Final Presentation

View more presentations from erikrogier

We won!!

cheers for XXL victory for India!!

Breaking news!

Great news for Prashanth, the structural designer of WAN. India won the semi final of the world cup cricket against old rival Pakistan. The final will be played next week in Mumbai with opponent Sri Lanka. Together with opponent Sri Lanka, they will play the final in Mumbai next week.

making history.

"Light cladding"

2 scales, 2 roles, 1 concept: "light cladding"

For the cladding we have 2 extreme scales to apprach: the large span roof construction and the tiny scale of the housing.

Roof: Transparency is a key requirement in order to get the maximum of light, through the stands openings, in the cavity.

section through stands' opening

Since the cladding of the roof behaves only as a shelter, "a raincoat", efficiency is a key aspect to take into account in such a large surface. Also the concrete roof structure asks for light weight material.

We will use single layer ETFE foil to meet the requirements of transparency and light weight, and take advantage of the large span possibilities of the foil to reduce detailing and facilitate water tightness and water evacuation. This will be done by spanning the foil along the radial concrete beams and achieving the tension needed through pretensed strips in an arch shape. The self-cleaning property of ETFE also adds to the efficiency aspect.

Housing facade:

The concept for the housing facades is to get a maximum comfort by increasing daylight.

Adaptability_1_The openings will be placed according to the daylight optimization analysis, which is specially relevant in the 3-layer housing (horizontal and twisting parts).

In the vertical housing, the main light source comes from the external surfaces of the ribbon. In the north side, this surfaces will consist of a large glass window in the edge of the housing box to allow a maximum of light inside.

Adaptability_2_In the south side we will have reconfiguration possibilites for energy saving in different climate scenarios still allowing a maximum of daylight. 3 layers: glass, sun shading and single layer ETFE.

The ETFE will allow a maximum of light (95%). These top to bottom ETFE windows will be very light and easily opened according to the user's will. The ETFE will have the same tension principle as in the roof but in a much smaller scale. This shape will help against the windload both when being closed and open since they will fold in pairs avoiding a concave surface against the wind.

operability of second ETFE skin

housing south facade

Finally, the roof works!

The massive 'light' concrete roof finally performs well enough to be built!! After much iteration of curvature, height and sectional sizes, it was wonderful to see all the hoope forces acting in the structure. The maximum deflection achieved now, 316mm, is within the permissible limits for such a large span structure. The stresses are also well under control.

As u can see all the compressive stresses gradually increase towards a maximum towards the 'inner hoope'

The first image above shows the roof with a more elliptical inner ring, which resulted in a deflection of 850mm, after raising the height of the roof from 7m to 12m. A slight change in geometry, as suggested by Andrew, to make the inner ring as close to a circle as possible, and also a slight change in curvature, reduced the deflection to just 316mm. What a drastic change in deflection by only a small modification in geometry!!

Daylight on ground floor and floorplans

As you can see, the different dwellings on the ground floor have different lightsituations. It is important that the dwellings make as much use as possible of the potential daylight in their area. In order to achieve that, our strategy is to cluster the dark functions in a box. This box can be placed in the dark spots. The living room will then always be in the lighter area.

pseudo optimizing

After deciding on doing a more ´geometrical´ optimization, it was more easy to get some geometry with pretty good results in the daylight analysis. The first and second floors are added by trying to achieve as much overlap on the floor beneath as possible. In this image you see the projection of the 3rd floor on the 2nd floor. It is optimized, so there is as little overhang as possible with the given grids.


The geometry (including windows to the southside):

Leaving Ecotect

Another strategy would be to seek for configurations that have as much connection with open space as possible. In other words: minimize the amount of blind walls.
For one island, this goes like this:


Without the streets taken into account (I acknowledge this is an err, but i need to figure out a way to 'discount' the walls facing a street, because the streets are so small that they block out a significant amount of daylight) it looks like this:


As you can see, Galapagos is more or less able to seek in the good direction. It generates better options as you let it run longer. This is the merit of the 'progressive seek algorithm'. Its very satisfying to see that it actually works.


And with the streets added and a quick daylightfactor calculation:



the result is not optimal, in a sense that there are other configurations that have a better ecotect daylight result. But still it is a good option, that follows from common sense.

Galapagos-Ecotect

I have a Celeron Dual Core T3000 1,8 GHz and 3 gig ram. This is way too slow too handle the optimisation of the flat part. The calculation of ecotect is quite heavy and requires more power. Our ´progressive seek algorithm´ does not have much impact on the results, because the population-size is too small. But we cant make it higher because the calculation-time would become too high. Days or even weeks.

