Year 05 - Costa Rica Workshop

Veritas x U22 Bartlett Workshop

WORKSHOP TIMELINE Start Date 28 November 2014

28 NOV 29 NOV 3 DEC

Email recieved about “One day competition amongst U22 students“

Student go away to prepare a 3 page spread for a prototype that are related to this term’s design project.

Competition Submission Day

Havana, Cuba

Submission

Selected projects :

Competition Winner announced

London, UK

Sirisan Nivatvongs Nawanwaj Yudhanahas Haiti

Journey to Costa

Santo Domingo, Dominican Republic

Workshop Day 1

8 DEC

Welcoming Ceremony at Veritas University and listening to Unit Agenda Presentation and the 2 competition winner

Present project and competition brief. Unit is split into two groups of 7. Each group is joined by 7 students from Veritas University.

Day of Discussion with teammates then 2 tutorials and drawing up a material list

Organization of ideas and attempting to formulate a prototype, using the joint as a starting point.

Workshop Day 2

9 DEC

Material search and further discussion with team about the overall scope of the design

Allocation of a site. Division of the group into 4 sub-groups looking into different elements of the design.

Group a - Pulley Group b - Clip structure Group c - Hammock Group d - Screens

Each Group goes away for discussion.

Meeting up again later in the afternoon followed by a tutorial

Drawing of Site Model on Sketch up and Clip Componant

Construction of each component starts

Drawing and cutting out the pieces for the Clip Componant in the workshop.

Workshop Day 3

10 DEC

Continuation of the construction of componants

Progressing further the design of the Clip Componant together with the Pulleys and overall support for the prototype.

First assemblage of prototype on site

Removal of steel wire on site and designing further componants to cope with any structural faults the prototype was facing.

Workshop Day 4

11 DEC

Tegucigalpa, Honduras Guatemala, Guatemala San Salvador, El Salvador WHO?

PROGRAM?

A collaboration between students and tutors from Unit 22 of the Bartlett School of Architecture, University College London (UCL) and the Faculty of Architecture of Veritas University, San Jose. Organized by Bartlett turos Carlos Jimenez, Izaskun Chinchilla and teaching partners of Veritas University.

The workshop took place between the 8th December and end on the 12th of December. Comprised of full day construction based design. Using mostly low cost material and based upon the concept from 2 competition projects.

WHEN? Brief and Development during Term 1 and November Competition.

Bartlett Students arrive at Veritas University on the 8th December.

Construction finishes on the 12th December.

WHAT? Two 1:1 Prototypes built around the Veritas University Campus.

WHERE?

Assembling the prototype on site: Assisting different Groups to address structural faultsImplementing the triangulation, securing the foundations, assembling the frame for the screen, creating the design for the counter-weight in-situ.

Continuation of the construction of componants

Each prototype will be decided at a site of the group’s choosing. The site has to be located within the vacinity of the architecture faculty.

Managua, Nicaragua

San Jose, Costa Rica

SIZE? There were no specified size for the construction of the prototype. However the scale of the installation had to be at a 1:1 scale.

MATERIAL

Bogotá, Columbia

Beyond the salvaged material from skips and garbage collection points, there was a limited supply of material from our sponsers. Therefore we were encouraged to make the best use of the materials we can find.

BUDGET There was a budget enough to pay for such materials as rope, tires and bicycle wheels.

SPONSERS The project is sponsered by The Bartlett School of Architecture and Veritas University

Workshop Day 5

12 DEC

Adding final touches to the prototype

Helping Group 2 to assemble their prototype

Final Presentation

Panama, Panama

X The 3 pages that were submitted to the blog during competition stage

STRUCTURAL COMPARISONS Comparable elements between 1:6 Model and 1:1 Installation

ATTACHING STRUCTURE

#A

#A

Both projects utilize the combination of structure + clasp in order to hang or attach an additional elements. In my 1:6 model I have included a clipping joint similar in approach. This includes 2 plates joined together, sandwiched between a single structural beam. In the case of the 1:1 prototype, a U-shaped wooden bracket was used to clamp onto the I-Beam.

BRACING AND TRICANGULATING

#B

#B A triangle does not easily deform and is able to balance the stretching and compressive forces inside its structure. Overall, a triangle is the simplest geometric form that will not change shape when the lengths of the sides are fixed. Triangular elements are ubiquitous in the 1:6 model. And in the 1:1 prototype was key in allowing the structure to achieve overall stability.

