The rapid development of urban areas around the world has reached alarming dimensions and brutal living conditions. VertiCity is a prototype that aims at spatial diversification and the improvement of quality of life in densely populated areas. Porous, vertical structures with interwoven spaces that unfold in narrow locations and provide spaces for relaxation, social interaction, unplanned communication and all residential functions within a connected vertical system are explored. Aim of the research is the development of a practical parametrical design method for optimized complex porous structures.
Starting point of VertiCity are two apartment towers like the apartment buildings Lake Shore Drive 860-880 in Chicago, designed by Ludwig Mies van der Rohe in 1952.
The two steel frame towers are one of the first residential high-rise structures. We have chosen these structures as the basis of our research due to their flexible and plain configuration.
The first step is the loosening of the stacked apartments. For this purpose the two cores of the towers are understood as “magnets” that are able to attract units from the opposite tower and dissolve in this way the respective system of apartments. A spongy, porous structure emerges between the two apartment buildings.
Randomly emerging holes within the porous structure are understood as location for bridge-like public spaces. Within the identified holes elongated volumes are generated whose section and orientation depend on the properties of the holes.
The entire structure of the porous residential towers with bridge-like public spaces is optimized according to different targets through an iterative algorithm: maximum of porosity, minimization of loss of floor area, maximized view, maximization of sun light penetration, and structural efficiency. All targets can be numerically described. In this way a so-called “fitness-value” can be identified for each target. By means of a mathematical function in which all fitness-values are combined the total fitness of the solution is calculated. In a short period a large number of random variants are generated and their fitness tested. The individual variants will be improved through a constant process of selection, recombination and mutation until the total fitness of the building is maximized.
Several optimized results are further explored, their spatial and structural potential analyzed and developed: Smaller holes in the porous structure are glazed and function as buffer zones. During summer they are fully ventilated, in the transitional period they add to the passive thermal gain and in winter they improve the surface-volume-ratio.
The public bridges are connected through escalators, staircases and ramps and form a kind of promenade, a vertically folded public park.
Several apartment units in the inner of the structure with disadvantages in regard to sunlight penetration and outlook are rededicated to collective program: cafes, indoor playgrounds, yoga-centres, community kitchens or neighbourhood libraries can be located in these units.
A second skin is netlike pulled over the inserted bridge elements. In several spots the skin is designed as a translucent membrane that functions as wind and rain protection. In open stitches Windbelt Power Machines are installed that generate electricity.
The vertical public space offers spare time and recreational facilities and lush planting. Together with a large number of private gardens and loggias a vertical landscape emerges, a local recreation area and green lung for the neighbourhood.
Improved residential towers like VertiCity can be arranged relatively close to each other on a shared podium. The vertical public spaces are connected on different levels and form in this way a netlike landscape structure within a densely populated area.