Phase Changing Material Behaviour
Deposition Method Studies | 1
“negotiating structural system using sodium acetate
Studio Shajay Bhooshan Span Andreas Y. Kyriakou (Cyprus) Ashwin Balaji A (India) Jitesh Jadhav (India)
STUDIO SHAJAY BHOOSHAN WORKSHOP I
Architectural Association School of Architecture AADRL Design Research Lab
London November 2014
Δspan TEAM MEMBERS Andreas Y. Kyriakou
Ashwin Balaji Anandkumar Jitesh Jadhav
TUTORS
Shajay Bhooshan
Pierandrea Angius Tyson Hosmer
BRIEF
Light, strong, long, spanning bridge using deposition materials
Contents DEPOSITION METHOD STUDIES Candle Wax Deposition Sodium Acetate Preparation Sodium Acetate Deposition
9 10 14 20
BRIDGE STUDIES Stick / Sodium Acetate Models
25 26
DIGITAL EXPLORATION STUDIES nParticle Exploration - Catalogue
41 42
Workshop Brief The brief of the workshop was to build the lightest, strongest bridge which can span one meter using sodium acetate. Studying the material behaviour, complexity, constraints and parameters were the factors to be considered. It included in-depth exploration of the various deposition methods used for depositing sodium acetate. Developing the methods, observing the constraints of the material and designing a truss system which could be used to span a meter long bridge.
8 | Deposition Method Studies
Deposition Method Studies | 9
DEPOSITION METHOD STUDIES
CHAPTER 1
10 | Deposition Method Studies
Candle Wax Deposition
CHAPTER 1.1
Candle wax is an interesting approach to study the deposition method, an addition deposition method which results in creation of interesting geometry and spaces .It gives an overall understanding of the deposition process which included parameters like rate of deposition, studying load distribution, junction and joineries. Different dripping technique created different intuitive spaces and geometry. Water was introduced as an element to increase the deposition speed which helps to harden the wax when you start the dripping process. The number of the dripping agents can be controlled by increasing the number of candle used. Rate of deposition can be controlled by controlling the heat factor. Heat gun proves to be a salient tool to control the heat subjected to the junction.
Deposition Method Studies | 11
Initial attempts
Syringe
Lighter
Candles
Tools used for candle wax experimentation method
Potential structure Flipping it horizontal
Addition of wax in the base
Addition of second candle and twisted at the top
Candle melted and raised vertical
12 | Deposition Method Studies
Vertical Wax Deposition
Diagram of the process
Physical artefact wax, intuitively produced
Adding horizontal elements on either sides
Adding vertical support on either sides
Column with broader base
Deposition Method Studies | 13
Vertical + Horizontal Wax Deposition
Diagram of the process
14 | Deposition Method Studies
Sodium Acetate Preparation
CHAPTER 1.2
To make a successful model, the solution is the key. Sodium acetate and water should be in right proportion and should be heated and cooled well. Since the solution is prone to crystallize easily due to factors like dirt in the syringe or in the cup or disproportionate ratio of sodium acetate and water. Its important to seal the cup and sterilize the syringe before starting to use.
Deposition Method Studies | 15
16 | Deposition Method Studies
How to prepare sodium acetate solution 1
heat for 10 mins
2
add water after 10 mins of boiling
100g
25ml
C2H3NaO2
H2O
5
3
transfer the solution to a wrapped container
4
cool in either fridge or room temp for 90 mins
6
Deposition Method Studies | 17
5 mins
10 mins
15 mins
20 mins after adding water
18 | Deposition Method Studies
Sodium acetate - a phase changing material
When studying about the behaviour of the material, the main observation noted was that the material reflects its strength depending upon various parameters like the amount of water added when preparing the solution, the amount of the time is has been cooled and the crystallinity of the material itself. The solution is prepared by adding 25 ml water in 100 gm of sodium acetate ideally. The mixture is heated for some amount of time until it turns into complete liquid and allowed to cool in the fridge for around 90 mins. The solution thus prepared is pumped into a syringe and used for deposition when dropped from a syringe it changes its phase from liquid to solid. Scenario 1 When proper proportion of sodium acetate and proper amount of water is added. The solution thus obtained is quite sturdy, strong and is proper white is colour when deposited. Scenario 2 When the proportion of water is excess while preparing the solution. The deposition content got after deposition is quite limpid in its state and can be felt a little soft when exerted pressure on it. Scenario 3 When the proportion of water is less in the solution then the solution will get crystalline in the container itself when taking into the syringe.
Deposition Method Studies | 19
Scenario 1
Scenario 2
Scenario 3
20 | Deposition Method Studies
Sodium Acetate Deposition
CHAPTER 1.3
Deposition is the integral part of the system. Addition deposition method was used to design the structure and the geometry. The most critical problem observed during the deposition process was crystallization. The sodium acetate solution was being pumped into a syringe which is preheated in warm water so as the solution in the container doesn’t get crystallized. Material deposition was done using syringes of various thickness which included 50ml, 20ml and 10 ml. A needle was attached in the syringe to get more control over the thickness and the deposition method. Minute strands were formed using a needle attached to a smaller syringe so as to get more precision and light weight pieces. Various levels of thickness was used in the deposition process so as to generate proper load distribution in the system. The base having the thickest members and reducing the thickness as moving towards the centre.