Here is an movie of the seekingprocess of only 4 of the 16 'islands'. It is speedened up 9 times (!). so the real proces took half an hour.

As you can see the population-size is low, and the optimum it finds is a clustering of dwellings. This is not the optimal solution, we can tell by common sense. Also earlier calculation with a higher ecotect-grid resolution, show that the optimal configuration for 2 of the blocks is this:

Compared to the optimum of the movie, this looks like its more optimal: more light enters the built space, because there are more surfaces facing open space. This shows that, with a high resolution grid and a bigger population size, the optimization works. But we lack the computational power to do the calculation...which is a shame. The bottleneck is the slow calculation of ecotect. Which is really frustrating.

Daylight analysis

To analyze the amount of daylight in the cavity, we calculated the model in DIALux. These results however were very much too high, when some research didn't solve the problem we decided to do the calculations in Ecotect. The first result looks realistic and promising. More results will follow.

daylightfactor in Ecotect

PRESENTATION

Interactive Presentation, post your comment during or after the presentation. WAN

Masterplan

Houses wrapped around the Stadium

Floorplan, Walkaround and Circulation Schemes

Openspace: Public Furniture and Stands

Optimizing Geometry: Floorspace and Daylight

Facade: Sustainability, Ventilation

Construction

End

Workshop

nvm

Educated randomness

This is a model for the facade in the vertical part (that will gradually dissolve in the twist). It contains the frames for the ETFE elements. The articulation of the facade can be tested with this model. It is possible to make an amount of predefined columns, the vertical configuration (in excel), out of which grasshopper generates a random looking system. It follows the curvature of the envelope that can easily be assigned out of rhino (or directly out of grasshopper of course). The open spaces are placed at the height of the walkarounds.

This model gives us the opportunity of testing different visuals, being able to make quick changes in the relation between facade and what is underneath it because it reads directly from excel.

Configuration 1

Configuration 1 different random seed
Excel column configurations
Configuration 2
Excel sheet:
Grasshopper model

Thoughts on Construction

After a lot of debate with Andrew last friday, we had a thorough look at the roof and the construction of the bowl itself so that it blends well with the main concept. The idea that the housing ribbon behaves as the main support for the stadium still remained, both visually and structurally.

The steel truss system was discarded as we wanted to see the bowl with the roof as a heavy object supported over the housing. So we are trying to investigate a light weight concrete roof. First thoughts were to puncture the roof along the same lines as the housing, with regular divisions.

But on second thoughts we decided to make this as a gradient of solid and void with more solid towards the support and gradully reducing to void towards the end.

Now the bowl and the entire system for construction-

Enhancing on the idea of the neighbourhood supporting the stadium, we propose to have bridges connecting to the tribune from the neighbourhood at regular intervals. This serves both as functional bridges for access as well as structural support to the main stand, with tapered columns supporting the bridges towards the bowl.

The sustainablility consult yesterday encouraged us to investing more on daylighting in the atrium like space all around in between the neighbourhood and the tribune. Thus we decided to split the stands at regular intervals to have light streaming in from inside the stadium.

Let see if this system could be made a little irregular to go with the housing pattern in the ribbon.

Another important thing to be thought about is, if the field has to be slid out, this demands a column/ support free zone for almost 70m along the east side. So we need to check how much free span we can do with this system.

Daylight analysis

Daylight is an important issue in our project, daylight is an important parameter for the quality of a space. The ribbon of houses around the stadium only have on facade which is exposed to daylight, therefore the depth of the houses is limited. The void behind the houses and below the stands is more problematic in terms of daylight but also has a high potential. This is the space we want to analyse with DIALux and Radiance. 

Daylight can enter the void in three ways: - by the openings in the houses - through the opening at the top between the houses and the third ring - through the slits in the stands.

The use of certain reflective materials, the number and the size of openings will directly effect the amount of daylight in the void. With this analysis we want to  know what the relations are between the geometry and the amount of daylight in the void. 

preliminary result from DIALux:

isolines in candela of the floorplan

isolines in lux of the floorplan

some examples:

• Sunlight: 100 000 - 130 000 lux
• Daylight/indirect sunlight: 10 000 - 20 000 lux
• Cloudy day: 1000 lux 
• Office: 500 lux
• Full moon: 0,1 lux