LogbooK Week1 Xiaodi Zhang 657695 1
Science & engineering principles
Materials
Structural principles
Labor types
Construction System
•Strength •Stiffness •Shape •Material behavior •Economy & sustainabil ity
Language of construction
Construction term
Site processes
Construction drawings
•Tension---steel •Compression---steal, concrete, stone, brick 2
•Aim: To build a tower with exit by using MDF as soon as possible. •Our group’s method: Built a rectangular tower firstly, and then made the exit by “destroying” part of the tower.
Step1: Build the base
Loan path of the wall
The structure is firm because the load from top bricks is transferred to the bricks underneath and the load from all the bricks is transferred to the ground. The ground has the reaction to the base which is the same magnitude and the 3 opposite direction as the load from bricks.
Step2: Transfer the shape into pyramid ďƒ˜In order to make the tower taller and faster, we decided to make a pyramidal structure at the top of the tower. Because of the time limit, we did not make a spire for the tower.
Step3: Make the exit by destroying the wall
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The structure is still firm after the “destruction” because the bricks at the edges of the exit transfer their load to the bricks beneath, and the load from those bricks is gradually transferred to the ground. However, the structure will collapse if the gaps between bricks are too big as the contact surface is too small to let the enough load transfer efficiently. Step4: Examine the size of the exit
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Cameron, R. 2014, Introduction to Construction Materials, The University of Melbourne, Melbourne, Australia. Cameron, R. 2014, Construction Overview, The University of Melbourne, Melbourne, Australia.
Cameron, R. 2014, Basic Structural Forces, The University of Melbourne, Melbourne, Australia.
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LogbooK Week2 Xiaodi Zhang 657695 7
Explored how firm a structure was by making models by straws
• The surface of straws attached to the table is so little that could be estimated as points. When a vertical force is pushed on the model, there is too much pressure on the base points. Additionally, straws are flexible so that, generally, they are not firm enough to withhold forces. These three structures are all attached to the table by points and there are no extra structure to improve the stiffness of straws, therefore the straws are either together or separated under the pressure.
• The attaching surface is changed from a point to a short straw, but the straws are only bonded at the top. So when a vertical force is added on the model, it will be separated. • Load path • An example of rebuilding the model •By adding triangle structure into the model, the base is firmer than before. And the “beams” can help to reduce the flexibility of the straws.
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Structural Connection Structural Systems& Form (Cameron Symbol (Cameron 2014) 2014) • Solid System (Compression is the main Roller Joints Load path • Load path transmits structural action) Reaction vertically Ex. Pyramid • Allow the horizontal • Surface System movement Ex. Shell Structure--- Opera House • Skeletal System (the most common system in construction) Pin Joints Ex. The bird nest in Beijing • Load path transmits vertically & • Membrane System horizontally Load path • Hybrid System (ETFE) • Allow rotation movement Ex. The swimming cube in Beijing Reaction Construction System (Ching 2008) Fixed Joints • Structural System Ex. Columns, beams, loadbearing walls…• Load transmits vertically, horizontally & rotationally •Restrict any form of movements • Enclosure System Ex. Roof, exterior walls, doors, windows. Load path •Mechanical System Ex. Ventilating systems, the sewage disposal system… 9 Reaction
Aim: To build a tower as high as possible.
Step1: Make the base of the tower Step2: Build the upper structure
Load path of the tower • Triangle is the basic shape used in the tower as it has firm structure and it needs less pieces of MDF to build.
Prediction about the tower: • It will stand firmly. • It will twist under the vertical force.
• The interaction and beams are made to reduce the flexibility of the MDF material. When pieces are bonded together, it is less possible to move around.
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Vertical Force
Vertical Force
Result2: The whole structure twisted badly.
Result1: The base of the tower twisted badly while the upper structure had no obvious change.
Reason: • The centre of gravity of the triangle structures were not precisely on a vertical line, which results in unequal and unbalanced load transmitting to the ground. When the three pieces of the base were under different magnitude of force, the structure would twist.
• In the 2nd situation, a triangle structure was broken, which makes the upper structure more flexible than before. Therefore the whole structure twisted.
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Cameron, R. 2014, Structural Connection, The University of Melbourne, Melbourne, Australia. Cameron, R. 2014, Structural systems and forms, The University of Melbourne, Melbourne, Australia. Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey.
