Constructing Environments Logbook Brydie Singleton !Week One - Introduction to Construction ! !!!

Load - a weight or source of pressure borne by something or someone Load Path - the path the load takes to reach the foundation !!Load travels down columns - and is then transferred outwards into the beams. It takes the most direct routes to the ground, thus there will be elements of the structure that do not work towards supporting the applied load. !These applied loads then have a reaction with the ground (a fundamental law of structure: the reaction with the ground is equal and opposite to the applied loads) - which makes the structure stable. !!

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Static Loads!assumed to be applied slowly to

a structure until it reaches its peak value without fluctuating rapidly in

magnitude or position. (Ching)

Occupancy Loads!the weight of people, furniture, stored material in a building. !

Snow / Rain Loads!the weight created by the

accumulation of snow/rain on a roof.

Live Loads !moving or movable loads on a

structure. Typically acts vertically downward (but may act horizontally as

well). !Dead Loads!

the self-weight of the structure and building elements permanently

fixed to it. Acts vertically downwards.

Impact Loads !loads of short duration

due to the impact of moving vehicles, equipment and

machinery

Settlements Loads!imposed on a structure by the

supporting soil and the settlement of the foundation !

Ground Pressure!the horizontal force a soil mass applies on

the vertical features of the structure !Water Pressure!

the hydraulic force groundwater applies on the foundation !

Thermal Stresses!the pressure developed in a material

when constrained agains thermal expansion or contraction

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!!!!!!!!!!!!Introduction to Materials !!Five different elements to consider: ! !

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Wind Loads!force applied on a structure

due to kinetic (relating to motion) energy of a moving mass of

wind, from any horizontal direction

Flutter!rapid movements of a flexible membrane

structure caused by the aerodynamic effects of

wind

Earthquake Loads!a series of longitudinal and traverse

vibrations produced by the earth’s crust due to plate movements. Base shear is the design value

for the total lateral seismic force on a structure that acts in a horizontal direction. If this load is applied at

a distance above grade, it can result in the overturning of a structure. To ensure equilibrium,

the overturning moment must be counterbalanced by a restoring moment

(provided by the dead load) Moment!the tendency of a force to produce rotation of a body

Force!any influence that produces a

change in shape or movement of a body. It posses both magnitude and

direction (vector). Represented by an arrow whose length is proportional to magnitude

and whose orientation represents the direction. !

Collinear forces occur along a straight line.

Tension Force !when an external loads pulls on a

structure, it undergoes tension and the particles composing the material move

apart. !This stretches / elongates the material. The

extent to which this occurs depends on the stiffness and area of the material,

and the magnitude of the load.

Compression Force !(the opposite of tension force) !

when an external load pushes on a structure, it undergoes compression and the particles compact together. !

This results in the shortening of a material.

Dynamic Loads!applied suddenly to a structure,

often with rapid changes in magnitude and point of

application. (Ching)

STIFFNESS !- flexible e.g. carpet,

rubber - stiff e.g. steel

SHAPE !- mono-dimensional (linear)

e.g. rope - bi-dimensional (planar) e.g.

sheets of metal -tridimensional (volumetric)

e.g. bricks

MATERIAL BEHAVIOUR !- isotropic - displaying similar

characteristics regardless of which direction the force is

applied in - anisotropic - having different

physical value when measured in different

directions

STRENGTH !- steel is strong in both compression and tension

- brick and concrete is strong in just compression

ECONOMY / SUSTAINABILITY !

- how expensive is it - how available is it

- how far does it have to travel - how efficiently does it get used

- what impact does the manufacturer have on the

environment

Theatre Activity Report : Aim was to create, out of a sheet of paper, a structure that was strong enough to support a brick. !!

This was the structure that was most successful/strong. This may be due to the equal distribution the form of a circle creates, thus all all loads travelling to the ground proportionately. (uniformly distributed load). !!!!!!!!!!

Studio Session Activity Report: Objective was to build a tower as high as possible using compressed fibre blocks, with space for a small plastic toy dog to enter in and out. !!!!!

My group started off by deciding to build the tower on the upside on a table, in order to minimise any imbalance the soft surface of the carpet may have created. We then employed a brickwork format - with each block slightly overlapping the next. This meant that holes could be left in the structure in a regular manner as to not compromise the stability, and as a way of minimising the number of blocks used (efficiency). It was a stable structure, although it was not built as quickly as other groups’, therefore not reaching as great a hight. !!!!!!!

Examples of other groups: !!!!!!Their strategies included: !-becoming thinner as the structure rises (which was difficult to employ with our design due to the parallelism) !-using a circular base as opposed to a square base !!

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Week Two - Building systems!!!

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!!Factors to be considered when selecting, assembling and integrating building systems and construction:!!

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A building!the physical embodiment

of a number of subsystems that must be be related,

coordinated, and integrated with each other, as well as with the three-dimensional form and spatial organisation of the

building as a whole. (Ching) Structural system!

serves the purpose of supporting and transmitting applied

gravity and lateral loads to the ground without exceeding the allowable stresses in

its members. !- superstructure: the vertical extension of a

building about the foundation - substructure: the underlying structure

forming the foundation - columns, beams, and load-bearing

walls support floor and roof structures

Enclosure system!

is the: shell of a building, consisting of the roof, exterior walls,

windows and doors. !- roof & exterior walls shelter interior spaces

from weather, control moisture, heat, and air flow, dampen noise and provide privacy for

the occupants - doors provide physical access

- windows provide access to light, air and views

- interior walls subdivide the interior into spatial units

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Mechanical systems !provide essential services to a building !

