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CONSTRUCTING ENVIRONMENTS -

How to design ideas and translate to built form Structural principles and material properties How the built environment works Basic science principles Systems Standard construction techniques

Theatre Session 01 – Form : Folding paper to support a brick

TOPIC: INTRO TO CONSTRUCTION

Live Loads Wind loads kinetic energy moving mass of STRUCTURAL C ONCEPTS: LOADS AND FORCES air (horizontal direction) positive pressure exerted Tension Forces horizontally on vertical surfaces and normal of surface slanted When an external load pulls a O >30 structural member. negative pressure/suction on particles move further apart, Ching, Building Construction building sides, leeward and to causing elongation O Illustrated, p. 2.09 normal of roof surface <30 particles undergo tension flutter: rapid oscillations of flexible cable/membrane material becomes ‘longer’ structure caused by aerodynamic effects of wind thermal stresses: material structures susceptible to flutter (tall, slender, unusual, constrained against expansion complex shapes and lightweight flexible structures require wind tunnel testing computer modeling done to investigate response to Compression Forces distribution of wind pressure When an external load pushes a structural member, particles move closer together material becomes shorter thermal stresses: material constraint against contraction Earthquake Loads (dynamic load) Longitudinal and transverse vibrations induced by tectonic Torsional Forces plates abrupt movements Stiff structures: oscillate rapidly, When a twisting force is applied on short periods a structural member (one or both Flexible structures: oscillate ends twisted in opposing slower, longer periods directions)

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particles move about their fixed orientation where another particle revolves around the bond ßChing, Building Construction Illustrated, p. 2.10

Load Path Diagrams -

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Name:

Lai Yoong Yen

Student ID: 676916

visually explores how loads of objects are distributed throughout structure movement of forces in a member are very important the difference between being stable or falling over notation of forces with arrows reaction forces considered to rd maintain Newton’s 3 Law (every force has an equal and opposite reaction) ENVS 10003: Constructing Environments

Loads on buildings Water pressure: hydraulic force groundwater exerts on foundation system Occupancy loads (live loads), from furniture, people, etc Snow and rain (live loads) can add to the roof’s dead load if they accumulate - roof needs to withstand structural weight as well as added weight

Arrows represent direction forces act

A01 – Logbook

Week: 1

Page: 1


CONSTRUCTION SYSTEMS 3 types 1. 2. 3.

of structures Column + Beam Mass Construction Tensile Structures

     

 

Column + Beam -

Sopher, C. (2014). Brick Wall on Cornerstone Building. Peoria, Illinois: Chris Sopher.

LARGE MODULAR MASS CONSTRUCTION

MATERIALS PROPERTIES:

UB = universal beam UC = universal columntypically used as supports for walls and roofs beams usually lay horizontally whilst columns stand vertically web and flange of universal beam/column each have their own purpose, where the web (the depth) withstands sheer load and the flange is strong enough to resist bending and stop rotation

Mass Construction using mass of material to transfer weight to foundations can be small modular mass construction (SMMC) or large mass modular construction (LMMC) common form of mass construction is masonry, of which there are many types (mud/clay, concrete, etc). method of construction can effect material mass distribution through to the foundations, as shown in brick laying patterns Tensile Structures entire structure is under tension, without and bending or compression forces acting on the structure tent like structure is usually supported by suspension cables or some sort of post very different form than mass and column/beam construction typically freeform styled shapes roofing can be a waterproof fabric (ie: Olympic Stadium, London Olympic Park) which is lightweight and cost effective (in terms of transport and construction, the construction is easier to manage than tonnes worth of concrete

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1. Strength - how much force can it withstand in any given direction 2. Stiffness - how rigid/floppy/stiff the material is (stud frame construction where wood walls used in houses are nailed to increase their rigidity) 3. Shape i. mono dimensional (linear) ii. bi dimensional (planar) iii. tridimensional (volumetric) 4. Material behaviour - isotropic or anisotrophic 5. Economy and Sustainability - how expensive, abundant, readily available a material is, and how its extraction or manufacturing impacts the environment in the short and long term

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Lai Yoong Yen

Student ID: 676916

i. Mud/clay Method 1: Extrusion Length of clay is extruded and pushed through a die (a former), then cut into individual bricks and fired in kiln. Less material used during manufacture (holes running through body), therefore cheap and lightweight.

