Monday, March 7, 2011

Computational design...

The arrangement of the dwellings in the slabs will be organised by optimization using grasshopper/geco/ecotect. The initial model is using a couple of parameters that can be changed for each layer.

Divisions along x-axis
Divisions along y-axis
Density

The model is very basic, it can be found here. It creates a isotrim from a loft (the total area). The faces are isolated from the isotrim, and are reduced in a random way, with use of the RandomReduce feature. The density in % gives the amount of the total faces that have to be trimmed. beceause of the randomness, the result is different every time.

2 examples of this model:

And the parameters (config 3 and 4)


The most important result is the Total Density. This gives the percentage of open space. The lower this percentage is, the more economic the result is.

BUT.

The daylight is obviously the big critical factor. So globally our plan is to fix the density, and to find for a given density the most optimal daylight. This modelis unsuitable, because of the randomfactor. The optimization with an evolutionary algorithm doesnt work good, because not all properties of the model are inherited. Some change randomly with every new try. The computer is not able to converge to an optimum because of the noise that the random element causes.

A more sophisticated model is not based on subdivisions any more, but on the number and the size of the connecting streets. It still uses RandomReduce, but the model is done in such a way that an algorithm can be implemented for this function. A result of the new model:



This is interesting, because we need to find an algorithm that is progressive in some way.
Lets suppose that we have a model with only one layer and 9 breps (houses). The layout for the plan looks like this (without streets).
Lets say we want a density of 60% on the ground floor. In that case, 60%*9= ~5 blocks have to be rendered. When we do not use the RandomReduce, 4 blocks have thus to be reduced in another way. Lets use the brute-force strategy. It culls 0,1,2 and 3. It looks like this.
After calculating the result for daylight, it goes on with the next option: 0,1,2,4.


the optimum probably is:


In this case the program will have to try (9 nCr 4) = 126 times to be sure it has found the optimum (correct me if i'm wrong, math's a little hazy now...). In a 3x3 grid it is still possible, but in a 8x4 grid (32 breps, 601080390 possibilities) it is just impossible to calculate it like this.

So in the end we'll have to go back to an genetic algorithm. The first generation is randomly generated, the next generation will have mutation of no more than, say, 10% from the best shots. Right now I have no idea how to do this...whatever I can think of needs a lot of scripting.

Sunday, March 6, 2011

As a result of the urban analysis we decided to use the stadium as literal catalyst for the development of the area at the same time as we provide this new stadium of a nice urban context related to the accesses, circulations and interactions with the new neighborhood.
The formal solution to achieve the goal came from an urban cladding approach following the gesture of the integration housing-stadium. The urban fabric wraps the stadium.
This leads to two main directions in the process to make a coherent design: the functional (from an organization point of view) and the visual (from the skin point of view).


In respect to the skin:

The skin will not only deal with the visual challenge of the gesture but also with the energetic performance.

We can identify some preliminary goals or restrictions for this skin:

1) It should be understood as 1 skin wrapping the building which changes its role in relation to the housing (roof or façade) but always continuous.

2) A transparent skin to allow the maximum of light in the living areas.

3) The subdivision of the skin should emphasize the twisting gesture.



The fact that this urban fabric is considered as a whole should be used in the energetic way as well. We identify the possibility of creating a microclimate under the skin.
We can identify two performances of the skin according to its position in relation to the housing:

1) The horizontal one serving as roof of the low-rise neighborhood. Improving social relations in the outdoor space by creating a more comfortable atmosphere, a microclimate.

2) The vertical one serving as the second façade of the housing.