STRING UNDER TENSION

#C

#C

In principle when a string recieves tension, the segment of the string pulls on and is pulled upon by its neighboring segments, with a force equal to the tension at that position along the string. In our 1:1 prototype we experiment with the behaviours of strings under tension within a pulley system. In the 1:6 model, string was used to anchor down the structure.

HOLLOW STRUCTURAL SECTION

#D

#D

In the 1:1 prototype, the vertical tube column shows a proneness to buckling. This is a type of instability, that leads to failure mode. It happens when a material is stressed beyond its strength limit, thus causing excessive deformations. The 1:6 model shares a similar circular profile column, which shares similar structural behaviour. However the instability experienced in the 1:6 model was in the form of torsion.

HANGING SCREENS

#E

#E The hanging screens seperates the user from view from within the building, giving he or she privacy. It is made out of reclaimed wooden panels. The concept was taken from the initial iteration of the folding joint. In the 1:6 model screens and curtains were also used as partitions.

ANALYSIS PART #A Attaching to existing infrastructure

1:1 PROTOTYPE

INSTALLATION DRAWINGS

REFLECTING ON STRUCTURAL FINDINGS Clamping (Screen Frame)

y-axis

I-BEAM

h/2 Clamping (Pulley)

Web

h

Flanges

x-axis

centroid h/2

Clamping (Counter weight) b The parallel portions on an I-beam are referred to as the flanges. The portion that connects the flanges is referred to as the web.

Deflection

b/2

Consider a simply supported beam of length, L. The cross section is rectangular, with width, b, and height, h.

b/2

An area has a centroid, which is similar to a center of gravity of a solid body.

The centroid of a symmetric cross section can be easily found by inspection. X and Y axes intersect at the centroid of a symmetric cross section, as shown on the rectangular cross section.

P

L P

Δ

P

(load)

L

(length)

Inertia is a measure of a body’s ability to resist movement, bending, or rotation.

I

(moment of intertia)

Material property that indicates stiffness and rigidity

E

The variables in analysing the Deflection are

Rough plan sketch showing the different elements clamping to the I-beam

Clamping (Pulley)

e

d

f

c

g

b

2 3

1

4

5

6

7

1. Finished installation. Standing behind the cocoon looking upwards. 2. Plywood sandwich joint. -

Day 3 -

3. Top View. The 4 clamping elements attached on I-Beam. 4. Clamping element (Counter Weight) -

Day 5 -

5 - 6. Group members working on the Clamping elements. 7. Testing out the Clamp (Pulley) -

Day 3 -

Day 2 -

Day 2 -

Day 5 -

IDEAS TO TAKE TO 1:6 - Place clamp at the right position// take the load to the joint

Clamping (Screen Frame)

a

(elastisity)

The design of the clamp joint element is structurally sound with regards to deflection, since the P load of both the structure and the user won’t exceed ± 150 kg. The design also puts the load directly vertical to the centroid point.

a. U shaped scraped wood x 4 (unspecified) b. U shaped scraped wood bolted in between element a. x2 c. U shaped scraped wood x 2 d. pulley whell taken from the axis of a bike wheel e. timber member sloted in between C and joined with f. f. scrap wood to bolt the connecting pieces together g. hanging screen

Further developement of the model could take into account the load that existing members could take and the deflection that could occur. Making sure that the clamping joints are spreading the load equally onto the beam.

Another option to consider is to take the load on to the joint itself, thereby taking all the direct load off from the beam.

ANALYSIS PART #B Bracing and Triangulating

1:1 PROTOTYPE

INSTALLATION DRAWINGS

REFLECTING ON STRUCTURAL FINDINGS If you look carefully at playground structures, you will probably find that most are triangularly shaped. Their physical structure may not be triangular, but some of the components are.

In considering the structure of buildings or devices, I would think about the following: 1

2 Cost

Triangular configuration in 1:1 installation

Strength

How we can use less material while still ensuring that the structure is strong and stable?

The structure must not only support its own weight, but also withstand as much external force as it can, e.g. the users, or wind.

For economic reasons: since the triangle obviously has only 3 sides, it requires little material to make a support, thus minimizing the costs.

Because the triangle does not easily deform and is able to balance the stretching and compressive forces inside the structure.

Overall, a triangle is the simplest geometrc figure that will not change shape when the lengths of the sides are fixed. In comparison, both the angles and the lengths of a four-sided figure must be fixed for it to retain its shape.