- Small module i. Mud/clay   ii. Concrete blocks - Large module i. Precast concrete Concrete: not good under tension, must be reinforced with steel stainless/galvanised steel used in severe conditions, to protect against the elements present in concrete composed of aggregate (terrazzo, rock, sand), water, cement Clay soil with many minerals, a natural resource from earth used for construction as well as decoration bricks previously made by hand, now machine processed for mass production

Method 2: Press bricks Brick is made by a former pressing clay/mud into shape. Bricks are made individually, and features a ‘frog’ (crevice to allow thickening of mortar to bond bricks together)

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ENVS 10003: Constructing Environments

Advantages cheaper than a SMMC block less labour involved, because it is mostly machine operated pre-made off site in a factory, allowing processes to run simultaneously on and off site, thus compacting construction activity over given period of time (less running costs) quality control is instilled if there is any detailing needed Disadvantages unloading requires cranes each block has a 10 tonne load limit (before specialist machinery is required to move blocks

SMALL MODULAR MASS CONSTRUCTION

Masonry

Name:

i. Pre-cast Concrete large panels of concrete prefabricated in a mold and transported to construction site for construction

Advantages does not warp, erode or fade (weather resistant) retention of heat (thermal mass) fire resistant various finishes and applications (design flexibility) Disadvantages uneven heat distribution whilst fired in oven causes uneven strength throughout brick (less heat exposure makes brick paler in colour and brittle). Will look and function differently structures limited in height (the taller it becomes the thicker the walls required to distribute mass and maintain structural integrity) structure height limitation due to unsafe scaffold heights ii. Concrete blocks Advantages decorative (patterns and intricate designs can be worked) high level of detail is achievable Disadvantages slow process brittle and more likely to break during small drops on site.

A01 – Logbook

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Mass Construction Tower!

A tiered building where each tier gradually recedes into the building, which could ideally fulfil the objective.! A lot of blocks would be used in the construction of this structure. In a life sized structure, majority of the bricks will add extra weight and cost to the building. However, the bricks in the core will be needed to support the upper tiers, unless columns and beams were used, but this is not the aim for this objective. The platform on the top may be large enough to support the dinosaur but there will be no thoroughfare to pass the dinosaur through.!

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Objective: build a mass construction tower to withstand the weight of a toy dinosaur without toppling over, and allow it to pass through the structure.!

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- using as few bricks as possible! - 1 brick can be removed without the structure collapsing! Each brick is made of MDF and all of equal size. Being a lightweight material and appropriate size, a variety of designs can be possible for the building.!

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Design 3 (chosen design):!

With a dense structure, brick laying will have a tendency to be sporadic because of the simple structure.! Removing one brick from the structure is not only difficult, but also reduces the structure stability.Therefore, this design is inappropriate.!

Influenced by the Arc De Triomphe, Paris, France, design 3 holds as a better alternative to fulfil all parts of the objective. Being a monolithic structure where compression is the main action of which the materials are under, arches could be beneficial in stability provided a suitable brick pattern is instilled.!

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Improvements:! Reduce the number of blocks used - also minimise the structure width and depth

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A half basket weave bond or compact running bond would be prospective patterns to use. The overall structure will taper off from the sides in a triangular form, unlike the Arc De Triomphe which is more rectangular. 2 side by side half basket weaves will make up the width of the tower, which should be strong enough because of the distribution of mass (heather brick which is perpendicular to other brick increases stability).!

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Design 2:! Bricks are laid in a circular pattern (suggested to be 200mm in diameter in order to facilitate the toy dinosaur and meet the objective) with spaced left between each brick. A large circular space in the middle will allow the toy dinosaur to be placed in the middle. fulfilling part of the objective. However there will be difficulty building a platform on the top for the dinosaur to be set on. The toy may be balanced on one of the top bricks but stability will be an issue.!

