Constructing Environment Logbook Week 1+2
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Transcript of Constructing Environment Logbook Week 1+2
According to the image, the only ratio that we could roughly measure is the ratio of length to width, which is around 3:2. In order to draw the block in an accurate scale, I need to measure the blocks in real life. Then change the length of each side under the same ratio. This task was like working with masonry, which required complement and support from each brick
(wood block in this case).
Order B made the contact area between each block bigger but we did t have enough wood to make the tower high enough. So we only created a base with order B.
Base view from above
The base was built in Older B so that it has more contact area with the ground and the blocks on top.
We decided to put these blocks in this
order A.
Load path diagram
Order B made the contact area between
each block bigger but we did t have
enough wood to make the tower high
enough. So we only created a base with
order B.
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Tension and Compression Rubber band was under a plastic
behavior, so it always wanted to go back to its original form and this will produce forces acting towards blocks. This is the compression force that pushes on the beam. Compression force is now between each brick. Later on when we start to put blocks on top, beams are now under tension.
Or if we put blocks this way and put a rubber band around it. This would also form the opposite of compression: tension.
Another group formed a tower with Order C. However, under the same static
load, order c has more pressure with a smaller contact area than Order A.
load path diagram
The load path at the beginning was very uniform.
As we look at the ground, blocks exerting
forces onto the ground and the ground
push back with force with same
magnitude but in opposite direction.
Reaction force occurs.
As we were trying to close the tower, we
built a triangle base with two beams (four
blocks each) that we made with two
rubber bands.
Load Path
After closing the tower, we tried to take
off as many blocks as possible, the tower
collapsed. I did t manage to take the last
picture before it fell. However, the other
group that did the tower with another
block arrangement also tried to take
blocks off.
We used the same rubber band beam
technic to form a door (gate) for the
tower.
As the sketch shows, the load path go
through the supporting two columns.
The load will always try to find the
closest way to the ground. After the
first block was taken away, the load
path as t uniform anymore but it still
managed to find its new path down to
the ground.
The load path then scape the original
block, which has already been removed.
When there is too much load going
through one point, the structure will
fall down due to too much load. This is
also called point load.
Last second before it fell
Trying to put loads onto another g oup s
tower base. This g oup s tower is a great
represent on how load is transferred onto
the ground.
Just like paper, if we enhance the base and
let the load easily transfer onto the ground
through the strong beam, it might be able
to pass the load into the ground easily.
Load may not be point load like this case
on the right. It just o t be too
concentrating on one point.
Material For a tower with MDF blocks only,
even a very small dynamic load could
ruin the whole structure.
However, this material has it s own
advantages in practice as well, such as
the large amount of production in
Australia, which offers an inexpensive
price of MDF.
Knowledge Map
material
strength
strong
weak
stiffness
Stiff
Flexible
Stretchy
floppy
shape
linear: mono-dimensional
planar: bi-dimensional
volumetric: tri-dimensional
material behaviour
isotropic
anisotropic
economy
sustainability
Tension stretch elongation
Compression push shorten
Load Path-Point Load
Path
Force
Vector:
Magnitude
Direction
+
sense
Scale
This is a kind of soft material and also
very brittle, which means it breaks
immediately after its elastic point. This
property of balsa wood made the
tower construction very difficult.
Because balsa wood are not able to
take heavy loads, especially when we
cut them into stripes.
However, using balsa wood in
construction could be quite sustainable,
because of the recyclability and
accessibility in this country.
Sketching out our ideas brought out
this question about what type of joint
shall we use. We used a triangle base
at first, they looked like that they are
formed with three pin joints, however
since we glued them in order to have a
high stability. They become fixed joint,
because they a t rotate anymore. (No
moment)
This triangle base started up with three
columns.
Fixed joints on the ground are stable to
start with, since it does t allow any
movement in horizontal or vertical
direction. Apart from vertical and
horizontal reactions, it also provides
another restraint, which is called fixed
end moment (associated with the
support from the fixed end).
SH
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Structural System
Framing a tower like this is just like
building a structural system without
the substructure (underlying structure
forming the foundation of the
building). Stability without a
foundation became one of the biggest
problems.
As the tower got higher, we kept
adding fixed joint triangle bases to
brace the three columns and we kept
on bracing for each level.
In the lecture, we used pins to make
pin joints with straws. However,
framing tower with balsa wood, when
it has open grain and very brittle. Once
pins go through them, balsa wood
stripes could easily form a crack and
break.
If we put an extra load, we could easily
make the balsa wood tower collapse.
Because apart of the load will pass
through the balsa wood in the middle.
As a vector, this extra load will add up
with other load in that straight
direction to form the collinear force.
Since the balsa wood stripe is not so
strong, it could easily break even with a
small magnitude force.
Load Path
Load path was very
uniform at the
beginning.
Up to this point, the
load path has already
shifted slightly.
Another group built a tower like this.
This shape provides more possible paths
for loads.
However, the top does t look like a part
of the tower structure system but a
straight antenna. The clever lightweight
top does no harm to the supporting
base.
Comparing with our project, this
tower has a bigger base and more
possible paths for the load to transfer.
This increases the stability of the
tower. Although this tower goes up
really high, once we put some load on
top of it, point load will easily destroy
the tower bracing.
Thinking
We started with the smallest base in
comparison to other g oup s tower.
This did t give us a perfect beginning.
A bigger base could provide a lot more
space for extra balsa wood strips that
could share the load to go into.
Maybe something like this could work
better as a base. The model I made to
represent my brief idea is also shown.
Knowledge Map
Construction System
Requirement
Aesthetic quality
Regulatory quality
Economic quality
Environmental impact
Construction practice
Environmentally Sustainable
Design
Local material
Material efficiency
Thermal mass
Night ait purging
Solar energy
Wind energy
Cross ventilation
Smart sun design
Insulation
Water harvesting
Glossary
Load path: the direction in which each consecutive load will pass throough conntected
members.
Reaction fo e: e e y fo e o o e o je t is a o pa ied y a ea tio . E ual magnitude but opposite direction.
Masonry: is the building of structures from individual units laid in and bound together
by mortar; the term masonry can also refer to the units themselves
Point Load : s a load which is localized to a specific location on a structure
Tension: is the pulling force exerted by a string, cable, chain, or similar solid object on
another object.
Compression: is the pushi g fo e ……….
Beam: is a structural element that is capable of withstanding load primarily by resisting
bending.
Framing: in construction is the fitting together of pieces to give a structure support and
shape a d so eti es is used as a ou su h as "the f a i g" o "f a i g e e s”.
Bracing: a reinforcement used in architecture, such as in timber framing---is a general
term for building with heavy timbers rather than "dimension lumber"
Column: is a structural element that transmits, through compression, the weight of the
structure above to other structural elements below. In other words, a column is a
compression member.