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Lightplan for the Heizel plateau, Brussels (B)

The project of 'light_scape(s), displacement maps' is a study for a lightplan of the 'Heizel plateau' in Brussels, commissioned by the Belgian electricity producer and distributor Electrabel_Sibelgaz. The study covering both a research for operative tools to conceive light in the scale of the city as well as the conception of light as a dynamic vector of the urban. The project enlarges the starting point, a light study for the Heizel stadium, to a more general reflection in order to integrate light not as an autonomous device but rather as an important vector of the public realm. The project therefore capitalises not only on light as a spatial device ( light_topography ) but also as a temporal device ( light_urbanism ) broadening the traditional scope of public lighting by establishing a remarkable urban landscape for the area of the world exhibitions 1935 and 1958.

commissioner's motivation: //

The workshop was initiated by Electrabel / Sibelgas and was presented on 20 January 1999 with the new catalogue of public lighting infrastructure for the Brussels district. The organisation of the workshop shows the will to shift from the usual way to think about light, taking the functional aspect, as the security criteria, as well as the rather differently orientated recent examples of public lighting in France or Germany into account. Actually the common use of public enlightening in Belgian cities has so far led only to a uniform landscape, undifferentiated, all contrasts being bathed and blurred by an orange fog, a phenomenon well known for the experience we have all of highways surrounds, preventing any attempt to put forth a site and its buildings.

con.texture: //

The Heizel plateau found its identity through a series of happenings, such as the two world exhibitions, important sports events and commercial fares. Currently, there is an important discrepancy between the landscape offered by the Heizel plateau and the millions of visitors it generates, particularly for events such as the forthcoming Euro 2000 and "Brussels, European cultural capital - 2000". The project therefore uses light to emphasize the exceptional character of the site in the Brussels urban landscape. Thus, Lightscape(s) integrates the Heizel lighting project in the scope of the city. The study is to be understood as a complement to the current works while integrating lighting devices that are active during the day and during the night. As a consequence the project offers a global approach exploring the possibilities of lighting as generator of urbanity, illustrating the potential cultural dimension of public lighting.

displacement maps: //

'Displacement maps' deals with the dynamic visualisation of light in the urban scale in order to create an operative working tool rendering light as a matter defined by the parameters of intensity, colour and temporality (temporal cycles).

The starting point of the project, the application of contrasted ambiences in colour and intensity on different programmatic entities of the Heizel plateau, exploit the potential of light either to generate strong images, to identify a remarkable landscape, and on the other hand, or on the contrary to erase whole parts of the landscape. The conception of the light_plan directly depends on a general vision according to light as a matter based on contrasted devices. The project therefore works out the creation of diversified lightscapes throughout time-cycles flattening into one single device: landscape -structure, activity-programs and flows-infrastructure.

The lack of working tools to visualise and to verify the hypotheses on lighting at the urban scale has lead to the exploration of computer software such as the ones used by the cinema industry, allowing dynamic simulations. The alteration of modelling software to 'dynamic functions' therefore opens up to work with light, immaterial and variable matter, in a global and processual manner evolving in space and time. Thus, the use and conceptualisation of functions, called 'displacement maps' have out ranged the classic use of the computer tool, led to its active integration in the process of creation itself and showed the ability to work with light as an urban vector.

Throughout the quadri-dimensional visualisation of light, the animation outlines the specific possibilities of light, displaying light not as a static material but as a dynamic substance. In the first stage, the grid deformations correspond to the variations of luminous intensity, in the second stage, it shows the variations of intensity according to time, the various cycles of activity (ex: the stadium during a soccer game…) , finally it shows the contrast between a work on colours on the site and the existing orange fog.

INTENSITY - The grid deformations correspond to the variations of luminous intensity. The existing situation was established from measures of light intensity on the site. In this situation, the only ' extruded ' element that outgrows the uniform orange fog is the Atomium. In the project, along with the existing situation, other points are extruded, accentuated, by variations of the light intensity, augmented or dropped while forming specific spatial configurations, light-scape(s).

