Constructing Journal - Week 4 - 6 Isaac X. Mercado - 636535
WEEK 4 - MATERIAL STRENGTH & COMPOSITE ACTION Overview of Materials: Interactive Structures - Module: Structural Materials (Metals, Concrete, Timbre) - Steel is coated for rusting - Encased for fire resistant - I beams, Universal Columns, Chanel Sections - Steel used for reinforcement concrete - Hydration process - Unreinforced concrete and reinforced concrete - Carry tension loads and compression loads - Module: Strengths of Materials Module - Compression, Tension, Shear - Stress - Relationship between force and area
Composite Actions: - Monolithic - Single material or materials combined so components are indistinguishable - Eg. Alloys - Composite - Two or more materials combined in such a way that the individual materials are easily distinguishable - 1. Combination of materials which differ in composition or form - 2. Remain bonded together - 3. Retain their identities and properties - 4. Act in concert to provide improved specific or synergistic characteristics not obtainable by any of the original components acting along. - Hard to distinguish - Types - Fibrous - Discontinuous or continuous fibres - Laminar - Sandwich panels - Particulate - Gravel and resins
- Hybrid - Mixture of two or more of the above - Fibre reinforced concrete - Cement sheeting - Fibre glass - Surf boards - Aluminium Composites - Resists tarnishing - Insulation - Bent, turned and fixed on exterior of buildings - Floor beams/trusses - Fibre reinforced plastic
Materials: Concrete - Takes shape of its mould - Guggenheim (Frank Lloyd Wright) - Concrete frames - Palazzetto dello Sport - Concrete - Cement - Fine aggregate (sand) - Course aggregate (crushed rocks) - Water - Laying Concrete - Formwork - Pour concrete - Screeding (spread and make even) - Smooth Finish with tools - Curved edges, reduces chipping - Finish (textures) - When concrete is first missed it is plastic before it hydrates and hardens into a solid mass - Hardened state - Strong durable - High density - Hard
- High compression strength - Weak tensile strength - High embodied energy - Low toxicity - High porosity in aerated concrete - Flammability (excellent fire resistance levels) - Reinforced concrete created from plant pots - Waffle slab - In situ - Poured on site - Reinforced columns - Precast panels - Different finishes - Water penetration, structural integrity was compromised
The Pantheon - Atypical building in Roman Architecture - Required different typology - Temple architecture, Hellenic influences - Influenced by Parthenon - Rectangular building - Singular room - Circular room - Niches and indentations in walls - 3 main elements - Portico - Courtyard - Deceive the viewer - Drum - Obscured view - Brick face concrete - 6.15m thick - Lateral forces - Brick face concrete - Hemispherical dome - 43.2m in diameter - Largest span concrete shell dome - Top half of the sphere - How constructed - Based on acuate
- Based on arch - Used only compressive forces - Vault - Colosseum, Rome - Lateral vaulting - Roman concrete - Large stones/rocks (aggregate) - Pattern on face defines type of concrete - Pots Alana, concrete set regardless of water evident - How they made the dome - Thickness at top of dome is 1.5m thick - Spread force down onto walls - Range of aggregate forms in concrete in various sections - Lighter rocks as the dome gets higher - Opening at peak - Symbol of power
Figure 2: Sectional of The Pantheon Source: http://www.lib-art.com/imgpainting/0/7/2970-the-pantheon-inrome-antonio-lafreri.jpg
Figure 1: Inside The Pantheon Source: http://theproegers.com/wp-content/uploads/2012/02/Pantheon-Rom.jpg
WEEK 4 - STRUCTURAL DRAWING ANAYLSIS MSLE Extension to Building:
MSLE Extention to Building
soil Brick rendering
cement Floor Truss - cement
WEEK 5 - FLOORING SYSTEMS Ching:
Materials: Timber
- Depth of the floor system has a direct correlation of all the dead loads that will be constructed - Span, distance from one support to the other support - Beams and columns - Spacing and span - Floorboard - 19-25mm thick - Plywood - Span divide by 30 to figure out thickness of slab - One way slab - Two Way Slab - Waffle Slab - In Situ & prefrabricated - I Beams, C Beams, Rectangular Hollow Section (Structural Tubing) - Open Web Joist - Pass services through them - 422 – Steel decking and then concrete in poured over it - Joist and Bearers - 450mm-600mm - Single, double, continuous spans
- Each type of timbre has different properties - Layers - Heartwood - Not used for structural purposes - Sapwood - Cambium Cell Layer - Inner Bark - Outer Bark - Finger Joints - Grains in timbre - Strong parallel to grain - Weak perpendicular to the grain - Knots - Weakness on timbre - Quarter Sawn
Figure 3: PosiStrut Floor Joists