Both deal with sustainability from the thermal comfort point of view.
To determine in which way the skin deal with the comfort and energy saving we identified two main paths:

1) Using the second skin behavior in winter and summer

2) Focusing on one specific problem: winter

The first option requires a lot of adaptation. When having a transparent second façade, winter comfort can be quite achievable but we have an overheating problem in summer. This problem can be solved through shading the second skin and ventilating the cavity. In this case, the double façade would also be energy efficient in summer but paying a price for it, the transparency. It is important therefore to evaluate the need of the second façade in each situation.
By analyzing the site more carefully, we can see that the overheating problems in summer are not as problematic as in the more inner parts of the city. Because of being next to the water, the evaporative cooling effect takes place.
During the day, the sun heats up more the land because of the lower thermal inertia in comparison to the water. Because of that, the air over the land increases its pressure which provokes a displacement of the high mass of it towards the water. The pressure difference provokes that the cooler air above the water move towards the land provoking a cooling wind which helps to reduce the temperature in the area.
Because of this, it is reasonable to focus the summer behavior in the ventilation of the skin. This way, the natural ventilation of the housing could be achieved in a more direct way.







Winter performance of the skin: microclimate


PERFORMANCE OF THE SKIN: Improving comfort and energy saving in winter, in both the urban and the building scale allowing a maximum of light through it.




Summer performance of the skin: ventilation


ADAPTIVE SYSTEM: Focused on the opening of this skin for maximum ventilation.


Possibilities of the subdivision of the surface:




We can see that the division of the surface in one direction or the other has a lot of influence for the emphasis of the twist.
In the first two examples we can understand the subdivisions as the. The lines can be understood as the generators of the twist. This is not absolutely true because the two curves have different lengths and curvatures, but the gesture is visually emphasized.
The perception of the twist increases proportionally to the number of lines.
In the last two examples, the longitudinal subdivision talks more about the divisions of a given surface The perception of the twist gets more lost the closer the lines come.
From a street point of view, the twist will only be more visible when the surface responds differently to light, which will not really happen with a transparent material.




Possible solution: Transparent strips which can rotate independently achieving an adaptive ventilation.


Friday, March 4, 2011

To all of our dear followers that were eagerly awaiting updates: apologies for the long time since the previous post.

After the analysis we made a masterplan, mostly based on the first part of the analysis (that you can read a few posts back). Keypoints in the plan are the many connections with the area west of the Stadiumpark, that is now completely blocked out by the infrastructure. The public parts of the stadium will mainly be oriented towards the west.




After a lot (!) of discussion and sketches on how to proceed, we decided to go with a very literal interpretation of the masterplan. The housing structure of Rotterdam-Zuid will be continued towards the stadium (see masterplan), and then wrapped around it. The stadium becomes a social housing project. A very literal continuing of the urban fabric. We believe that thit is a clear statement, after all design is politics.




The square opens up towards the stadium, and the space underneath the overarching twists is a very interesting public space. When there is no match going on, the space under the stands is part of a connection between east and west. There can even be a bicycle-path.


Because the curved shape is quite complex, we decided to split it up in 3 parts: the ends ("slabs"), the twist, and the vertical housing. In the curvature they form an unity, but thus far during the progress we treated them more or less seperately.

The slabs consist out of a high-density low-rise social housing complex. It is three layers of housing, and it is one of the subjects for the computational design (later more on this subject). Bottom-line is that it should be as dense as possible, with as much daylight in the bottomlevel as possible, with as much coherence with the rest of the "ribbon" as possible. These are two of a few partly parametric, partly random determined (density, size, number of subdivisions) configurations of the dwellings. The reference from Madrid (couple of posts down) may be more clear now.




The twist is a transition area that is a real challenge. The architectural language of the twist, combined with the slab is quite strong, and we don't want to do too much concessions. Horizontal floors are mandatory, but by creating curved facades, it is in our opinion possible to keep the twisting lines in. Here is an visualization of the twist and the slab+twist seen from the waterside.



The third part is important. It is where the conflict between the different scale (housing and stadium) is most evident. For the largest part we want to seperate the trafficflows. Only some big plaza's are cut out of the housing skin. During matchtime (approx. 3% of the time) are these plaza's closed down for the 'villagers'. Or, what is more appropriate: The village is closed down for the hooligans.



