DUBAI, United Arab Emirates

The Walkable Tower

David Gori, Claudia Corgnoli, Massimiliano Coleschi, Roberto Puletti, Alberto Oelker

“Dubay 2010 ……We are in Dubay, today we decide to enjoy this fantastic skyline, we could enter one of the numerous buildings, rise with elevators and in few seconds arrive to a beautiful terrace with view …..... but today we decide to take a walk rising by foot to the top of one of this buildings, the WALKABLE TOWER, tasting the views step by step, catching every perspective of the townscape and of the architecture itself that we are going through” The Walkable Tower is a completely pedestrian accessible tower. Without renouncing at the traditional vertical circulation ways, like elevators and stairways, we studied a pedestrian rising path that allows to reach the top of the building by foot, curling up between structural blades, gardens, terraces. Walking through the park, one can decide to turn around the building, to walk across the structure basement having a break in the large covered garden placed on this, or to rise with the elevators until the panoramic café and the other services inside, either he can decide to climb by foot the rising walkway until the top. The architecture of the Walkable Tower is deep rooted in the park where is placed, the four structural blades seem to be pulled out from the ground, extracting the green soil and uplifting it overhead at the various levels of the tower along the rising walkways, and into the green hanging terraces and roof gardens. The integration with park is reached since the building is emptied in his basement, so the park comes inside the building establishing a spatial unity with it. The park seems to bind itself at the new architecture, the paths curl up around the structure producing a whirl that rises to the top in various green terraces and roof gardens. The spiral shape of the rising paths is inspired to numerous past and present architecture. Particularly it recalls the Samarra Minaret, the most emblematic example of a walkable spiral tower; the tradition wants that when this monument was just completed the Kalif Mu’Tasim rose to the top on the back of a white moke. Another reference are the Bastakiya Wind Towers like an example of architecture that is able to take advantage from natural elements using wind to contribute at the internal microclimate of the building. The spiral symbolism reminds to the meaning of man ascent upward, at upper levels this spiral became narrow, a sort of helix that reminds DNA shape or infinite. Another intent of project consists in subverting the traditional rules of tall buildings usually conceived with a structural core completely or partly hidden by an external shall. For this project we thought at a structural core consisting in four intersecting steel blades completely visible that became the distinctive sign of the tall emblem structure. The external walkway permit to rise and cross the structure, the visitor who walks on this never have the sensation to enter a building and to be closed inside it, he will be continuously captured by different views, going through the structural blades and soon find himself hanging over the town, along the hanging platform or make a pause in the green terraces and gardens at various levels. This architecture can generate new sensorial perceptions, the green fragrances of the park are taken overhead in the roof gardens, from where one can enjoy breathtaking views on every side. The hanging paths with transparent glass parapets, will give the sensation to walk on the emptiness, over the town. The promenade rises until the top to the panoramic café placed between the four structural blades projecting themselves towards the sky to capture winds. At this level is possible to seat in one of the numerous hanging platforms, tasting a cup of coffee at 120 m. of height. The walkable tower can be defined also a “nude tower” in fact the structure is dressed only with a sort of tape (the rising walkway) that rolls on the structural blades, wrapping and penetrating them. The basement is linked at the soil by a transparent glass shall that is partially enwrapped by the spiral walkway that take from the ground level to the podium. Distributional aspects and functions: The access to the tower from the park, is realized with three access ways that run between palms and lawns and take in a large covered garden with a central fountain placed at ground level under the podium level. The tickets kiosk is placed along the principal access way to the park, while more separated are placed the toilets services. From the ground level garden starts an external helical ramp that take to the first level roof garden and over to the podium. The principal functions are placed in the podium, that contains: the conference facilities spaces organized into a 60mq floor area: the conference room for 100 Persons that eventually can be divided in three smaller rooms, two toilet blocks for men and women. At the upper level is placed the library divided in entrance, front office, internet room, multimedia room, reading room, archives. Both this levels are accessible from the walkway and from the four stairways and elevators that go from the underground to the top level of the café. The pedestrian walkway from ground to the top measures 1300ml and every 100m is interrupted by green panoramic platforms where to rest out and look at the view. The maximum walkways slope is never higher than 8%, and anyway at every level is present an additional mechanical ramp with ascent and descent speedwalks. The underground level has a floor area of 100 m. and contains a 30 cars parking. The entrance at the parking from the existing road is placed in the point indicated from the competition organizing, and arrives at the parking level along a 120 m underground passage that takes under the building basement. Vehicles are distributed at parking places by a round way, accessible