Regarding point 2, this diagram shows how a triangulated structure withstands forces.

Triangular shapes are applied in trusses- a structure consisting of triangular units constructed with straight members whose ends are connected at joint.

P P

Showing different elements that required bracing

a

a. hollow section steel pole. 2 jute twine rope are guided through both top side, and 1 through the bottommiddle. b. cocoon seat

b

P

An exploration of household items was done during term 1. What I learnt from this was how to produce triangulated joints that were flexible.

Drying Racks

IDEAS TO TAKE TO 1:6 - Add additional members to complete parallelogram

either...

The beams illustrated in Blue are elements that may need to be replaced with a stiffer beam to allow the structure to be fully rigid.

1. Building the Triangulated brace. Only one member can climb up at one time. -

Day 4 -

2. Inside the cocoon. Steel tube used to guide rope through to connect to the pulley. -

2

3. Initial connection used to connect Cocoon to Pulley. Difficult to reach equilibrium.

1

3

4. A triangular shaped was introduced to keep the cocoon in equilibrium. 5. Setting up the Clamping elements before bracing was introduced. -

4

5

6

7

6. Building the Clamping Frame element in the workshop. -

8

7. Initial pulley connection inside the Clamping Frame. -

Without repeating the structure, certain elements will remain flexible. The upside-down triangle for instance requires another triangle to form a parallelogram.

Day 4 -

- Day 4 -

Day 5 -

Day 3 -

Day 2 -

Day 2 -

8. The connection in 7 was not strong enough. It was replaced with a fixed steel tube. -

Day 5 -

c

c. this alteration improves the balance of the cocoon.

ANALYSIS PART #C Pulley and String Tension

1:1 PROTOTYPE

INSTALLATION DRAWINGS

REFLECTING ON STRUCTURAL FINDINGS The pulley systems that we explored in the installation was faulty!

pulley

We had imagined the pulley as an idealized, massless and frictionless pulleys, and idealized ropes that are massless and that don’t stretch. These somewhat unrealistic parameters meant that: 1 The rope slides without any resistance over the pulley, so that the pulley changes the direction of the tension force without changing its magnitude.

rope

2 You can apply the law of conservation of energy to the system without worrying about the energy of the rope and pulley.

m sketch of pulley connection

F Pulleys are simple machines that consist of a rope that slides around a disk. Their main function is to change the direction of the tension force in a rope.

3 You don’t have to factor in the mass of the pulley or rope when calculating the effect of a force exerted on an object attached to a pulley system. *tsk

Too much friction..?

What we ended up with

Tension is not the same at every point...?

What we should have proposed

Elevation of installation

Screen pulls up

A user sits in the cocoon

a

a. Small pulley inside the Clamp (Frame), rotating on a steel rod, which is screwed into a flat section of a timber piece. b. As shown in the previous page fig 7-8, a. was eventually replaced with a steel tube, which was much strong. But not as functional as a pulley. c. Clamping (counter-weight). The twine was resting on a piece of steel thread. d. The thread was replaced with a steel pipe in the final iteration.

Screen pulls down

A user sits in the cocoon Weight pulls screen back down when no users are in cocoon

Weight pulls screen back down when no users are in cocoon

IDEAS TO TAKE TO 1:6 - Add a pulley system to allow articulated bracing

c

b

2. Additional tightening of the string added, due to it snapping under the weight of too many users.

1 2 3

Day 5 -

4

3. Me sitting inside the cocoon. -

- Day 5 -

Day 5 -

4. Finished installation. Collage, showing Cocoon in relation to screen and counter weight -

V

1. Clamping element with pulley string taut. -

d

Day 5 -

V

Because the shaped structure in the 1:6 is moving apart, the string provides a good pulling force in opposition. It also allows the structure to fold back.

However in regards to anchoring the building, string has proven to be not so effective. A system of pulleys and weights could be used keep the structure in tension.