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LogbooK Week3 Xiaodi Zhang 657695 13
Structural Elements (Structural elements 2014)
Footings & Foundations (Ching 2008) • Shallow footings Soil conditions are stable/soil bearing capacity is adequate. Pad footings • strut Main force: Types Strip footings compression Raft footings Main force: • Deep foundations • tie tension Soil conditions are unstable/soil bearing capacity is inadequate End bearing piles Types • beam Friction Piles 1. Driving long timber, steel or concrete members into the ground (Ching Methods Carry vertical loads 2008:3.24) • slab Supported by beams 2. Drilling into the ground and then filling Carry vertical or • panel the hole with concrete (Ching 2008:3.24) horizontal loads Brick course • shear diaphragm Bed • joints types Shear walls joint structure perpend Stretcher course Raked sometimes Header course Ironed combines with bracings aiming Brick-on-edge courseWeather struck to reinforcement Flush the structure. 14 Soldier course
ďƒ˜ Materials (Bricks, concrete blocks, stone 2014) Brick
Concrete block
stone
Main use
Walls, arch, paving
Walls, combination with steel
Walls (structural & non-structural), paving, cladding, aggregates, feature design elements
Hardness
Medium-high
Medium-high
Large Range: Igneous>metamorphic>sedimentary
Fragility
Medium
Medium
Largely geometry dependant
Ductility
Low
Low
Low
Flexibility/Plasticity
Low
Low
Rigid, low flexibility
Porosity/Permeability
Medium-low
Medium
Large range: pumice is very porous, granite is not porous
Density
Medium
Medium
Largely depending: usually 2.5 to 3 times more dense than water (granite, marble, sandstone, slate)
Conductivity
Poor conductivity of heat & electricity
Poor conductivity of heat & electricity
Poor conductivity of heat & electricity
Durability
Very durable
Very durable
Typically extremely durable
Reusability
High (can be reused with no change or easily crushed to be used as recycled aggregate)
Medium
Very high (can be reused with no change or reworked into new shapes for new uses)
Cost
Effective material cost + Labor cost
Effective material cost + Labor cost
Largely depend on labor and scarcety 15
Car Park
Lot 6 Café
Concrete
Concrete is permeable so that it can absorb moisture in the air, leading to oxidation on the surface.
Load Path
Concrete
Under the ground, the holed were dug to put piles. Arts
Horizontal structure to avoid deflection.
A gap was made to allow the concrete expand.
Water is drawn from the columns in the car park. Load Path Stairs on the west end of Union House Steal beams
Load Path
Steal truss Timber beam Concrete
PFC (“C” shape section)
I beams
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North Court Union House • Membrane System
Tie
• Rain water can pour from the hole to the ground
Tension
• Tension is the biggest load because of the wind
Tie
Beaurepaire Centre Pool
Load Path Aluminum frame
Steal frame Glass wall Shear diaphragm
New Melbourne school of design under construction • Concrete slab • Mild steel and galvanised steel
The shear wall is resistant to the loads from wind. Wind
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Cameron, R. 2014, Structural elements, The University of Melbourne, Melbourne, Australia. Cameron, R. 2014, Brick, The University of Melbourne, Melbourne, Australia. Cameron, R. 2014, Concrete Blocks, The University of Melbourne, Melbourne, Australia.
Cameron, R. 2014, Stone, The University of Melbourne, Melbourne, Australia. Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey. Newton, C. 2014, Footings and foundations, The University of Melbourne, Melbourne, Australia.
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LogbooK Week4 Xiaodi Zhang 657695 19
Key terms
Floor and Framing Systems (Ching 2008: 4.03)
Joist span
• Concrete Systems Element: concrete slab
Cantilever Joist(450mm) (generally timber) Joist spacing
Bearer (support joists)
Concrete
Foundation wall (concrete or bricks)
• Steel Systems Elements: heavy gauge structural steel members & light gauge steel framing. Combination: Sometimes steel systems combine with concrete slab system. • Timber Systems Elements: A combination of bearers and joists.
• Types • Advantage: -It is easy to manage the shape of the concrete when it is 1.In Situ Concrete liquid (Newton 2014). Main uses: retaining walls, footings and bespoke -High hardness, durable(Newton 2014) structural elements (Newton 2014) • Disadvantage: Joints: Construction joints and control joints are -Concrete will be weak when too much water is added, potential weak points for the in situ concrete and it will be too stiff (unworkable) when too little water (Newton 2014). is added (Newton 2014). 2.Pre-cast Concrete -Formwork, a temporary support, is used to hold liquid Main uses: retaining walls, columns and walls (Newton concrete before it hardens (Newton 2014). 2014) -It is permeable, which means steel bars would be Joints: Construction joints and structural joints oxidation if they are closed to the surface (Newton 2014). Advantages: -Poor vibration leads to air bubbles in the structure, and -More standardized (Newton 2014) air bubbles are negative to the structural performance 20 -Much faster to assemble in the site (Newton 2014) (Newton 2014).
Title Block List the types of information found in the title block on the floor plan page. -Consultants’ names, address and telephone number -Client -Revision -Drawing title -Drawing Number -Project Number -Scale -Project Architect -Project Director -Drawn -Date -Co-ordinated -Orientation Why might this information be important? -It is easy for navigation and communication between consultants, workers, architects,..etc. -People can get precise understanding of the drawings.
Drawing content- Plans (A21-01) What types of information is shown in this floor plan? -Wall types & height -FFL (Finished floor lever) -Room names & numbers -Window number -Floor materials -Legend -Annotation
Provide an example of the dimensions as they appear on this floor plan?
What units are used for the dimensions? Mm Is there a grid? What system is used for identifying the grid lines? There is a grid with horizontal grid lines 1 through 7 and vertical grid lines A through D.