at emergency vehicles too. The underground way for the access and exit of vehicles is endowed with two pedestrian ways that take directly outside. The rising way system changes feature just over the podium, where is a large roof garden of 280 sq.m from here the walkway goes across the structural steel blades, with ramps and speedwalks that take to the hanging gardens (each with a 240 sq.m. surface) placed at various levels, every 8,60 m. of eight. In this gardens is possible to rest in the shade of the numerous autochthonous trees and plants, sitting on the long benches that serve also as a constraint for the green flowerbeds that are placed on side at an higher level respect the passage. The panoramic café is organized on two levels for a 150 sq. m total floor area, and it opens towards numerous viewing platforms for a total floor area of 230mq. At the first level of the café is placed the counting device, some service facilities and the disabled toilet, while at the upper level are the toilets and other panoramic terraces for a total of 100 sq.m. Security outflow system: The security of the building is assured with numerous outflow systems. The rising walkway itself can be used as an exceptional outflow easy to run across, in fact its 3 m. width would guarantee the outflow of an high number of people. We have anyway 4 fire resistant staircases with 1,20m large ramps. Two of this can be used normally for daily circulation, while the other are foresaw for an exclusive emergency use. The vertical distribution system includes also four elevators blocks for 8 person each one, fit for disable too. Ecological aspects and green building principles: The building is conceived as an ecosystem where the structure aim to harmonize itself with the environment, and fit his functional cycle with the natural cycles of winds, water, sun etc.. The copious use of vegetation in the numerous roof gardens is useful to create an equilibrium between organic and inorganic shape, and to reduce the temperature of the inside microclimate thanks to the water evaporation guarantee from the vegetation. It is conceived as a live architecture able to capture nature energy, its shape originate from the need to take advantage of natural resources. The sharp spire of the steel blades are fit to canalize high level winds inside their structure and like the Bastakiya wind towers, winds will be used to contribute at the refrigeration of the building and particularly of the podium. The convection motion created by the winds will create a natural flue with fresh air coming naturally downward, driving warm air upward and expelling it. The glassy basement shell uplifts it’s hems like happens in the native’s Tepee leathers, to accelerate ventilation. It’s the same principle of the Egyptian Qa’a and the Iranian wind towers. The water natural element is symbolized in the fountain placed in the middle of the ground level garden. The canalized air fluxes, passing over the water surface, give way heat making water evaporate. The natural refrigeration of the building is reached also through the thermal interchange ground- air. Cooling will be generated by geothermal heat pumps. using geothermal drills placed under the substructures, that utilize the underground cool temperature using geothermal pumps located in the technical spaces at the underground level. This pumps utilize the energies stored in the ground very effectively and economically: the temperature of ground remain on relatively stable level all over the year. Several geothermal probes will be realised in the ground and a fluid will be circulated between probes and heat pumps that with active cooling kit will generate cool for the entire building. The sun energy is captured by the large glassy surfaces of the podium and of the rising walkway parapets, using slender photovoltaic films inserted into the interspaces between the double glass panels. This new generation photovoltaic transparent film in amorphous silicon can be inserted inside the traditional curtain walls with the double benefit to produce energy and to create a transparent screen able to stop the UV radius and heat. The surface that can be utilized for this purpose is approximately 7000mq that can produce from 200 to 400 KW/h depending to the film transparency level . Structural requirements: The tower is about 170mt DMT tall out of ground level and has a base of 60 m of diameter. The underground part it as a structure made in armed concrete meld by pillars. On this structure, rigid enough to avoid differential collapses of the base, are inserted the steel blades that build up the skeleton of the tower and that are layed out symmetrically and regularly in such a way to optimize their resistance to earthquakes and wind action. The blades have a modular reticular structure which satisfies the architectural and structural requirements of resistance and ductility, in order to respect the requirements imposed by the environmental conditions. The Pathway that goes along the sides of the structure up to the restaurant on the top of the tower will be made of steel footbridges and ramps. These will also have a reticular structure so that they can be mounted at ground level and then lifted up and mounted at the level of entire sections of the building. The netlike structure will be coated with steel panels, perforated or glass panels depending on the architectural and function will be paid to the use of coating and to the isolation of the vertical blades, that won’t just have load bearing function but they’ll also be like modern wind towers for the extraction of hot air during the day and of cold air during the night. Inside the blades will also be placed the service of emergency stairways, the air distribution elements and the engine. The pathways and the structures at the base will be coated with thermal selective glass panels that will control the radiations.

Europaconcorsi Beta

The Walkable Tower