- Make timbre strong, get rid of moisture - Back Sawn - Seasoning - Want to get moisture content same as inside building - Strengthens timbre - Air, Kiln, Solar (Types of drying) - Fully Seasons - Less than 15% of its original water content - Soft woods - Pines - Hard woods - Ash - Brown Box - JaraJara - Appearance - Utility - Structural
- Downsizes - Decay - Weathering - Chemical - Fire - Fungi - Termites - Major enemy is water - Standard depths and breadths - Length 300mm – 600mm - Laminated Veneer Lumber - Deep and long sections that are very strong - Plywood - Laminating this veneers together in different directions - Expansion and contraction - Bracing of timbre frame - Cross Laminated Timbre - Cheaper footing - Solid structural wood
Figure 4: Timber Stud Wall
WEEK 5 - STRUCTURAL CONCEPTS MSLE Extension to Building:
Existing Steel Reinforced Concrete Slab
Flooring System
Pad Footing System - Brick Columns - Steel Reinforced Concrete Base
Roofing System
Wall System Brick Wall
Universal Beam
PFC Steel Beam
Cement Wall
Flooring System
Wall System
Roofing System
WEEK 5 - PRESENTATION Structural System:
WEEK 5 - PRESENTATION Structural Materials & Joints:
WEEK 5 - PRESENTATION Different Fixings:
WEEK 5 - PRESENTATION
Economic & Environmental Factors:
WEEK 6 - COLUMNS, GRIDS & WALL SYSTEMS Wall Systems:
Materials: Metals
- Transfer down to foundations - High fire resistance - Masonry, concrete - Air sound and moisture - Where one material meets another - Walls maybe load bearing or non-load bearing - Needs to allow services - Lintels - Carry loads across into adjacent walls - Angle lintel (L – Shaped) - Concrete, Steel and Timbre frames - City column and slab(mostly uses concrete) - Most aussie houses uses stud walls - Brick veneer construction - Concrete Section - Grid used a lot - Waffle slab - Concrete - Precast or insitu - Formwork - Precast Concrete - Common in commercial - Masters & Bunning near South Morang - Craned into site - Mitre – 45 degree - Butt Joints – 90 degree Figure 5: Concrete Process - Expansion joints - Breaks in concrete and provides space for contraction - Stretcher Bond - Steel Grid system - W shaped or I beam - Columns and beams primary structure (Universal Columns) - Girts
- Ironbridge - First cast iron bridge in UK - Australian Centre for Contemporary Art - Rust, decorative finish - Guggenheim Museum, Spain - Frank Gehry - Randomness of the curves used to capture light - What is metal? - Ductility, malleability, brittleness - Ferrous metals (contains irons) - Metallic lustre - Thermal Conductivity - Electrical conductivity - Very dense - Alloys - Mixture of metals - Different melting point - Iron - Predates steel - Wrought Iron - Horse shoes Figure 6: Galvanised Steel Bracing - Cast Iron - Melted and poured - Typically alloyed with carbon - Aluminium - 20th century - Frames - Window frames - Smooth walls and mirrored glass - Extruded, rolled or cast Figure 7:Aluminium T-Runner - Cladding panels, sandwich panals - Copper - Electrical, second to silver
- Zinc
- Stainless Steel - Surface cladding on steel - Hand rails - Galvanising - Nuts and bolts - Alloy zinc and aluminium - Chrysler Building - Lead - Bronze - Flashing - Older buildings - Roofing - First copper alloy - Poisonous to humans - Corrosion - Tin - Rust - Historically used, now not so much anymore - Iron needs Air and Water to corrode - Nickel - Galvanic Serise - Used as an alloy - Anodic End (more prone to corrosion) to Cathodic End - Component in stainless steel - Rules of thumb - Doesn’t corrode - Select metal appropriate for environment Figure 8: Types of Reinforcement - Alloys - Avoid damp conditions - 1740 – iron combined with carbon - Insulate between metals to avoid conductivity - carbon changed, different types of steel made - Further apart. Larger reacton - Steel - Different metals in flowing water, water can flow down the scale - Strong, high tensile but not up - Composition - Serious corrosion if anode is small - Iron Ore - Corrosion increases with heat and sulphates or chlorides - Coke - Galvanic Corrosion - Flux - Statue of Liberty - Molten Iron - New Teflon covered steel - Scrap Steel - Coatings and Preservative Methods - Reinforcement - Painting or laquering - Zincalume coated steel roofing - Electroplating - Galvanised steel purlins - Zincalume Coating - Walling material - Galvanising - Hot rolled sections - Joining methods - Strong - Mechanical - For heavy loads - Nuts, bolts, metal screws, rivets Figure 9: Steel Reinforced Pot - Heat strengthens the steal - Soldiering and brazing - Cold Formed Steel - Welding - Lighter construction - Secondary structure - Eg. Girts Figure 10: Types of Beams
WEEK 6 - UNDERSTANDING STRUCTURAL SYSTEM MSLE Extension to Building - Construction Process
We first started with the walling system. Using the cardboard we created the two external wall that the majority of the connect is built upon. The right side is a steel reinforced concrete wall and the left side is a load bearing brick wall.