What is the purpose of the legend? Legend is used as an explanation of construction drawings, which specifies details such as materials, FFL, etc. Why are some parts of the drawing annotated? Illustrate how the annotations are associated with the relevant part of the drawing. Annotation is used for the details and explanation which are not including in the legend. Annotations are associated by arrows.
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Illustrate how references to other drawings are shown on the plan. What do these symbols mean? In the A21-01 drawing:
Orientation and location of the Drawing number sections In the A40-01 drawing, there is a reference shown that it relates to A21-01. In the A21-01 drawing: Orientation and location for the sections Drawing number In the A30-02 drawing, there is a reference shown that it relates to A21-01. How are windows and doors identified? Provide and example of each. Is there a rationale to their numbering? What do these numbers mean? Window number in Room 2. 05 Door number in Room2.01
Room number The numbering system for windows and doors allows to numbering easily when changes are happened.
Illustrate how floor levels are noted on the plan? Finished Floor Lever is 46.600mm It is related to the abbreviation legend, which mentions the descriptions such as materials. Are some areas of the drawing clouded? Why? Yes. The clouded texts are relevant to new changes made by architects.
ďƒ˜ Drawing content- Elevations (A30-01) What type of information is shown in this elevation? How does it differ from the information shown on the plan? -Title block (scale, drawing number, etc.) -Legend and Abbreviation Legend -Orientation of the elevation (south, east,..etc.) -Reference to the plan -Context materials Shapes of the building and a few context are drawn in elevations. Are dimensions shown? If so, how do they differ from the dimensions on the plan? Provide and example of the dimensions as they relate to the elevation. Dimensions are shown in the elevation. In the plan, all the dimensions are shown, however, in the elevation, specific dimensions are shown.
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What types of levels are shown on the elevations? Illustrate how levels are shown in relation to the elevation. Ground level and levels above the ground level are shown on the elevations. Is there a grid? If so, how/where is it shown? Yes. Specific grid lines are shown in the elevation labeled with numbers. What types of information on the elevations are expressed using words? Illustrate how this is done. -Title Block (at the bottom of the page) -Legend and abbreviation legend (at the top and the top right of the page) -Clouded texts (by arrows sometimes) -Annotations (by arrows)
Illustrate how the doors and windows are identified on the elevations. Shapes of doors and windows are drawn in the elevation in a specific scale, and numbering system (the same as the plan) is also used.
ďƒ˜ Drawing content- sections (A40-1) What type of information is shown in this section? How does it differ from the information shown on the plan and elevation? -Reference on other drawings -Detail bubbles -Rooms’ name and functions -Numbering systems of rooms, windows and doors. -Context materials There are no legend and abbreviation legend in this section. In addition, there is no orientation annotation in the section. Illustrate how the section drawing differentiates between building elements that are cut through and those that are shown in elevation (beyond). Basement levels are shown in the section while they are not shown in the elevation. Furthermore, interior structures are shown in the section, such as timber frame, while interior structures are not included in the elevation drawing. Provide examples of how different materials are shown on the sections.
Door number in Room 2.04 Inner structure of the roof
Window number in Room 2.05
Timber framed floor Room number
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ground
ďƒ˜ Drawing content- details What sorts of things are detailed? Link details, scoop window details, canopy details, wall details Are the details compressed using break lines? Why? Yes. It helps people to find the location of the shown details in the whole structure. Provide examples of how different materials are shown on drawings at this scale. PFC Metal deck roof
External timber panel
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Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey. Newton, C. 2014, Concrete, The University of Melbourne, Melbourne, Australia. Newton, C. 2014, In Situ Concrete, The University of Melbourne, Melbourne, Australia. Newton, C. 2014, Pre Cast Concrete, The University of Melbourne, Melbourne, Australia.
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LogbooK Week5 Xiaodi Zhang 657695 26
Short and long columns
Wall Systems Structural Frames •Concrete frames
•Steel Frames
• Effective length
•Timber frames
Diagonal bracing is used to resist lateral forces (Ching, 2008).
Timber frames are used a grid of timber posts or poles which are connected to timber beams (Ching, 2008). (Ching, 2008)
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Concrete Load bearing walls
Pre cast
• Solid Masonry Solid masonry walls are constructed of hollow or solid masonry units (Ching, 2008). It may consist of multiple wythes bonded by grout, metal wall ties or horizontal joint reinforcement (Ching, 2008).
In situ Masonry
• Load bearing panels also support for spandrel panels over and link to other structural elements (Ching, 2008).
• Cavity Masonry (Ching, 2008) • Reinforced Masonry Reinforced masonry walls are constructed from core filled hollow concrete blocks or grout filled cavity masonry (Ching, 2008).
Steel reinforcing bars
Grout mix of portland cement, aggregate and water Bond beams are used as an alternative to steel or concrete lintels (Ching, 2008).