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With triangulation, the top of the tower will be able to support the dinosaur but stability is questionable

Fewer blocks will be used in this structure than that used in the first design. Construction time should technically be shorter (due to less material being involved per level) but with gaps between each brick, careful placement of each individual brick needs to be done so that each brick is supporting each other (a broken up form of running bond)!

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Improvements:! The gaps between each brick will not be equal to one another as the brick laying will be done within a short amount of time given (1.5 hours), thus the structure will suffer as it gets built higher. Find a method to reduce the number of bricks necessary AND maintain the stability of the structure as a whole! The structure walls are only 1 brick thick, explore making the walls more than 1 brick thick to increase stability of mass structure.

Student Name: Lai Yoong Yen!

Dead loads! - stationary and unmoving loads where their weight acts downward on the surface it rests on! - examples: !

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Live loads! - applied suddenly to a structure where there are rapid changes in point of application and magnitude (Ching, 2011)! - examples: wind, seismic!

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Load path diagram! - a diagram where arrows dictate the direction of which the force from a load is distributed through a structure. Reaction forces are also considered.!

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Compression! - when an external load presses the member and causes the particles to move closer together!

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Tension! - when an external load pulls a structural member and material particles move further apart! Reaction force!

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Forces and Scale! - forces are a vector quantity where they have magnitude and direction. Magnitude and direction can be represented by the size and scale of an arrow!

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In the big picture, this structure design is not completely appropriate but does partially fulfil the brief. The compression of each brick one on top of the other is too great to the point that if one brick is removed from the structure, there is a great weak point because every brick above it would have less support.!

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Subject Glossary:!

Design 1:!

UB - Universal Beam! UC - Universal Column! PFC - Parallel Flange Channel! CHS - Cylindrical Hollow Section! SHS - Square Hollow Section! RHC - Rectangle Hollow Section!

A bent piece of card was used as a former to support the arch in the early stages of construction

Student ID: 676916! !

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A close up look of the brick laying pattern. Heathering is used to distribute the weight over a broad base

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ENVS 10003 : Constructing Environments! !

Testing: structure was sturdy, enabling the dinosaur to balance on the pinnacle as well as pass through without difficulty. When removing one brick, it was fairly difficult due to the wall thickness and tight due to mass of bricks above acting on it. Towards the pinnacle, brick laying had to change in order to maintain balance, by using a 3 by 3 brick pattern

Week : 1!

Page 3


Theatre Session 02 – Water tankard : Establishing joints to a model

TOPIC: STRUCTURAL LOADS AND FORCES

Structural Connections (Ching, ‘Building Construction Illustrated, p2.25-2.26)

Roller Joint - Allows rotation - Resists translation in direction perpendicular into/away from faces - Not applied in building construction - Useful when joint must allow expansion an contraction of a structural element - Example: cable anchorage

STRUCTURAL C ONCEPTS Structural systems 1.

       

Solid systems (Ching, ‘Building Construction Illustrated, p2.25-2.26)

Wilson, K. (2012). Colosseum Arches.

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Main structural action: compression (axial) Common system in early structures, eg: Colosseum Typically made of mud, bricks, mud, creating monolithic forms Arches become efficient structural feature (use of keystones and relieving arches, as used in the Colosseum) Shell/Surface systems

Pin Joints (construction industry) - Useful for engineers making calculations and assumptions in how system behaves (used in truss systems) - Example: cantilevers, crane bracing joins

(Ching, ‘Building Construction Illustrated, p2.27)

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Moore, D. (1966). Opera House roof geometry.

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Transmits applied forces by membrane stresses in plane of surface (compressive, tensile, shear) Constructed of reinforced concrete Thin: has little bending resistance Eg: Sydney Opera House Frame/Skeletal Main structural action: Common form of structural system Efficeint way of transferring loads into ground Eg: Eiffel Tower Membrane systems (tension)

Fixed Joints - Complex - bending can occur if a load happens in one member, it can cause bending at joint - Example: crane connected to base slab

(Ching, ‘Building Construction Illustrated, p2.29) Calatrava, S. (20122014). World Trade Centre Transportation Hub.

Ching, F. D. K. (2008). Membrane Structures Building Construction Illustrated (pp. 2.29).

