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A01
LOGBOOK
CONSTRUCTING ENVIRONMENTS (ENVS10003)
ANTIGONE GOUGOUSSIS (641138)
2
WEEK 1
E-LEARNING AND READINGS
The e-learning and Ching readings this week introduced the concepts of loads and load
paths (including static, dynamic, wind and earthquake loads), basic structural forces and
materiality. Diagram 1.1 (below) shows the interrelatedness of loads, forces and materiality.
LOADS
Structural Systems of buildings need to support 2 types of loads:
1. Static – applied slowly to a structure without fluctuating rapidly in magnitude or
position, where structure responds slowly to deformation
2. Dynamic – applied suddenly to a structure, usually with rapid changes in magnitude
and developing inertial forces in relation to mass
Diagram 1.1 Loads, Forces and Materiality
3
Load Paths applied loads take the
most direct route in order to reach
the ground, where the reaction
force is equal in magnitude and
opposite in direction in order for a
structure to remain stable.
INTRODUCTION TO MATERIALITY
When deciding which material to use in construction, things to consider include strength,
stiffness, material behaviours, shape, economy/budget and sustainability.
STEEL – Strong in both tension and compression, but more expensive than timber.
WOOD – Much weaker in tension and compression than steel, but more readily
available in Australia.
BRICK/CONCRETE – Very strong under compression, but weak under tension (needs
steel reinforcement if it going to be used in construction and put under tension
forces).
(Left to right) Steel, concrete and timber
Diagram 1.2 Load Path Diagram
4
TENSION AND COMPRESSION
Tension
– forces that stretch/elongate a
material (when an external
load pulls on a structural
member)
– depends on stiffness of
material, C.S.A. (cross sectional
area) and magnitude of the
load
Compression
– forces that push/compress a
material
– opposes tension force
STUDIO SESSION ACTIVITY REPORT: ‘COMPRESSION’
TASK: In the first studio session, we were places into groups and asked to construct a tower
from wooden building blocks in order to help us understand the behaviour of mass
construction and the ways in which loads are transferred through the structural members in
compression structures.
PROCESS AND DISCUSSION:
1. My group decided on our first layout
of placing the blocks vertically as
columns to help achieve height with
our tower. Soon we discovered that
this structure was extremely
unstable as the loads of the applied
blocks were being unevenly
distributed through the structural
members.
Diagram 1.3 Compression and Tension
5
2. Structural members placed in different ways
as tower construction was rushed while
attempting to curve the walls of the
structure. This led to loads being unevenly
distributed through the structure and
instability of the tower. Therefore, we
changed our design concept.
3. New attempt was made with curved walls and new design layout of blocks in order
to distribute the applied load of the blocks as equally as possible through the
structural members.
Diagram 1.4 Initial Tower Structure
6
4. Our final tower design allowed for all loads to be distributed equally through
structural members. Although our final tower attempt wasn’t as high as we had
hoped for, we managed to create a tower able to withstand compressive forces
created by applied loads. We tested the strength and sturdiness of our tower by
placing heavy objects on top of its roof, which it was easily able to carry.
Diagram 1.5 Final Tower Structure
7
5. By applying loads on top of the structure, this
allowed for structural members to be under compression
and tension forces. The roof of our structure was hurried
and did not follow the base and main body of our tower’s
structure.
6. However, the layout of our tower allowed for the
loads causing these forces to be transferred equally
throughout the structural members, therefore reducing
the magnitude of the compressive forces on each block.
This allowed for a strong and sturdy final structure.
Diagram 1.6 Forces on each block for Final Tower
8
WEEK 2
E-LEARNINGS AND READINGS
This week, the e-learning modules and Ching readings introduced the concepts of structural
form and structural joints. The concepts mentioned throughout the e-learning classroom
included the different types of structural systems, the 3 main structural joints used in
construction and building, and construction strategies (including ESD strategies and
selecting materials).
Figure 2.1 Structural Forms and Joints
9
CONSIDERATIONS WHEN CONSTRUCTING SYSTEMS:
PERFORMANCE
Need to be easily maintained
building needs to resist wear
and tear
AESTHETICS
Polished finishes, aesthetic
materials
e.g. surfaces for hospitals
ECONOMICS
Affordability
Cost of materials, labour, etc.
life cycling costing
ENVIRONMENT
Embodied energy in materials
artificial lighting or natural
lighting
Figure 2.2 Construction Systems
10
ESD (ENVIRONMENTALLY SUSTAINABLE DESIGN)
STUDIO SESSION ACTIVITY REPORT: ‘FRAME’
TASK: In this week’s studio, we were placed into groups and required to cut up a piece of
balsa wood into thin strips in order to create a structure as tall as possible.
PROCESS AND DISCUSSION:
1. The balsa wood was cut into thin
pieces. We decided we wanted the
pieces to be as thin as possible so we
could get as many strips as we could to
build our tower to a maximum height.
At the same time, we wanted the strips
to be strong enough during the
construction process so these
structural frame members would not
break under the tension forces.
Figure 2.3 Common ESD Strategies
11
2. We made the base an
equilateral triangle for support
and stability while building
upwards.