TEMPORALITY - the grid transformations show the variations of intensity and colour evolving in time, according to the various activity cycles (ex: the stadium during a soccer game…) In this manner the light plan enlarges the habitual way of enlightening as an on/off device by exploiting the variation of light intensity throughout time, continuously forming new configurations or temporal lightscape(s). The work on the time cycles transposes light from a structural device to a vector of event and interaction.

COLOUR - The site, actually immersed in a uniform 'orange fog', is transformed into a diversified landscape outlined by the use of colour. The exploration of the RGB - code related to activity exploits light as an additive matter, where the white light corresponds to highest density of information and in this case to highest activity, and it's decomposition to the spatial device of the 'light_topography'.

The dataprocessed scapes of the light_plan use the variation of intensity and colour throughout time in order to create changing lightscape(s) according to spatial configurations - structure, activity - event and individual uses - interactivity.

light_topography: //

The creation of a 'light topography' by the variation of intensity and colour throughout the specific enlightening of point, line, surface and interface exploits light as a structural device within the urban.

The creation of a 'light_topography' stands for the spatial organisation of the light plan structuring the site throughout the devices of point, line, surface and interface. The 'points' stand for the enlightening at the scale of single constructions; the lines for infrastructure, the surfaces for entire equipment, and the interfaces for places of exchange. The overlaying of this conceptual grid transfigures the idea of the universal exhibition masterplan in 1958, nicknamed 'la vache' (the cow) to a general approach. The urban layout juxtaposes in an open manner independent programmatic entities, each one tuned to their own temporal and spatial logic by forming a continuous contrasted environment.

This structural approach of the project is the result of an urban analysis synthesizing each of the upper schemes into a specific 'light_topography' of contrasted enlightening. The variations of luminous ambiences are achieved while emphasising or blotting these different entities, shaping the base of the entire projected landscape. The merging of these different spatial systems throughout time forms the final design of dynamic light_scape(s). (light_urbanism)

POINT: the localisation of the points of light and their respective merging lead to four landscapes, called sequences. The idea of sequences consists in the identification of the main spatial configurations of the site and their dynamic and specific perception. The 'runway', the 'highway', the '35-58 axis' and the 'skyline' form the basic structural skeleton of the landscape.

Sequence 1 - A12- runway Heizel, the chain of punctual coloured lights outlining fragments of buildings (logo-like) forms a sequence along the gateway from/to the city, the A12 highway. The variation in spacing between the lightning points on the Heizel part of the road would strengthen the acceleration / deceleration feel. The relation of light, movement and speed lead to the term of 'runway'.

Sequence 2 - the ring- heizel highway, two luminous logo signs representing the palace 5 and the stadium identify the main infrastructures of the site towards the ring, main access of the visitors. The lower level of the ring does not allow any other visual contact with the site apart from these high perched luminous signs.

Sequence 3 - bld. du centenaire- 'axis 35-58', the renovation of the Atomium's original lighting and the enlightening of Exposition hall 5 would outline the monumental 'axis 35-58'. This 'urban furniture' is one of the mature elements structuring the inner organisation of Heizel plateau.

Sequence 4 - Houba de strooper- skyline Heizel, the enlightening of a series of buildings (Stadium, Océade toboggan, planetarium, Atomium and the church of the Sacré Cœur) would form a real skyline acting as a main façade reflecting the great diversity of the site, while benefiting from the plateau topography.

LINE: The treatment of the intermediary spaces between the site's main features lead to the design of a path connecting all the existing flux with their obligatory landing point, the parking lots. The decrease of luminous intensity on the parkings strengthens the contrasts between the different entities. This loss of intensity is compensated by a treatment of the ground, for instance with colours or materials reflecting light while tracing a new route through the various fragments. The use of the path as a graphical support strengthens its orientation and information purpose. It illustrates the research on differentiated materials associated with the treatment of light. This intervention is based on the use of reflectors, phosphorescent paints and reflecting coatings.