Stud Walls
Cavity masonry walls are characterized by damp proof course and weep holes (Ching, 2008). Advantages: -Better thermal performance and opportunities for insulation within the cavity (Ching, 2008). - Better waterproofing and the opportunity to run service within the wall cavity (Ching, 2008). Timber framing Light gauge framing steel
Brick veneer constructing 28
•Timber stud wall
Frames and walls
Fixed frame: -Fix joints -More resistant to deflection than Hinged frame (Ching, 2008) -More sensitive to thermal expansion and contraction (Ching, 2008)
(Source:https://www.dlsweb.rmit.edu.au/to olbox/buildright/content/bcgbc4010a/11_w all_systems/01_timber_wall_framing/page_ 001.htm)
• Brick veneer walls Brick veneer walls are combined with one skin of non-structural masonry (brick masonry) and one skin of structural frame wall (timber/steel frame) (Ching, 2008).
Hinged frame: -Pin joints -Pin joints allow hinged frames to rotate, which prevents high bending stresses (Ching, 2008) -Hinged frames will slightly flex when there is changes in temperature (Ching, 2008) Three-hinged frame: -Assembled by two sections connected with pin joints (Ching, 2008) -More sensitive to deflection than fixed frame and hinged frame (Ching, 2008) -Least affected by thermal stresses and support settlement than fixed frame and hinged frame (Ching, 2008)
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Materials: Balsa boards: We chose balsa boards because they were cheap and they could be easily cut into pieces.
Measuring tape: Measuring tape could bond the timber pieces immediately. Constructing Processes: Balsa boards were cut into different size of pieces according to the annotation in the section. The beam and the column were constructed together, while trusses were constructed separately. They were assembled as a whole structure after all the sections were constructed. And the outer frames were bonded at the end. Load path of column
Load path of a truss
Cross bracing is used to resist lateral forces and prevent deflection (Auburn University, 2014).
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Roof trusses are used to support roof deck and other materials covered the roof (Raftertales, 2014). In terms of the model, the benefits of using roof trusses are: •Roof trusses are able to span long areas (Raftertales, 2014). •Roof trusses can be assembled quickly and efficiently.
Long span
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Auburn University. (2014). Lateral stability of structures. Retrieved 04/20, 2014, from https://fp.auburn.edu/heinmic/StructuralStability/bracing.htm Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey. Raftertales . (2014). Types & Benefits of Roof Trusses. Retrieved 04/20, 2014, from http://www.raftertales.com/home-remodeling/roof-truss/
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LogbooK Week6 Xiaodi Zhang 657695 33
Key terms
Structural Steel Framed Roofs • Flat roofs Flat steel framed roofs consist of primary and secondary roof beams and purlins (Ching, 2008). • Sloping roofs Sloping steel roofs consist of roof beams, purlins and lighter sheet metal roofing (Ching, 2008).
Concrete Roofs • Portal frames Portal frames consist of a series of braced rigid frames (two columns and a beam)with purlins supporting for the roof and girts supporting for the walls (Ching, 2008).
• Concrete roofs are usually flat plates used for roof gardens and car parks (Guyer, 2009). • Reinforced concrete or precast slabs with a topping concrete are used (Ching, 2008). • The top surface is designed to slope towards drainages, and waterproof membrane is applied to the entire roof surface (Ching, 2008).
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Trussed Roofs
Introduction to metal
• Trusses are made by timber or steel (Ching, 2008). • Trussed roofs have high strength to material ratio (Ching, 2008). •Property: Metals are ductile, malleable and not brittle (Berns, Scheibelein& Theisen, 2008). •Type (Berns, Scheibelein& Theisen, 2008): -Ferrous metal: consist of iron -Non-ferrous metal: Consist of metals except iron More expansive and less common than ferrous metal Less possible to react with oxygen -Alloys: Combination of two or more metals
Hip Roofs Hip roofs are characterized by sloping ends and sides which makes an inclined projecting angle (Ching, 2008).
• Consideration: Water may lead to oxidation and corrosion for metals (Berns, Scheibelein & Theisen, 2008). To prevent metals from damage (Berns, Scheibelein & Theisen, 2008): -Avoid exposure to moisture
-Seal against moisture -Chemical treatment 35
ďƒ˜Site1 Location: 42, Liverpool St, North Fitzroy, VIC 3068 Architect: Robert Simeone
The site relates to a residential house by means of extending the current house structural frames. The foundation of the site is a raft slab footing. Above the footing, timber frames are used as structural members. And timber roof trusses are built above the wall frames.
ďƒ˜Site2 The site is relevant to the rebuilt of an old house. Brick veneer frame and timber roof were constructed for the preexisting house. Demolishing processes were doing during the site visit, and the roof was the first to be demolished, and followed by interior elements and finally, exterior structure was demolished. New concrete foundation was under construction after the demolishing process.
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References Berns, H., Scheibelein, G., & Theisen, V. (2008). Ferrous materials: Steel and cast iron. Berlin: Springer. Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey. Guyer, J. (2009). Introduction to roofing systems. Retrieved 04/23, 2014, from https://www.cedengineering.com/upload/An%20Intro%20to%20Roofing%20Systems.pdf
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LogbooK Week7 Xiaodi Zhang 657695 38
Arches, domes & shells • Dome
• Arch
• In order to be balanced, the line of thrust must be coincident with the arch axis (Ching, 2008). • The thrust is proportional to the total span and load, while inversely proportional to the arch rise (Ching, 2008).