- water supply system provides water for human consumption and sanitation

- sewerage disposal system removes waste - heating, ventilating and air-conditioning systems

condition the interior for the comfort of the occupants - electrical system controls, metres and protects the

electrical power supply to a building (power/lighting/security/communication systems)

- vertical transportation systems carry people/goods from one level to another

- fire-fighting systems detect and extinguish fires

Performance requirements!- fire resistance, prevention and safety - control of heat and air flow - control of condensation of water vapour - accommodation of expansion or contraction with changes in

temperature/humidity - noise reduction, sound isolation and acoustic privacy - resistance to wear, corrosion and weathering - finish, cleanliness and maintenance requirements - safety in use !Aesthetic qualities!- relationship of building to its site, adjacent properties and

neighbourhood - form, colour, pattern, texture and detail qualities !Economic Considerations!- initial cost (materials, transportation, equipment, labor) - life-cycle cost (maintenance and operating costs, energy

costs, useful lifetime, demolition and replacement)

Environmental impacts!- conservation of energy and resources of building

design - energy efficient mechanical systems - use of resource- efficiency and non-toxic materials !Construction Practices!- safety requirements - Occupation Health and Safety

Act - industry standards - division of labor and coordination of building trades - budget constraints - time requirements - provisions for unpleasant weather !Regulation constraints (building codes)!!

Different Structural Systems!!! !!!!!!!

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!!!!!!!!!!!Structural Joins !! !!!!!!!!!!!!!

!!!!!!!!!!!!!!Trusses - a structure comprising of triangular units that works essentially like a beam. It is extremely stable and economical as it uses less material. !!!

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SOLID SYSTEMS !- found in early buildings (e.g.

Egypt / great wall of china) working with stone, brick or mud

structures. - Compression is the main

structural action found in these systems (arches are very

efficient).

SHELL SYSTEMS !- thin, curved plate structure

shaped to transmit applied forces

- e.g. Sydney Opera House - plannar structure

FRAME / SKELETAL SYSTEMS !

- possibly the most common system today

- efficient way of transferring loads down to the ground

- e.g. the Eiffel Tower

MEMBRANE SYSTEMS !- used less commonly

- very efficient in tension - e.g. sport stadiums where the

objective is to cover large areas (cheap and efficient

way of doing so)

HYBRID SYSTEMS !- multiple structural system in

conjunction with each other - e.g. a farm system with

cladding

- less common - loads transferred only in

one direction (vertical), until force is exerted in any other direction, then roller moves in the horizontal axis

- very common - allows rotation at the pin

(like a hinge) - modes of action can be

in two directions - used in trusses

- no movement or flexibility between joints

- most complicated joint because bending can occur

- if a load occurs in one member, it can cause a bend at the joint

- used commonly for cantilevered structures

!Environmentally Sustainable Design (ESD)! !!!!!!!!!!!!!!!!!!!!!!!!!!!LIFE CYCLE - begins with the extraction of raw materials from the Earth and ends with the disposal of waste products back to the Earth or recycled. !!

Stages !!1.Raw material acquisition !2.Primary processing and refining !3.Manufacturing !4.Delivery !5.Construction use and maintenance !6.Final disposal !!!!!!!

REDUCE, RE-USE, RECYLE!- can you reduce the items that are used in construction? - are any items designed for re-use? - can materials be recycled? can you use recycled materials? !CARBON FOOTPRINT - a measure of the amount of greenhouse gases generated during the production and transportation of a product. !The embodied energy - the total energy used during all stages of a material’s life. This applies to the construction of buildings. (definition from Materials for sustainable sites, by Meg Calkings (2009), page 30)

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http://www10.aeccafe.com/blogs/arch-showcase/2012/10/25/mojave-rivers-ranger-station-in-acton-california-by-marcy-wong-donn-logan-architects/15-mojave-rivers-ranger-station-sustainable-diagram-section/

!U.S. Environmental Protection Agency, Adapted from "Design Guidelines for Sustainable Packaging,” Sustainable Packaging Coalition, Green Blue, 2006 - http://www.epa.gov/smm/basic.htm

!Environmentally Sustainable Design (ESD) Strategies !!- Local materials!- Material efficiency!- Thermal mass - over night as a building cools down, heat is released, then taking time for the building to heat up

again. Thus in winter can provide heating throughout the day. - Night air purging - keeping windows and passive ventilations openings closed during the day, but open at night to

flush warm air out of the building. - Solar energy - to warm - Wind energy - to drive systems that rely on energy - Cross ventilation - air entering on one side of the building, and leaving on the opposite side - Sun smart design!- Insulation!- Water harvesting - rain water as well as black water (recycling sewerage waste developed within a building) !!!Theatre Activity Report : !Aim was to build a 'water tank' structure using four straws and a plastic container. Different strategies to increase the load capacity were trialled. This included: stronger joint connections using 2 pins per column rather than 1, triangulation of posts, bracing between posts, spreading the load onto a larger footing and shortening the post length. !!!Studio Session Activity Report: !Challenge was to, using only a single piece of bolsa wood, to build a stable tower as tall as possible. !!!

-My group started off by deciding that a structure with a triangular base would be the most stable option. -We then drew a sketch as we conceptualised and designed our structure. -After this, the bolsa wood was cut into thing strips, and attached together in a truss-like structure. -Half way through, the structure seemed slightly flimsy so we decided to add some bracing between posts - by inserting additional diagonal pieces of bolsa wood. -The joints were composed with masking tape. -Our tower did not reach the roof, however it did reach a considerable hight. !

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