The back end contains a lift/elevator and this utilises a combination of steel reinforced concrete as well as fixed glass panels
For the flooring system, we used a combination of wooden strips to represent the various types of beams as well as cardboard sheeting to indicate the flooring used such as vinyl and timber decking. The front section also indicates the lower roof level.
We used some cardboard sheeting to exemplify the Colorbond Kliplock Roof Sheeting.
Along the exterior, a conbination of fixed glass windows are located around the windows. Steel lintels were utilised to help support the loads above the windows.
For the roofing system we used carboard strips to represent the different element. The sheeting contains a slit that represents the Box Gutter.
WEEK 6 - UNDERSTANDING STRUCTURAL SYSTEM MSLE Extension to Building: Load Bearing Brick Wall
Steel Reinforced Concrete Wall PFC Steel Beam
Load Paths: UB Steel Beam
External Loads Load Paths
Timber Floor Joist
Steel Reinforced Concrete Floor Slab Colorbond Kilplock Roofsheeting C Purlins
Steel Rafters
Aluminium T-Runners *connected to C Purlins
Steel Angular Bars
Stud Wall
As the external walls are made of strong steel reinforced concrete, wind loads would be deflected off the building. A lot of the external loads would be carried down along the load bearing brick wall and steel reinforced concrete wall and ending at the foundation.
Vertical loads that fall along the roofing system would be carried down to the rafters and transferred horizontally to the two walling systems. The first floor system would utilise the PFC & UB beams to transfer the loads to the walls and down to the foundation.
WEEK 6 - TIMBER WORKSHOP designing: aim:
To construct the strongest structure, with the materials and equipment provided, that spans over 1m long. The structure would be tested under a point load.
As we brain stormed some ideas, our initial thought was to utilise the high compressive strength that the plywood contains along it’s thinner face. However, we needed to stabilize the lateral movement of the plywood. The shape which presented itself represents that of an ‘I’ beam, which is quite commonly used as a supporting element. We decided that it was much too difficult to create a slit on the pinewood to stabilize the plywood.
materials:
- 1200mm x 35mm x 35mm - Pine Wood - screws - 1200mm x 3.5mm x 90mm - Plywood - nails
Another structural concept, which we played around with involved creating a series of trusses that would help, spread the load across the whole structure. We felt that this was quite strong however; having the precision necessary to construct this would be much too difficult with the lack of the materials and minimal time. Each truss would need to be the same length but also the same angle to ensure that the load would be spread evenly. We would then use plywood as a bracing, similar to that of a stud wall in a home.
With the three pieces of pinewood, we decided that the least amount of cutting and joinery on pieces would help sustain its structural strength. By stacking the pieces of pinewood together, it would increase its compression strength along the top of the structure as well as directly increasing its tensile strength along the base of the structure.
WEEK 6 - TIMBER WORKSHOP constructing:
We chose to nail the three pieces together on either end, as the nails would only create a weakness in the wood. The point load would then not allow any splitting of the wood along these nailed points.
To help brace the three pieces of pinewood together in the centre, we chose to split the plywood in two and use it as bracings. We chose use screws as their provided a much more rigid connection due to the grooves in the screw. We knew that the screws would create some point’s weakness in the structure and tried to focus them toward the top of the plywood to provide extra compressive strength to the plywood. However, we felt that by reducing the amount on the bottom face of the plywood we were not able to brace the three pinewood planks adequately together.
Truss Structure Other groups tried to utilise the truss structure but failed quite quickly as their joints were not secrue and the load did not spread evenly. Another structure utilised the plywoods vertical strenght, however, it failed as the plywood did not take the point load well.
Our main point of failure was along these screws that we used on the plywood. They created points of weakness, especially where the screw vertically lined up. The main crack along the centre had a couple of screws that lined up. We found that the excessive use of screws along the bottom of the plywood decreased the tensile strength and split the plywood and pinewood much more quickly.
WEEK 6 - TIMBER WORKSHOP testing:
Start Point:
Position 2:
Position 3:
Load: 0kg Deflection: 0mm
Load: 60kg Deflection: 0 - 5mm
Position 4:
Position 5:
Load: 100kg+ Deflection: 5 - 10mm * First sounds of cracking
Load: 500kg Deflection: 10 - 20mm
Load: 650kg Deflection: 10 - 15mm
Position 7:
Final Break: * Indications of sections where failure is occuring and the load begins to decrease as the structure has altered from original state
Load: 750 - 800kg Deflection: 20mm
Position 6:
Load: 700kg Deflection: 15- 20mm
* Clean break occured and it snaped through all three pieces of Pinewood. There was a clear vertical crack through all three indicating that one of the screws created a line of failure.
GLOSSARY WORDS:
WEEK 4
WEEK 4
WEEK 5
WEEK 5
WEEK 6
WEEK 6