• Vault Vaults are arched structure made by stones, bricks or reinforced concrete, which forms a roof or ceiling over a space (Ching, 2008).
(Ching, 2008)
(Ching, 2008)
• Domes are spherical surface structure with circular plans (Ching, 2008). • Meridional forces are always compressive (Ching, 2008). • Hoop forces are compressive in the upper place and tensile in the lower place (Ching, 2008).
• Shell • A shell is thin, curved plate structure which usually constructed by reinforced concrete (Ching, 2008). • On the surface, compression, tensile and shear loads are acting in the plate (Ching, 2008). A shell can support large uniform loads, but it is weak for concentrated loads (Ching, 2008).
(Ching, 2008)
• Translational surfaces are made by sliding a plane curve along a straight line or over another plane curve (Ching, 2008).
•Ruled surfaces are generated by the movement of a straight line (Ching, 2008).
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(Ching, 2008)
Drips and breaks between surfaces are used to prevent water penetration using capillary action (Ching, 2008).
ďƒ˜ Detailing for moisture • Three conditions of water penetration (Ching, 2008): -An opening -Water present at the opening -A force to move water through the opening • To prevent the water penetration: -Remove openings Sealants and gaskets are used to remove openings, and they need to be update over a period of time as they will deteriorate due to weathering (Neil and Leslie, 2014).
-Keep water away from openings 1.Gutters, downpipes and stormwater systems are used for grading roofs (Neil and Leslie, 2014). 2.Weatherboard and roof tiles are used for overlapping roofing elements (Neil and Leslie, 2014). 3.Sloping sills of windows and doors and wall flashing (Neil and Leslie, 2014). 4.Sloping the ground surface (Neil and Leslie, 2014). -Neutralize the force that move water through openings Forces under consideration including gravity, surface tension and capillary action, momentum and air pressure differential (Ching, 2008). Slopes and overlaps are used in the design of the flashing in order to remove water under gravity (Ching, 2008).
(Ching, 2008)
Interlocking seams prohibit the water penetration (Ching, 2008). (Ching, 2008)
(Ching, 2008)
Water may be pumped inside the building from high pressure atmosphere to low pressure atmosphere, and thus, air barriers are used for insulation (Neil and Leslie, 2014). 40
(Ching, 2008)
Detailing for heat •Heat changes relate to three conditions (Ching, 2008): -Heat conduction -Radiant heat -Thermal mass • Masonry, concrete and water bodies (thermal mass) are used to regulate the heat flow of a building (Allen & Rand, 2007). • Conduction is regulated by (Allen & Rand, 2007): -Thermal insulation -Thermal breaks (made by rubbers and plastic) -Double glazing or triple glazing • Radiation is controlled by (Allen & Rand, 2007): -Reflective surface -Shading systems (eaves, solar shelves, etc.)
• Air leakage occurs when (Ching, 2008): -An opening -Air present at an opening -A force to move air through the opening •To prevent the air leakage (Allen & Rand, 2007): -Eliminate causes -Wrapping polyethylene/reflective foil sarking to the building to provide the air barrier -Weather stripping around openings 41
References Allen, E., & Rand, P. (2007). Architectural detailing (2nd ed.). New Jersey: John Wiley & Sons, Inc. Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey.
Neil P, & Leslie, P. E. (2014). Detailing measures for moisture management in energy efficient demonstration homes . Retrieved 04/25, 2014, from http://c.ymcdn.com/sites/www.nibs.org/resource/resmgr/BEST/BEST1_036.pdf
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LogbooK Week8 Xiaodi Zhang 657695 43
Geometry & Moment of Inertia
• Deflection is a perpendicular distance which a spanning element deviates from the true course according to transverse loads (Ching, 2008). It increases with span and load, and decreases with the increasing of the moment of inertia of the section (Ching, 2008). • Bending moment is the external moment with a tendency to give rise to bend or rotate (Ching, 2008). • Resisting moment is the internal moment opposite and equal to the bending moment, made by the force couple maintaining equilibrium of the structure (Ching, 2008). • Bending stress is the combination of tension and compressive stresses resisting the transverse loads, and the maximum value of the bending stress is the furthest from the neutral axis (Ching, 2008). • Neutral axis passes through the cross section’s centroid, which there is no bending stress occurs (Ching, 2008).
• Transverse shear happens at the cross section of a member (Ching, 2008). • Horizontal/longitudinal shearing stresses are generated to prevent the slippage along the horizontal planes under transverse loads (Ching, 2008). • Vertical shearing stresses are generated to resist the transverse shear (Ching, 2008). The maximum value of vertical shearing stress is at the neutral axis, and it decreases towards outer surfaces nonlinearly (Ching, 2008).
(Ching, 2008)
• “Moment of inertia is the sum of the products of each element of an area and the suare of its distance from a coplanar axis of rotation” (Ching, 2008: 2.14).
