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

Knowledge Map

Load Dynamic

Load

Static Load

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).

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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

Knowledge Map

Structural System Structural Connection Construction System

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.

Reference

http://toolboxes.flexiblelearning.net.au/demosites/series10/10_01/content/bcgbc4010a/

01_loads_loading/01_primary_loads/page_008.htm

http://en.wikipedia.org

Ching

http://www.highaccess.co.uk/glossary-of-terms