Potential problems:

- The roofstructure, on which we did not yet decide :x The support can ruin our cavity, or can penetrate the unity of the facade. The longer we postpone decisions about the roof, the more it will be problematic later on.
- The twist. We have a clear visual in mind. Chances are that we need to do concessions. It is such an unconvenient form for a building, that our layout of this area should be really well done.
- The daylight in the housing zone. High density does usually not compute with this.
- The acoustics and the vibrating and trembling of the stadium in relation to the housing.
- ...enough more. There is a lot of things to be solved. But we feel like we are getting somewhere.


Monday, February 28, 2011

Thoughts on Rotterdam-Zuid Part 2

Image source: De Urbanisten, De veilige en goed ingepaste hoofdwaterkering in Rotterdam

Rotterdam is split in two halves by the Maas. This river is not only a big source of income for the city, it is also a threat. The Global Warming is causing a rapidly raising waterlevel, that, according to some experts, will threat the city with floods. Rotterdam is protected by the Maeslantkering, a big reconfigurable structure that closes during heavy springtides. Recently has been concluded that this structure has a pretty big fall-out percentage. This is an extra danger for the city. The dikes are not on the edges of the Maas. Big pieces of land that are outside the dikes are used for industry, agriculture, housing or whatever functions.





1. Doklaan
2. Hilledijk
3. Stadionpark

Due to the rising waterlevel, an advise has been given to raise the dikes. This is quite a big intervention. A dike a little bit like an iceberg: the biggest part is underneath the surface. To raise the dike, the slope of the structure has to stay the same, so the amount of volume that has to be added is more than it seems at the first sight. With the raising the dike, there also arises a physical barrier. Currently there is a project going on in Rotterdam to create multifunctional dykes, the so called 'trapdijk' (terrace dyke).
The stadium has to be built next to the dike. It can be used as a dyke, or be built on the dike. When the whole stadium is designed as a ringdike (left), the barrier towards the sportpark is removed. However, the barrier towards the surrounding neigbourhoods is a potential danger. Another option is to raise the current dyke and incorporate it in the stadium





Friday, February 25, 2011

Streetsoccer in Rotterdam Zuid (Hillesluis, Bloemhof, Afrikaanderwijk)




Superstadium (Shanghai) + Social housing (Hillesluis)






Wednesday, February 23, 2011

Thoughts on Rotterdam-Zuid Part 1



Building a stadium is an urbanistic matter. Rotterdam-Zuid is regarded as one of the worst areas in The Netherlands. Recently it has been in the news because some important opinionmakers called it the 'cleanout drain' of Holland. Lets have a look at the figures of the neigbourhoods of Rotterdam-Zuid, that we took from the website of the municipality. This gives us the opportunity to compare with the rest of Rotterdam.




The weak areas are clearly visible. They are pretty close to the site of the new stadium (dashed circle). The 'empty' area west of the site is filled in with railroads and a big road. Its remarkable that the most problematic neigbourhoods are west of the railroad, and the better ones are east. as you can see there are two connections from east to west, the north and the south. These connections are huge fly-overs.





The segregation of the different areas in Zuid is, in our opinion, a bad thing. It becomes harder to get out of the neighbourhood, and there are other problematic effects, such as stigmatizing and redlining. If the most problematic areas of Rotterdam really want to benefit from the spillover effects a new stadium, there has to be a better physical connection.





now the barrier of the trainstation is evened.But a second barrier arises, the big 4-lane road that connects the centre of Rotterdam with the highway.



The connections are very important. Not only for social-economic purposes, but also for the logistics of big events. With good slow-traffic connections, it becomes more easy for people to park their car at distance. The stadium itself should also be connective. De current masterplan for the area seems to be a design for succesful people. Expensive free-market appartments have been built alongside the Maas, a cinema, shops, parkinggarages. Luxury right next to the poorest areas of Rotterdam (Afrikaanderwijk, Feyenoord, Hillesluis). In our opinion, the stadium should be used to overcome segregation, not enhance it. Something like this:

to be continued...