(Ching, 2008)
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Terms
Door types (Ching, 2008): Swinging Door: • Exterior and interior use • Require spaces for swing • Most convenient way of operation • Most effective for acoustic and thermal insulation Bypass Sliding Door: • Exterior and interior use • Require no space for operating • Difficult for weather and sound seal Surface Sliding Door: • Exterior and interior use • Difficult for weather seal Pocket Sliding Door: • Interior use • No operating space
(Ching, 2008)
Folding Door: • Interior use • Occupy little operating space • Used to subdivide space
(Ching, 2008) • Exterior doors and windows should have weathertight seals when they are closed (Ching, 2008).
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Window types (Ching, 2008): Fixed Window: • 0% ventilating • A frame + stationary sash
Double-hung Window: • 50% ventilating • Two vertical sliding sashes
Casement Window: • 100% ventilating
Jalousie Window: • 100% ventilating • Used in mild climates for controlling ventilation
Terms Sash is the movable or fixed window framework where glass panes are set (Ching, 2008).
• Awning windows swing outward • Hopper windows swing inward • 100% ventilating
Sliding Window: • 50% ventilating • There are two or more sashes in a sliding window
Pane refers to one of divisions of a window, comprising by a single unit of glass set in a window frame (Ching, 2008). Glazing is the panes set in the window sashes (Ching, 2008).
Pivoting Window: • 100% ventilating • Sashes rotate 90 degrees or 180 degrees • Operated for maintenance, cleaning or emergency ventilation 46
Glass Flat glass is sheets of tinted or clear glass (Shelby, 2005). Float glass, tempered glass, laminated glass, wired glass, etc. are all belong to flat glass (Shelby, 2005). Shaped glass is generated into different shapes to fit curves, channels, blocks, fibres and tubes (Shelby, 2005). Float Glass is the most common type of glass production in the world (Shelby, 2005): -Clear Float Glass • The simplest and cheapest • No treatment after the float fabrication • Low cost • Breaks into sharp and dangerous pieces -Laminated Glass •
(http://www.metroglasstech.co.nz/catalogue/030.aspx)
• Safer than clear float glass because sharp fragments will stick to the plastic interlayer without falling apart after cracking (Shelby, 2005). -Tempered Glass • Tempered glass is produced by the heating annealed glass and then cooled it rapidly (Shelby, 2005). • High bending strength • Reinforced safety: breaks into small pieces (http://www.millworkoutlet.com)
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STEEL ANGLE FIXED TO HEADER BEAM
Equal angle
100*200 STEEL RHS, PT-13 (PAINT TO EXPOSED STRUCTURAL STEEL) Steel beam
CONTINUOUS WELDED TAB TO HEADER BEAM, TO MATCH PT-13 The welded tabs connect the steel beam to the glazing.
STRUCTURAL SILICONE The silicone bonded the glass to the steel frame (Ford, 2007).
GL-03 (GLAZING)
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STEEL ANGLE FIXED TO BASE ANGLE, PT-13
Internal space
External space
• Equal angle • It is a cove to provide the correct direction when the glass glazing was installed (Ford, 2007).
STEEL ANGLE RECESSED INTO CONCRETE SLAB, PT-13 Uneven angle
CONTINUOUS WELDED TAB TO BASE ANGLE, PT-13
VAPOUR BARRIER
Vapour barrier is utilized for damp proofing, usually made by plastic sheet (Ford, 2007).
FL-02 (CLEAR FLOOR SEALER) Floor sealer is a coating covering the floor surface to protect the floor (Ford, 2007). It is waterproofing so that the floor materials are stabilized (Ford, 2007).
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References
Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey.
Ford, E. (Ed.). (2011). The architectural details. New York: Princeton Architectural Press. Shelby, J. E. (2005). Introduction to glass Science and technology (2nd ed.). London: Cambridge : Royal Society of Chemistry.
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LogbooK Week9 Xiaodi Zhang 657695 52
Monolithic materials and composite materials
-Common forms: FC sheet (board and sheet products), shaped products like roof tiles or pipes.
Monolithic materials are single materials or materials with indistinguishable components, like metal alloys (Newton, 2014).
-Common function: floor panels that are under tiles, cladding for interior and exterior walls (wet area)
Composite materials are combination of two or more materials that individual materials can be distinguished (Newton, 2014). • Formation of a composite material (Newton, 2014): -combine with materials with different compositions -bond together -properties and identities are retained -have improved synergistic or specific properties by acting together
-Advantages: fireproofing, waterproofing, resistant to termite damage, warping and rotting, inexpensive
• 4 types of composite materials (Newton, 2014) -Fibrous material (contains continuous or discontinuous fibrres) -Laminar material (like sandwich panels) -Particulate material (for example, resins and gravel) -Hybrid material (combines with two or more types of composite materials)
-Common function: translucent/transparent cladding of roof/wall, preformed shaped constructing products like swimming pools, water tanks.
• Examples of composite materials
3. Aluminium sheet composites (Newton, 2014) -Ingredient: plastic and aluminium
1. Fibre Reinforced Cement (FRC) (Newton, 2014) -Ingredient: sand, water, cellulose fibres (or glass fibres), Portland cement
-Common forms: two exterior thin aluminium sheet with 53 a core plastic with made by phenolic resin
2. Fibreglass (Newton, 2014) -Ingredient: glass fibres, epoxy resins -Common forms: shaped/formed products, profiled and flat sheet products
-Advantage: fireproofing, weatherproofing, strong and light weight
-Common function: cladding material for exterior and interior use. Also used for window frames. -Advantages: inexpensive, lighter weight, weatherproofing, resistant to break and shock.