Name:

Lai Yoong Yen

Student ID: 676916

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Main structural action: tension Efficient coverage over large area for low cost A form of thin-shell structure Eg: sails, sports stadiums Hybrid frame clad in membrane mixture of skeletal and planar systems pneumatic structure, air integral to maintaining structural integrity of building ETFE (Ethylene tetrafluoroethylene), good coverage over large expanse: efficient and cheap. Eg: Beijing Olympic Stadium

ENVS 10003: Constructing Environments

A01 – Logbook

Week: 2

Page: 4


CONSTRUCTION SYSTEMS

Construction processes Decisions on construction system in terms of following criteria:

System: assembly of interrelated/interdependent parts forming a more complex and unified whole, serving a common purpose

Performance requirements: Taller buildings will require higher fire resistance in order for occupants to have time to leave building Fire resistance, prevention and safety, structural compatibility Regular fire constraints apply for buildings, especially on the height of the building Control of heat and wind through building Comfort (insulating, double glazed windows, breezes) Noise reduction, sound isolation and acoustical privacy

Construction systems Definition, scale, proportion, organisation of interior spaces Human activities relative to size and their dimension Horizontal and vertical access through interior spaces An integrated component of built and natural environment (Ching, 2008)

Name:

Lai Yoong Yen

Structural System

Enclosure System

Primary member: Spans over shortest length for support. Main load carrying member Eg: columns Secondary member: Carries load to primary member Eg: purlins, beams, portal frames Tertiary member:: Transfers loads to secondary members

Student ID: 676916

Regulatory Constraints: Materials and construction methods selected based on function and regulation. Eg: kitchens and hospitals require certain kinds of finishes that don’t retain bacteria (impervious, high polish finishes) Aesthetic decisions to comply with zoning ordinances, building codes and overlays Working within building budget Constructional context from climates to countries, available materials and labour Environmental Impact: Economic considerations (material longevity, resistance to wear, corrosion and weathering) Energy efficiency of mechanical systems (how well building performs as filter to reduce usage of air-conditioning, heating, lights, etc) Economic Considerations: Initial cost: materials, transportation, equipment, labour Life cycle, maintenance, operation, renovation and demolition costs Energy consumption, percentage of useful lifetime Cost and planning of building components either in-situ or prefabricated, and transporting them from factory to site, etc.

Mechanical System

Enclosure System: Shell/envelope to encase structural system, consisting of roof, exterior walls, windows and doors Roof and exterior walls provide shelter from weather and control warmth, moisture and air flow through layering of construction assembles Exteriors and walls dampen noise and provide security and privacy for occupants Doors allow access to interior spaces, windows allow light entry, and interior walls and partitions subdivide the space Structural System: Designed and constructed to support and transmit gravity and lateral loads safely to the ground Columns, beams and load bearing walls support floor and roof structures Superstructure: vertical extension of of building above foundation Substructure: underlying structure forming foundation of building Mechanical (Service) System: Provides essential services to building Water supply provides water for human consumption and sanitation Sewage disposal system removes fluid waste and organic matter away from building Heating, ventilation and air-conditioning condition space for comfortable human environment Electrical systems protect and distribute power safely around building for power, lighting and security Fire fighting systems detect and extinguish fires

Aesthetic qualities: Desired relationship of building its site, adjacent properties and neighbourhoods (decision of materials to use) Preferred qualities of form, massing, colour, pattern, texture and detail and be easy to maintain

(Ching, ‘Building Construction Illustrated, p4.15) (Ching, ‘Building Construction Illustrated, p2.03)

ENVS 10003: Constructing Environments

Construction practices: Occupational health and safety requirements Allowable tolerances and appropriate fit, considering available and cost-efficient transportation methods Building budget constraints (inclusive of allowance funds for delays) Construction equipment requirements Provisions for unexpected and rough weather A01 – Logbook

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Subject Glossary:! Force Any influence that produces a change shape or movement of a body A vector quantity (with magnitude and direction) An arrow where length is proportional to magnitude and orientation is direction

Balsa wood Tower! Objective: using only the piece of balsa wood given (150mm x 700mm x 5mm), construct a tower tall enough to touch the ceiling (roughly 3600mm = 12 feet) Design:! Design follows a tiered nature where the bases get intermittently smaller to a spire. A spire coming out from the top can gain more height from the sturdy base. However, the longer the spire, the more flexible it will be.!

