1) The document describes the design process for building a popsicle stick tower that can hold the maximum weight. It details two initial designs that failed, improvements made in the final design, and testing results. 2) The final design used a zigzag bracing pattern, additional horizontal bracing at the bottom, flat vertical joints, and reinforced connections. This allowed it to hold 176.25kg before failure. 3) Testing showed failure occurred when vertical components bent at connection points. Reinforcing these connections with more thread could improve strength further. The efficient final design demonstrated how load is transferred through a skeletal structure.

1. INDEX
Exploration
-Design 1
-Design 2
1
2
Mock up model
-Structural Analysis
-Failure Analysis
3
4
Final Model
- Construction Process
- Structural Analysis
- Model Testing 1 -Timelapse
-Model Testing 2- Timelapse
-Success & Failure Analysis
5
6
7
8-9
10
Conclusion 11
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2. Exploration –DESIGN 1
100mm away from the tip of the popsicle stick, a
2mm x 50mm slit is cut to enable interlocking of
popsicles sticks to form a interlocked square as
horizontal component of the tower.
Using the same method above, the slit is cut in the
middle of the popsicle sticks.
Cross bracing is created in order to transfer force
diagonally.
Cross bracing is slot into the vertical and horizontal
components and will be tied to the connecting point.
Advantages
•Cross bracing helps to spread the load evenly to the both sides.
•A total number of eight vertical components help to strengthen the load
carry capacity of the structure.
Disadvantages
•High shearing force between the components as the cross bracings are
not tie together with the vertical and horizontal
components.
•Middle part of the horizontal component breaks easily when a load
applies to it as it only supported by the vertical component.
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3. Exploration - DESIGN 2
• A slit is cut on diagonal structure to connect to the vertical
and horizontal component.
• String is then used to tie all three components together to
overcome shear stress.
• Vertical and horizontal component are connected
with toothpick and string to create one surface.
• A slit is cut 5mm away from the hole on the horizontal
component.
• Two surfaces are connected by interlocking the
horizontal components.
Advantages
•Toothpick acts as a support to the whole structure.
•High friction between the components and the toothpick gives a
small shearing force to the components.
•A total number of eight vertical components help to strengthen the
load carry capacity of the structure.
Disadvantages
•Horizontal component cracks easily when the slit is cut too near to
the hole which as a result weakens the load carry capacity of it.
•The popsicle stick cracks easily when a force applies to the pin is
press directly into it.
•A big slit is cut in the narrow area of the diagonal component which
as a result causing it to crack.
2

4. From design 1 and 2, a problem that we found
was the joining part of the vertical component as
we have no idea how to connect the upper part
of the vertical component to the lower part.
Before that, we planned to join the upper part of
vertical component by overlapping it end to end
to the lower part of vertical component. However,
we found that force is not transmit vertically from
part to the other part. So, we couldn’t use the
overlapping method in these designs.
Force can’t transmit vertically to
the lower part of the vertical
component
Force transmit vertically to the
lower part of the vertical
component
In order to make the force transmits
vertically downward, we decided to join
them by connecting them end to end to
each other. In order to make them more
stable, we cut out the rounded part of
the vertical components and crafted a
inverted ‘V’. To increase their strength,
we doubled them by joining them with
toothpick.
For the horizontal components, we cut a
slit from 1cm away in the end of them and
then joined them by interlocking them to
each other to create a surface. After that,
we connect it to the vertical component
with toothpick and string like the method
of Design 1.
For the bracing, initially, we planned
to use cross bracing. However, we
found that we had overused the
popsicle stick as we only allow to use
maximum 100 sticks. So, we decided
to diagonal bracing only.
The reasons that we added bracing
was to avoid the whole structure from
shearing and also it helps to transfer
force diagonally to the next component.
Besides, we also added bracing at the
bottom of the structure to reduce force
of the vertical component and to make
the whole structure stable.
MOCK UP MODEL’s STRUCTURAL ANALYSIS
3

5. Inappropriate installation of the bracings
When the uneven force exerted on the tower,
compression occurred at one side of the bracings,
however bracings of opposite side will experience
tension. Due to the uneven spreading of load, the
tower will tend to fall on the side where compression
occurred.
Uneven Contact point with the load and floor
Due to the uneven length of vertical members, not
every members contact to the floor and the load
above. This will directly affect the stability of the
tower which is also the main cause for the falling of
tower when carrying load
Incompatible vertical members
The connection of the vertical members are not
consistent due to the lack of accuracy. The inverted
“V” of the vertical members were not crafted
accurately.T he contact points of the vertical
members had gaps after the tying stage. Due to the
lack of efficiency, the vertical members are crooked.
Slot to slot horizontal bracings
The cut slots weaken the load carrying capacity of
the popsicle sticks.This is due to the narrow surface
area of the lock and key joints. This had result in an
uneven surface of the square.
Unattached joints
Load cannot transfer straight down through the
unattached “V” joints. In contrast, toothpicks
withstand the load
FAILURE ANALYSIS OF MOCK UP MODEL
4