ďƒ˜ Construction Detailing
A joint sealant should be resilient, durable, adhesive and cohesive in order to offer an effective seal (Ching, 2008).
4. Timber Composites (Newton, 2014) -Made from: engineered timber, solid timber, galvanised pressed steel -Common function: beams, floor joists, roof joists, trusses -Advantages: efficient, cost effective, easy installation, easy accommodation services
Joint fillers, which are compressible and compatible, are designed to control the sealant depth without adhering to the sealant (Ching, 2008).
5. Fibre reinforced polymers -Made from: glass/carbon fibres, polymers/plastics with timber -Common formation: connected with moulded/pultrusion processed constructing products -Common function: external cladding; decking; structural element (beams & columns) for pedestrian bridges, combining with carbon/glass fibres
-Advantages: high-strength, strength-to-weight ratio higher than steel, corrosion-resistant
Generally, cove base is utilized as a trim and it is installed along the bottom of interior walls where interior walls meet floors (American Institute of Architects, 2007).
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The anchors were used to prevent the building from falling when the basement was digging.
Precast concrete panels were utilized because concrete expansion do not need to be considered.
The basement will be used as a car park and there will be a massive circulate machine for car lifting.
Diagonal proppings are used to support the concrete panel and they will be removed when the concrete panel is fully adhered (Ching, 2008).
Wet drainage system
• Lifting points were somewhere connected to the machine, and the precast column was lifted by the machine and moved into correct place. • It would be faster to construct by using precast column.
The concrete column is connected to a massive concrete pad underground. 55
Concrete Slab
Formwork
It is impossible to prevent concrete from expanding and cracking.
• The color of the timber section indicates the size of the timber beam. • The formwork will be removed when the concrete slab is fully adhered and strong enough. • The formwork is renewed and recycled.
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Lift
Reinforcement bar for concrete slab
This area is designed for bath, and the bath area is at the same place each floor, because it will be easy to install the mechanical service such as water pipes.
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References American Institute of Architects. (2007). Architectural graphic standards (7th ed.). New Jersey: John Wiley & Sons, Inc.,. Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey.
Newton, C. (Producer), & Newton, C. (Director). (2014). Constructing detailing. [Video/DVD] Melbourne: The University of Melbourne. Newton, C. (Producer), & Newton, C. (Director). (2014). Materials. [Video/DVD] Melbourne: The University of Melbourne.
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LogbooK Week10 Xiaodi Zhang 657695 59
Collapse & Failures Heros & Culprits (Hes, 2014)
Issues need to be considered in terms of selecting materials: • Health & IEQ • Waste/ recycling/ recycled • Energy use and embodied energy • Pollution • Life cycle Health (IEQ) Hero: oil based paint Villain: water based paint, glue, carpet (brings dusts) Source and waste Hero: -Bamboo---short-term to renew -Timber---recycled -Carpet---recycled -Fabric---recycled Energy --- embodied energy Hero: Timber---low embodied energy Villain: Aluminum products, light bulb
Pollution Hero: tiles, natural products Villain: PVC, cigarette/smoke
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A tale of corrosion (Newton, 2014) • Galvanic corrosion (copper skin + iron frame) • Copper Oxidization Could be removed by acid
dull
darker brown
green oxide patina
Copper reacts with oxygen • Solution1: Separating copper and iron at their junctions by a shellac-impregnated cloth layer (Newton, 2014).
Anodic End Magnesium Zinc Aluminium Structural Steels Cast Iron Lead Tin Copper, Brass, Bronze Nickel (Passive) Titanium Stainless steels
• Problem of solution 1: The cloth turns to porous over time and thus moisture is able to get into the joints (Newton, 2014). • Solution2: Replacing the iron frame by Tefloncoated stainless steel structure (Newton, 2014). Lateral Support
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• Wind forces are applied to the exposed surface to the wind (Newton, 2014). • Earthquake forces are applied to the building mass above the foundation (Newton, 2014).
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References Hes, D. (Producer), & Hes, D. (Director). (2014). Heros and villians - a framework for selecting materials. [Video/DVD] Melbourne: The University of Melbourne. Newton, C. (Producer), & Newton, C. (Director). (2014). A tale of corrosion - the statue of liberty. [Video/DVD] Melbourne: The University of Melbourne. Newton, C. (Producer), & Newton, C. (Director). (2014). Lateral support. [Video/DVD] Melbourne: The University of Melbourne.