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Tension Material is pulled outwards by a force where particles are moving away from one another Stretches material

From structural joints used in life sized structures, bracing would be needed (as shown by cell towers). However due to the limited amount of material at hand, bracing can’t be considered as this requires more material than available.

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Compression Material undergoes a force acting inward, causing particles to move closer together ‘Shortens’ material

Modelling:! Modelling was done with cardboard from a shoebox, which posses similar characteristics to the plywood (relatively bendy, easy to cut, same material thickness).!

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Structural Joint joint which performs as a structural member (upholds load effectively)

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Stability a point of equilibrium and rest is achieved all forces (applied and reaction) are balanced

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Frame ‘skeleton’ of an object/body the main structure in a hybrid system Bracing Column a support (diagonal, horizontal, vertical) that interconnects with part of main structure to hold in place

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Solid Systems Typically used in early age buildings Materials: stone, brick or mud (compression structure) Arches were deemed highly efficient because of the compression mass structure

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Scale is a problem with this model where the mass to size ratio won’t necessarily apply to the real, larger structure.

Making! Having followed the plans, improvisation was needed after the first level was constructed because it was found that the balsa wood was bending too much from its own weight. As a result, bracing was done to increase the frame rigidity. Material was obtained from previously built structures around the room - even though the tower eventually reached the roof, extra material was used to aid the achievement. Testing:! The tower was unable to withstand low load forces such as light wind due to it’s frail and imbalanced nature.!

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“Less is more” applies heavily to this tower, where there is fewer components interacting. Building Management! - carbon footprint - amount of greenhouse gases created during fabrication and usage of partial product! - green building solutions reduce energy usage substantially! - reduces embodied energy going into construction and operation!

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ESD - Environmental Sustainable Design! - Orientation (windows facing North/South protection from higher up summer sun but access for winter sun)! - water harvesting (rain water harvesting for irrigation and toilet flushing)! - night air purging ! - forcing out hot air and replacing it with cooler air through floor louvers (ventilation to moderate temperature)! - thermal mass - release of retained heat in material dissipated! -solar energy (using heat from the sun rays to heat up water

Thinner splints used in bracing snapped easily during testing, suggesting that the material and system was not as effective as planned.

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Evaluation:! From the photographs on the left, the tower started to twist and buckle as it was built upwards. The tower was unsuccessful in the case of stability and endurance. Bracing was inconsistent (in brace thickness and positioning), thus being the main cause for twisting. For future efforts, it’s suggested that each piece of balsa wood is to be cut into equal dimensions and bracing to be evenly distributed.

Frame Systems Efficient way of transferring load to ground Membrane Systems Less common, but also quiet useful Hybrid Systems frame system then covered with membrane system(mostly aesthetic rather than functional)

Student Name: Lai Yoong Yen!

Evaluation (part II)! Another tower of similar stature used more balsa wood than provided however, their method of construction is much more conducive in the sense that the bracing is much larger.! Smaller bracing accusatively requires more material, meaning that each brace is thinner. Longer brace pieces would strengthen the structure, keeping it upright and reducing twisting in places.!

Student ID: 676916! !

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If we increase the beam length, we must increase the DEPTH - self weight eventually can’t withstand the load

Until a certain point, no matter how much we increase the depth as the length stretches onwards, eventually the beam will break because of it’s self weight. By cutting out holes in the body (removing excess material that aren’t being used), the length can extend a little longer

ENVS 10003 : Constructing Environments! !

Week : 2!

