas and air conditioning.
wrong The building that cracks The basement of the building: Underground carprak Things need to consider: Materials selection These steel poles that hold the concrete wall. Flat steel sheeting on plywood: Each side has to have two Timber plywood glued to timber stud walls Flat steel sheet glued to plywood Thermal differences Blistering and peeling sheets Cut edges
performance Coastal marine exposure Exposure
Week 10 -When things go wrong Tale of corrosion Galvanic corrosion: Copper oxidization: When copper is exposed to the atmosphere, it reacts with oxygen. 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. Solutions 1 the two materials were separated at their junctions by a lyer of shellac-impregnated cloth. 2. The selection of stainless Steel was made after extensive corrosion resistance testing and consideration of physical properties of the stainless steel and how well it would work with the existing copper skin Corrosion (oxidation) -Metal (potential difference between these) -Electrical difference -Medium to transform electrons -Oxygen The depth it spans, the strong he structure will
Construction workshop Class tasks: Descriptions: To develop an understanding of the actual size of construction elements and the detailed relationship of individual parts. To experiment with the implications and difficulty of translating a scale drawing to a full size drawing (or a real part of the construction).
My section is not easy to see form the ground
Activities: 1. 2.
In group of 3-4, design and construct a structure that must span 1000mm. Our group is going to construct a--
Timber frame wall
3. We used the tools and fixings that were provided. We used screw are much as we could to nail the timber together.
We put in the testing cradle. And the load that structure have is not as high as we excepted.
4 The way this structure breaks. I understand that nails creates weakness itself So it doesn’t mean it will be stranger if we use a lots of nails to construct the model.
Other group’s structures:
Referencing Ching, Frances. D. K, Building Construction Illustrated, 2008 Constructing environments E-learning, 2014