Deposition Method Studies | 21
Syringe w/ needle
50ml Syringe
20ml Syringe
Tools used for sodium acetate deposition method
Initial attempts - failed models FAILED
FAILED
22 | Deposition Method Studies
First successful structure (forming a structural truss system)
Deposition Method Studies | 23
Vertical direction structure
Vertical triangulation / diagonal deposition
Horizontal triangulation
Three starting points / base with thick members
24 | Bridge Studies
Bridge Studies | 25
BRIDGE STUDIES
CHAPTER 2
26 | Bridge Studies
Stick / Sodium Acetate Models
CHAPTER 2.1
Stick model was used as a diagrammatic method for studying the structural frames. Different binding agents were used in the process like clay, glue and sodium acetate. The stick model study was vital before proceeding to use sodium acetate material. It was helpful in conceiving the geometry and the process was mostly intuitive by adding the sticks when and where needed. Sodium acetate was the protagonist of the entire workshop. Initial attempts of sodium acetate models gave more understanding of the material behaviour than constructing a particular geometry / form. Since the initial attempts were vertical in nature, the next stage was to develop few strategies to build it horizontally. Finally the idea of bridging was achieved by tilting the column at a certain angle and extruding the face of it. Sodium acetate model exploration was helpful for final design as few components like base were taken from the initial attempts.
Bridge Studies | 27
Design approach
Conventional Spanning bridge
Bottom to top approach
Bridging the two structures
28 | Bridge Studies
Stick Models as Diagram / Replication / Deposition
Stick models plan
Evolution of form
Replication of stick models to sodium acetate
Bridge Studies | 29
Attempt to bridge the column structure
Linear bridge spanning
30 | Bridge Studies
Sodium Acetate Module Repetition
Plan of the model
Module
Elevation of the model
Form evolution
Bridge Studies | 31
Bridge Experimentation 45o - inclination
Base similar to the previous model experimentation
Model
PMM=達達
QR
OQM=達達
Lateral supporting frame
tesselation pattern
spine
Broad base
Diagrams of the construction process
32 | Bridge Studies
Bridge Experimentation 60o - inclination
Base similar to the previous model experimentation
Model
PRM=達達
SM=
Spine
Broad base
Tessalation pattern
NRM=達達
Diagrams of the construction process
Bridge Studies | 33
Cantilever Experiment
Hexagonal Base Cantilever bridge experiment was done with a hexagonal base with six major supporting framework where the load is equally distributed from top to bottom.
Diagram of the structure
Triangulation Method
34 | Bridge Studies
Deposition / Construction process
Bridge Studies | 35
Extent of Cantilever - Comparison Study
450 mm
550 mm
350 mm
Angle
500 mm
380 mm
65
65o
0
FAILED
320 mm
70
70o
0
FAILED
75o 75
0
SUCCEEDED
36 | Bridge Studies
0.90 meter Bridge
400mm
Failed Attempt
400mm
The left part of the bridge failed because of the wrong inclination.
Bridge Studies | 37
Evolution Process of right-side Structure
38 | Bridge Studies
Final Structure - 0.9 m Bridge
Bridge Studies | 39
40 | Bridge Studies
700 mm
900 mm
41 Bridge | Bridge Studies Studies | 41
0.9 meter span structure using cross-bracing Various method of material deposition were being implemented. It was observed that when material is deposited in a vertical stream it has a tendency to twist after certain height and has a tendency to break. It works best when the material is being deposited in certain angles. The angle of inclination, thickness of the member’s and the rules considered for constructing the geometry were some of the predominant factors considered. Different level of thickness were used for different areas of the geometry. The thickness kept on reducing as it moved to the center of the geometry with a understanding of base being the thickest and strongest, while reducing the load on the structure by reducing the thickness of the member as you move towards the center of it. The main components of the geometry were the base,spine,cross bracing and mesh pattern which was supported by cross bracing. The base had the thickest member’s so as to take the load which is subjected to it.It had six touch points on the ground to support the configuration above. Deposition was done at certain angles so as to form stronger nodes which could take the weight of the profile. Diagonal members were provided to support the profile of the base. The spine was the main membrane which held the whole configuration together. The surface pattern created were connected to the spine transferring the load to the base. A tessellation pattern was formatted creating nodes junction at various levels. Various angle of inclination were used for the mesh pattern developed. Tests were performed to derive the angle of inclination to create the profile above. The angle of inclination was showed superior result was 70 degree inclination. Cross bracing supported the spine and the tessellation pattern formed it transferred the load to the base. The idea of bracing back into the structure as you go higher was an interesting idea derived.
0.5 mm dia 1 mm dia
0.5 mm dia
70
cross bracing
0
angle
0
nozzle type
42 | Digital Exploration Studies
Digital Exploration Studies | 43
DIGITAL EXPLORATION STUDIES
CHAPTER 3
44 | Digital Exploration Studies
nParticle Exploration - Catalogue
CHAPTER 3.1
nParticle exploration (via Autodesk Maya) was done to explore on the different possible deposition methods digitally. By creating emitters of different numbers, sizes, angles and paths, deposition method was simulated. The catalogue comprises of series of the same family by setting up emitters with the use of gravity and paths without gravity.
Digital Exploration Studies | 45 # emitters: 1
# emitters: 2
# emitters: 2
# emitters: 3, 4, 2 same path
46 | Digital Exploration Studies # emitters: 3, 4, 5
# emitters: 1, 2, 3, 4 sequential increase
# emitters: 4 emitters at different levels at z-axis
# emitters: 4 emitters at different coordinates
Digital Exploration Studies | 47 # emitters: 6
# emitters: 4, 8
emitters follow certain paths high level of complexity
# emitters: 4 emitters at different positions and different paths
48 | Digital Exploration Studies
Architectural Association School of Architecture, London November 2014