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Theatre Session 03 – Case Study #1 : London Olympic Park (now Queen Elizabeth Olympic Park)

TOPIC: FOOTINGS AND FOUNDATIONS NORD. (2012). Primary Substation 2012 Olympics

 

STRUCTURAL CONCEPTS Geometry

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Centre of mass – point object is balanced, and entire weight of the object is concentrated

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Equilibrium State of balance/rest, where equal action of opposing forces Moments - Tendency to make object/point rotate due to applied force Free body diagram F x d (along line of action that does not pass through point) Applied forces (F) and reaction forces (R) represented by arrows To be in equilibrium, ΣF + ΣR = 0 No rotation, ΣMoments = O Not moving up or down, ΣVertical Forces = 0 Not moving left or right, ΣHorizontal Forces = 0 Has magnitude and sense Nm or kNm (Newton meters)

Hunt, T. (2003). Structural elements and element behaviour Tony Hunt's Structures Notebook (pp. 41). Name:

Lai Yoong Yen

Student ID: 676916

ENVS 10003: Constructing Environments

A01 – Logbook

Week: 3

Page: 7


CONSTRUCTION SYSTEMS

Structural Elements

Mass and Masonry materials

Design based on loads to be carrie, materials used and form/shape

Footing and foundation designed to ensure settlement occurs evenly (bearing capacity of soil not exceeded) -

Bearers

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Strut - member in compression under load - typically a column - can buckle if not internally stablised

Tie - in tension - extend under load

Under tension – tendency to change shape (deflection)

Slab/Plate - Weight transferred into beams - 2 way support system

Name:

Beam Materials need to support compression and tension Timber, steel, reinforced concrete Reconstructed to be structurally sound Deflection due to bending

Wall/Panels Shear diaphragm Deep vertical element designed to carry vertical or horizontal load Precast building Deform due to inplane load Particles of material slide relative to one another

Load transfers through

Lai Yoong Yen

MATERIALS

Student ID: 676916

Settlement is compressing the earth beneath, causing building to sink into earth Cracking in building caused by differential settlement (uneven) if superstructure load too great for soil strength, footing will sing

Footings Types of shallow footing - Use: houses (light weight), unless over an old quarry Pad footing Spread point load over larger area of ground Strip footing Loads from walls/series of columns spread in linear manner Raft foundation Provides increased stability by joining individual strips together as single mat Slab thickenin in middle to increase Stiffening through several layers to stop warping -

Types of deep footing Use: high rise buildings, heavy buildings Driving long timber/steel/concrete members into ground Drilling into ground then filling with concrete (steel reinforcement cages) End bearing piles Extend foundations down to rock/soil to provide support for building loads Friction piles Rely on resistance of surrounding earth to support structure

Foundations Substructure of building to transfer loads acting on building into the ground

Mass (monolithic) Stone (slabs, rubble, asher) Earth (mud, brick, adobe) Clay (brick, honeycomb block) Concrete (blocks, commons – smaller than blocks) Strong in compression, weak in tension. Units act together as monolithic whole. Masonry Stone Clay Concrete Building with units of various natural and manufactured products (joined by mortar (bonding agent) -

Concrete shrinks (contracts) à contraction joint Brick expands à expansion joint

BRICK Brick: dense, semi-permeable, reusable, fragile, hard (only scratched with metal objects, brittle, durable, low plasticity. Varying colour à varying heat exposure à varying energy content -

Advantages Joined with water based mortar, low cost additive If adequately ventilated, won’t deteriorate Disadvantages Porous in long term water presence, will absorb moisture and expand over time, expansion joints will be required Salts and lime from soil drawn through brick when in contact with ground (efflorescence)

Bond – Unit pattern Course Types of foundations: horizontal Shallow footings: running row Stable soil conditions (required bearing capacity and close to Joint surface) - way units are Load is transferred vertically from foundation to ground connected Deep footings Mortar Unstable soil conditions (bearing capacity is inadequate) mix of Load transferred from foundations into unsuitable soil, down cement, to bed rock, stiff clay located sand, water Basements – foundation must resist seismic and hydraulic forces Tanking – black compound usd as water proofing ENVS 10003: Constructing Environments

A01 – Logbook

Week: 3

Page: 8


SUBJECT GLOSSARY

 

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Example of membrane system, cables under tension and tied to posts as fixture. Structure is also purely aesthetical Cables do not have structural purpose as stairs are fixed and supported by brick wall Protruding beam and cables give appearance of ‘upholding’ stairs.

Weephole can be seen to be even with floor level Allows effective water drainage in brick cavity wall.