3. The balsa wood strips were
found to be very thin and
began to bend and break easily
when put under small amounts
of stress.
4. As we built our tower further,
it began to lean to one side as
a result of uneven lengths of
the structural members. This
began to cause problems in stabilising our tower and put certain members under
greater stress than other, meaning certain sticks were carrying greater loads. This
made certain parts of our frame structure more fragile than others.
Figure 2.4 Tower top
12
5. We decided to add more triangulated
frames in our structure as we built
upwards, so that the vertical structural
members were less prone to snapping
under tension forces. All the joints of our
structure were fixed joints, and this
caused much stress in the supporting
structural members as it prevented all
horizontal, vertical and rotational
movements.
6. The top of our structure consisted of a
pyramid frame structure, in order for all
loads to be transferred and equally
distributed down members of our towers’
structure.
7. Our final tower was very
fragile and easy to fall over. I
think the frame structure
could have been stabilised
more by building a much
larger base, whilst allowing
the tower to become smaller
in its cross sectional area as
we built upwards. Due to the
lightness of the balsa wood
material, the structure was
easily pushed over.
Figure 2.5 Final Tower Frame Structure
13
8. The structure could have been made more
stable by using slightly thicker strips of
balsa wood and by measuring our
structural member more carefully to create
a more symmetrical, stable structure.
Figure 2.6 Possibly Improved design
14
GLOSSARY
Anisotropic: different physical properties in different directions (e.g. wood – stronger along the grain)
Beam: rigid structural members, carry and transfer transverse loads across to supporting elements
Bracing: supports to a structure
Column: a pillar standing upright, subject to compression
Compression: forces that push/compress a material
Couple: a force system of two equal, parallel forces acting in opposite directions and tending to produce rotation but
not translation
Dynamic loads: loads applied suddenly to a structure with rapid changes in magnitude e.g. earthquake and wind loads
Earthquake loads: longitudinal and transverse vibrations induced in the earth’s crust resulting from the movement of
plates along fault lines (weak spots)
Frame: rigid structural members joined at the corners
Impact loads: kinetic loads of short duration e.g. from moving vehicles and machinery (static load)
Isotropic: Same physical properties in different directions
Lateral load: the force acting on a structural member in the horizontal direction, the forces working against a structure
e.g. wind pressure against a building
Live loads: moving or moveable loads on a structure e.g. collected snow, water or moving equipment
Load: the overall force which a structure is subjected to, including mass or weight, externally applied forces (snow, rain,
equipment, etc.)
Load path: the path in which a load (applied) will pass through structural members of a structure in order to reach the
ground
Masonry: building structures using brickwork and stonework
Moment: the tendency of a force to produce rotation of a body about a point (clockwise or anti-clockwise direction)
Point load: a load applied on a certain point of a beam (load concentrated on a small area of a structural member)
Reaction force: forces that are equal and opposite in reaction to the applied forces in order for the structure to remain
stable
Settlement loads: loads resulting from the subsidence of soil and causing movements in the foundations
Stability: being stable, resistant to falling over
Static load: loads applied slowly to a structure until it reaches peak value, allowing the structure to respond slowly to
deformation
Structural Joint: join structural members at a point
Tension: forces that stretch/elongate a material (pulls on structural member)
Wind loads: the forces exerted by kinetic energy of a moving mass of air (assumed to come from any horizontal
direction)
15
References:
Ching, F 2008, Building Construction Illustrated, 4th edn, John Wiley & Sons, Hoboken, New Jersey.
Gregory La Vardera Architect 2006, Steel Beam, image,
<http://blog.lamidesign.com/2006/03/6030-house-floor-beam-day.html>.
Kandla Timber Directory 2014, Timber Beams, image, < http://kandlatimberdirectory.com/>.
Newton, C 2014, W01 m1 Introduction to Materials, YouTube,
<http://www.youtube.com/watch?v=s4CJ8o_lJbg&feature=youtu.be>.
Newton, C 2014, W01 s1 Load Path Diagrams, YouTube,
<http://www.youtube.com/watch?v=y__V15j3IX4&feature=youtu.be>.
Newton, C 2014, ESD and Selecting Materials, YouTube,
<http://www.youtube.com/watch?v=luxirHHxjIY&feature=youtu.be>.
Newton, C 2014, W02 c1 Construction Systems, YouTube,
<http://www.youtube.com/watch?v=8zTarEeGXOo&feature=youtu.be>.
Newton, C 2014, W02 s1 Structural Systems, YouTube, <http://www.youtube.com/watch?v=l--
JtPpI8uw&feature=youtu.be>.
Newton, C 2014, W02 s2 Structural Joints, YouTube,
<http://www.youtube.com/watch?v=kxRdY0jSoJo&feature=youtu.be.>
Selenitsch, A 2014, Framework for Analysing Form, YouTube,
<http://www.youtube.com/watch?v=KJ97Whk1kGU&feature=youtu.be>.
Online Architecture and Design Exhibition 2014, Concrete Beam, image, <
http://www.archiexpo.com/prod/prestasi-concrete-sdn-bhd/prestressed-concrete-i-beams-56829-
126838.html>.
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