ANALYSIS PART #D Structural Stability in Hollow Structural Section

1:1 PROTOTYPE

INSTALLATION DRAWINGS

REFLECTING ON STRUCTURAL FINDINGS

Open Section

Closed Section

Torsion of closed sections Studies have found that the torsional rigidity of a closed section is very large compared to an open section member. Following this, I can only assume the by altering the structure of the beam by cutting into it, making it no longer a Closed Section has caused the member to be very inefficient.

b

By cutting this vertical channel for the hanging curtain frame, the structure of the pipe was completely compromised. Now not only does it try to collaspe into itself, but also its resistance to buckling forces dramatically decreases.

a. U shaped Clamp (frame), sandwiches the pvc pole to the I-beam. b. PVC pole, approx 16mm in diameter c. Wooden plank that fixes the pole to the Clamp (frame) d. Twine rope guided through the frame

c

d

IDEAS TO TAKE TO 1:6 - Torsion/ shear

e

d. Bricks used as a foundational element to keep the poles in its place.

2

3

4 5

1. Fixing up the PVC tubes and Screen. -

The cross section of the plastic tubing in the 1:6 model isn’t a closed shape. This makes the member susceptible to torsion, even when bolted to an additional tube.

Day 4 -

2. Setting up the Screen, before we discovered additional horizontal memebers were required for the screen to move up and down. - Day 4 3. Connecting the second Screen. -

Polyvinyl chloride (PVC) pipe is made from a plastic and vinyl combination material. The plastic is melted and molded into piping. The result is a tube of PVC plastic. As a result of the chemical process (PVC becomes very solid and rigid), PVC is less likely to break during earthquakes. It can withstand pressures that many metals (such as copper piping) cannot tolerate. This is why PVC is the preferred material for plumbing and underground wiring.

Showing location of the pvc poles

a

1

o f PV C ing pi

s pe

M

ak

Day 4 -

4. Bricks were used to keep the tubes in place. -

Day 3 -

5. A channel in PVC tube to allow the Screen to slide along it. -

Day 5 -

To improve on the current jointing of the Beam to Joint, a new bracket element can be introduced, the beam replaced with closed and/or Solid sections. This can greatly help the structure to resist buckling and torsion.

ANALYSIS PART #E Hanging Screens

1:1 PROTOTYPE

INSTALLATION DRAWINGS

INITIAL CONCEPT FOR HANGING SCREEN

Initial model used masking tape.

Prototype used bicycle tires and staples.

The proposal for the hanging screen took inspiration from the first iteration of the foldable joint.

a

USING RECLAIMED MATERIAL

Primary Material

Joinary Material

ycle tires

Zip ties

Bic Showing location of the hangin screen

a. U shaped Clamp (frame) b. Thin pvc pole zip tied to a timber plank. This helps to reduce friction between the twine and the plank. c. A brass hook that helps guide the twine to the right place. d. Twine rope guided through the frame .

b c

m bo Ba

o stick

e Twine Jut

s

d

The primary material used for the screen was reclaimed mdf and plywood notice boards, found in the skip next to the school

An interesting feature of the screen was the combination of various various reclaimed materials. a Sm

RUBBER USED AS A TERTIARY COMPONENT

ll PVC pipe s

Staples

e

e. Bamboo stick tied to adjacent pieces of the hanging screen to keep the overall screen rigid. f. An older variation of e. Harder to produce so was abandoned. g. Rubber tire pieces used as connections between each piece. g

f

Rubber used increase the friction between surfaces

Rubber used to soften the connection between materials

Rubber used as bolts

FRICTION OF MOVING RUBBER

1. Attaching the second Screen to the Clamping Frame. 2. Pulley string being guided into a brass hook -

1

Day 4 -

3

3. Zip tie and PVC tube connection for the Screen -

4 6

5

*direction of movement

Day 5 -

5. Cutting up bicycle tires to be used in the screens 6. Different state of the screens moving upwards. -

Adhesion

Day 4 -

4. Bamboo stick also used as a horizontal element to fix the screen together -

2

Sliding Rubber

Day 2 -

Day 4 -

Day 4 -

Deformation

Tearing

Surface (e.g. Road) Rubber generates friction in three major ways: adhesion, deformation, and tearing. The diagram describes these three components making up the total friction force experienced by a rubber moving across a surface.

After researching the material properties of rubber, I have found that out that both the adhesive and deformation components of rubber friction are highly “viscoelastic”, meaning the amount of friction force they generate is sensitive to the ‘smoothness’ of what it is in contact with, and the speed in which they slide across one another. Additional thought into this could perhaps improve the overall effectiveness of the of the hanging screen, since there was too much friction overall.

FINAL INSTALLATION

Back elevation view: showing Cocoon and hanging screens.

Top view: looking at the overall structure from the 2nd floor window of the faculty

Portrait: Karla sitting comfortably in the cocoon