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Appendix The workshop report (Date: 21/03/2014) Aim: To construct a structure withholding as much load as possible with 1000mm span. Material: • 1200*3.2*90mm Plywood*2 • 1200*42*18mm Pine*2 • Finishing nail • Roofing nail
Tools: • T Square • Back saw • Hammer • Measuring tape
Constructing processes:
• “Vertical” beams have more strength than “horizontal” beams. Thus, the pines in our structure were used vertically. • Two short beams were bonded between two long beams in order to reduce the changes of shapes under loads. 65
Structure
Material efficiency: • Ply timber is stretchy and it is good at bending, which has the advantage of supporting tension. Pine timber is more stiff than ply, which is beneficial to support compression. • When a vertical load is adding to the structure, the main structural action on the top is compression, while the dominant structural action on the bottom is tension. Therefore, we put pine timber on the top and ply timber on the bottom. 0 kg
Joint type: Pin joint was used in our structure as it is the easiest and quickest way to bond timbers.
220 kg
Structural performance: • The testing cradle was started with 0 kg with 40 cm, and our structure was destroyed by 285 kg with 45 cm. Thus, the applied failure load for the structure is 285kg and the maximum deflection is 5 cm. • The structure had no visible change when the load was under 200 kg. When the load was bigger than 200 kg, the pine beams began to bend vertically. 66 • By adding 273 kg vertical load, the pine timber was broken at the joint of pine and timber.
Failure mechanism: • The direction of the pine texture is horizontal. It will slightly destroy the horizontal texture of the timber’s inner structure when a nail is pinned into the timber. In addition, the inner structure will be destroyed more badly if nails are not pinned straightly. • In terms of our model, it was broken at one of the joints and the nail showed in the picture was not pinned straightly. Because of the incorrect joint way, there were tiny cracks inside the structure before the load was exerted, which gives rise of the breaking of the structure. • The structural performance indicated that the model would support more load if there was no problem of joints. • Another reason of the failure is that the pine timber could not hold the tension at the bottom, because the cracks were emerged from the bottom to the top. • Ply timber was used as beams. • The main force exerting on the top is compression and the main structural action on the bottom is tension. Ply timber is good Other group’s structural performance at supporting tension other than compression. As a consequence, the ply could not support the compression force and started to twist at the beginning. • In addition, the pine pieces did not make the model more stable. On the contrast, it reduced the bending capacity of the ply timber. 67
Tutor’s structure
• The structure was beneficial from the material efficiency as pine timber at the top is more capable to support compression and ply timber at the bottom is easier to hold tension. Additionally, the pines could separate the loads, which makes the model firmer.
• The applied failure load for this structure is 600 kg, and the maximum deflection is 5 cm. • There was no visible change of the shape under 300 kg load. When the applied load was bigger than 300 kg, the ply beams began to bend. Furthermore, as the load was added to 400 kg, the model began to extend horizontally. • When the applied load was bigger than 500 kg, the displayed figures from the testing cradle began to change abruptly.
• The structure was disassembled at the end. • The failure mechanism of this model was that the shapes of nails were changed under the loads, giving rise to fail to bond the materials.
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• Point load: A point load is a point bearing intense load or intense structural weight, and the load is transferred into the foundation (Ching, 2008). • Structural joints: roller joints + pin joints + fixed joints • Strip footing: Strip footings are utilized as loads from walls or series of columns is spread in a way of linear manner (Ching, 2008). • Pad footing (isolated footing): Pad footing has the function of spreading a point load to a larger area (Ching, 2008). • Substructure: The foundation part of a building which is below the ground (Ching, 2008). • Moment: A moment relates to the tendency of a force to make rotation about a point or along a line (Ching, 2008). M=F*d • Retaining wall: Retaining wall is designed to support lateral loads from soil as changes are made in ground elevation which surpasses the angle of the soil repose (Ching, 2008). • Girder: Girder is a reinforced concrete/steel/timber beam utilized as a core horizontal support (Ching, 2008). • Steel decking: Metal decking is designed as corrugated to improve its spanning capacity and stiffness (Ching, 2008). • Axial load: An axial load is parallel to the axis of the object, it may be caused by tension or compression (Ching, 2008). The axis of an object is a line that the object rotates along with. • Buckling: Bucking relates to a sudden torsional or lateral instability of a long, slender column (or other structural material) caused by the action of axial loads (Ching, 2008). 69
• Seasoned timber: Seasoned timber is stable timber material with less than 15% moisture content. • Eave: An eave is the bottom side of a roof which is exceeded beyond the external wall structure (Ching, 2008). Eaves are used to keep stormwater off external walls and adjust the solar heat of a building (Ching, 2008). • Soffit: Soffit is part of a ceiling that connects the top of exterior wall to the outer Side of the roof (Ching, 2008). A soffit covers the eave (Ching, 2008). • Portal frame: A portal frame is a low-rise structure, consisting of horizontal/ pitched rafters and column joined by moment-resistant connection (Ching, 2008). • Top chord: Top chord is the top beam of a truss (Ching, 2008). • Sandwich Panel: Aluminum composite panel
(Source: www.specialtydesign.com)
• Defect: Construction defect is relevant to the deficiency of design, construction and wrong materials (Ching, 2008). • Soft Storey: A soft storey building is a building with multiple floors which cannot resist lateral forces (Ching, 2008).
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Ching, F. 2008, Building Construction Illustrated, 4th edn, John Wiley&Sons, INC., Hoboken, New Jersey.
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