Heritage preservation observed at Oval Pavilion Building influenced by surroundings, hence reconstructed pavilion needs to keep heritage section into consideration.

ßEvidence of efflorescence (salts and lime from soil drawn through brick when in contact with ground. Name:

Lai Yoong Yen

Student ID: 676916

Example of precast concrete (evidence of from form work Wood pattern imprinted onto concrete (wood former leaves impression of surface).

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ß Unlike the bollard, structure is purely aesthetical and does not have structural purpose. Exterior appears to be supporting some sort of mass (judging from bracing and triangulation) but is not. ß Bollard is more than just an addition to overall façade. Acts as structural member, undergoing compression from 3 points. Thick body enables strength.

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Example of cantilever as seen at ABP building under construction During construction, end of cantilever (furthest from main building) is held up by props then removed.

Tiles are saw cut on the surface and allowed to crack through material to create straight lines.

ßUniversal beam used to support overhanging section of deck. Underside reveals use of timber members as joist. Span can be seen between each structural member.

ENVS 10003: Constructing Environments

Examples of blotching on insitu concrete

In situ concrete identified by blotching on surface. Precast concrete identified by smooth surface (concrete poured into mold). Lecture theatre beneath – use of precast structure to avoid usage of columns in lecture theatre. A01 – Logbook

Pad footing Spread point load over larger area of ground Retaining wall Deep vertical element designed to carry vertical or horizontal load Strip footing Loads from walls/series of columns spread in linear manner Substructure foundations of building to transfer all loads acting on superstructure to ground

In situ

Precast

Moments F x d (along line of action that does not pass through point) Applied forces (F) and reaction forces (R) acting on a system

Week: 3

Lintels top part of ball pier wall found in basements Settlement compression of earth beneath, causing building to sink into earth Bearing capacity amount of pressure and load soil can sustain to uphold structure

Page: 9


THEATRE SESSION 04 – CASE STUDY #2 : MELBOURNE UNIVERSITY OVAL

CONSTRUCTION SYSTEMS

TOPIC: FLOOR SYSTEMS AND HORIZONTAL ELEMENTS

Floor systems (Ching, ‘Building Construction Illustrated, p4.03, p4.21)

STRUCTURAL C ONCEPTS Beams Typically horizontal Carrying load along length (secondary) transfer to vertical supports (primary) Support at both ends or various points

One way space

Two way span

Cantilever Cantilever – carry loads along length of member Horizontal, vertical, angled Transfer to supports Supports from one end Point away from support at ends A Open web trusses, and B (overhanging) light weight, closely spaced A Beam Girder

Supports

Heavier joists spaced further apart. Floor must be stronger if spanning further

B Cantilever

Joists further apart, larger span

Span Distance between 2 structural supports Spacing Repeating distance between alike elements Supporting elements (centre to centre) Span + Spacing Spacing supports elements, depending on their spanning capabilities Name:

Lai Yoong Yen

Student ID: 676916

Joist

ENVS 10003: Constructing Environments

Bearer

A01 – Logbook

Concrete - Grid of columns with concrete beam - Slabs of varying types - One or two way spans between structural members - Slab thickness: span of slab/30 - Span type chosen depending on: floor load anticipation, cost, efficiency, function

Steel - UC, RHS, CHS - Grid of steel columns support girders - Heavy gauge structural steel, light gauge steel framing. Used in industrial buildings. - Folded steel sheeting. Stiff one-way, not other. Stiffening spans shorter distance. Efficient material usage - Dead and live load applied from slab to beam. Beam to columns, transfer loads into foundation - Open web joists (web of steel) top to bottom chord. Efficient material use, good for services. Water pipes carried through open webs - Sacrificial formwork (concrete laid on top of decking). Becomes formwork for slab above - Metal form work left permanently in place - Decking provides tensile strength for concrete span.

Timber - Floor boards span from joist to joist - Grid posts/poles connected by beams - Joists support flooring, supported by bearers. 450-600mm floor boards - Mid way bearer so span of joist halved - Combination of bearers (primary) and joists (secondary) - Span of beam determines spacing of piers/stumps, spacing of bearers = span of joists - Bracing of members to stabilise

Week: 4

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