6. FINAL MODEL‘s CONSTRUCTION PROCESS
5

7. Zig Zag Pattern of Bracing Installation
Due to the uneven load distribution of the single diagonal bracing arrange in
parallel way, we change the arrangement of bracing to zigzag pattern. This is
because if one side of the tower experience greater force than the other side
,the compressive force will be offsetting by the tensile force exerting on the
opposite bracing. This will increase the strength of the tower. Other than that
,compressive force will not only concentrate on one side if uneven force
exerted
Horizontal Bracing at the Bottom
Instead of allowing only four contacting point to the floor, we improved
our design by adding one more horizontal bracing to the bottom of tower
,to increase the surface area contacting to the floor. This will further
enhance the stability of the tower and compensate the minor unequal
length of vertical members due to human error.
Changing V joints to flat joints
Due to the technical difficulty, we replaced V join by using flat join , The
straight cut surface allowed full contact with the adjoining members. When
load was applied, load can transfer straight down through the well joined
vertical members .
Using Vertical Core as Formwork
The eight vertical members are temporary attach to a vertical wooden block which
function as a guideline which result having a straight structure. BY using this
mechanism , less error will be occurred as different parts were able to collaborate
well during assembly process .As a result, the structure was firm even before the
tying process. This vertical block was also increase the accuracy and efficiency for
the construction of tower
Increased layers of thread on the joins
Bracings, vertical and horizontal members are tied as one so they are
not likely to slide or shear off. It will hold and fix the members to
prevent movement of members in pressure.
STRUCTURE ANALYSIS OF FINAL MODEL
6

8. Four 10kg load was put on the
model
Six 5kg load was added on
Total : 40 + 30 = 70kg
Six 2.5kg load was added on
Total :70+ 15 = 85 kg
Ten 1.25kg load was added on
Total: 85+12.5= 97.5kg
Four 5kg and four 2.5kg was added on
Total : 97.5 +30 = 127.5
One 10kg load was added was added
Total = 127.5 + 10 = 137.5
Model Testing 1 -Timelapse
7

9. Model testing 2 time-lapse
20kg was put on the
model.
20kg was added on
to the model.
Total: 40kg
(15+15+15kg)=
45kg was added on
to the model.
Total: 85kg (10+10+10kg)=
30kg was added on
to the model.
Total: 115kg
10kg was added on
to the model.
Total: 125kg
8

10. (2.5+2.5+2.5kg)=
7.5kg was added on
to the model.
Total: 162.5kg
(15+10+10+10kg)=
30kg was added on
to the model.
Total: 155kg
(2.5+2.5+2.5+1.25+
1.25kg+)= 10kg was
added on to the
model.
Total: 172.5kg
(1.25+1.25+1.25kg)
= 3.75kg was added
on to the model.
Total: 176.25kg
The upper part of
the model was
bended toward the
right.
The model
collapsed at the load
of 176.25kg.
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11. ANALYSIS OF FINAL MODEL (AFTER TESTING)
After the testing, we have noticed that the breaking points
are at the connections of the vertical component. This is
because when the vertical component is under compression,
the vertical component tend to bend. When the vertical
components are bent, it becomes weaker as only one stick is
holding the weight of the load.
This problem can be overcome by reinforcing the
connections with more thread.
Before After
Efficiency = Load Held (Kg) / Mass of Tower (Grams) x Height of Tower (cm)
= 176.25kg / 108g x 30cm
= 48.96Success
The efficiency of our model is relatively high. This is due to the success of our design and
our design process. At the breaking point of our model, it can be seen that the load fell quite
vertically compared to our mock up model. This is due to the more even base of the final
model and also the stacking of the loads. In our final testing, we have ensured that the
weights are put in such a way that load is distributed evenly to the ground.
The double layer vertical component had made the model successful. We have estimated
that the load will be transferred vertically downward, hence, we reinforced the vertical
components by putting double layer. The horizontal and diagonal components have
successfully held and braced the vertical component to avoid shearing and compression.
Failure
compression
compression
compression
compression
Strength of popsicle
sticks do not
weaken when bent
Strength decreased
as only one popsicle
stick is holding the
load transmitted
through it.
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12. Conclusion
From project 1, we have a better understanding of skeletal structure, its relevant structural
components, understand how a skeletal structure reacts under loading, understanding of how
it works and even be able to manipulate it to solve an oblique design problem. Therefore, we
can apply the technique into construction system design by considering the issues of
strength, stiffness and stability of structures including modes of structural systems, forces,
stress and strain and laws of static.
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