SURFACE: The work on the huge building complexes works out a method offering the possibility of an 'independent' enlightening of the different programmatic entities. This lead to a flexible light plan exploiting the existing contrasts and opposed logic throughout time. The line, and the surface illustrate the idea of 'la vache', the cow. The equipment and the outlining of their luminous intensity lead for example to the treatment of the stadium as luminous objects. The use of coloured light, corresponding to the public's access gates of the stadium, to lighten the bottom of the stands, uses light as a colour code. A luminous crown encircles the stadium in the form of a scrolling ribbon, programmable and regularly updated, carrying the information from one point to another, covering the entire surface of the site.

INTERFACE: The interfaces are user influenced places of exchange interconnecting the Heizel plateau with the surroundings. In this case they all correspond to parking lots where the parking S forms an interface with the city, parking E with the A12 periphery and parking C with all the interconnected highways (Ring). The operation on Parking C (10.000 cars) treats the main access as a large scaled landscaped intervention. The existing concrete blocks are coated with a phosphorescent paint, producing coloured area daytime, and a luminous landscape at night. The phosphorescent painting reacts to the individual use of space giving an enlarged dimension to the idea of interface as a user reactive environment.

light_urbanism : // fix_variable_reactive

The concept of 'light_urbanism', articulates light as a temporal device synthesizing fix enlightening - structure with variable interventions - events and reactive supports according to the inter.relation of the individual. 'Light_urbanism' therefore exploits the double meaning of light, opposing to intensive urbanisation forms, temporal 'light' devices.

The inter.relation between light and activity leads well beyond de static on/off option, shaping the landscape through time with the help of FIX - VARIABLE - REACTIVE interventions. Corresponding to their topography counterparts, fix works with point interventions ( light_topography), variable with the activation of surfaces and reactive with the interface status. These interventions show the possibility to achieve urbanity through 'light' means as well as 'lighting' devices, leading to the double signification of Light_urbanism.

FIX - The fix devices correspond to the four points-defined landscapes and simply works as an on/off system, giving minimum and colorful lighting. They form the structural and fix feature of the dynamic landscape.

VARIABLE - The Variable light devices correspond to the scale of surfaces evolving through time in colour and intensity according to the activity cycles off the respective equipment. At the minimum level of activity, the equipment is defined by low intensity but colorful light and at maximum level by high intensity bright white light. At all the intermediate levels corresponds an intermediate intensity and colour. In the project, the case study was the stadium equipment, lighted at minimum level by a red luminous scrolling ribbon and the 'color-code' light at the bottom of the stands, and at maximum level with the same light devices augmented by the four high intensity light pots. In this manner the project transpose the RGB-code of light, white light being the synthesis of all colours, to the urban scale interrelated to density, event and activity.

REACTIVE - The reactive interventions take into account the status of interface of the places they process by transforming the inputs happening on the site or in the surroundings of the place into lightening devices. The interrelation of activity; flows .. with light therefore define an anticipative relation between the urban space and the individual. The intervention of the parking C, for example, with the phosphorescent blocks absorbs light information (daylight and artificial light) in order to become itself luminous, but in such a way that every parameter is reflected by the intensity and the localization of emitted light. In this manner a single car passing through the place produces a temporary visible (vanishing) path on the blocks. The time lag occurring between an event, an information and its total disappearance is conceptually accounted as 'Hyper_trace'. This 'hypertraces' becomes the expression for the individual shaping of space.

conclusion: //

Generally speaking, the project on the Heizel site demonstrates the potential and the diversity of ambiance achieved through light devices and proposes a refection on the urban challenge that light represents in the city scope. The light is no more considered as an autonomous device, as generally processed in an over-pragmatic approach, but much more integrated to environmental reflections. In its approach, the project is a research for another form of public lighting outgrowing the simple question of a practical and technical device of security but becomes much more like a polysemic medium broadened to the urban scale the cultural dimension of the public realm.

LAB[au], M.Abendroth, J.Decock, N.Mestaoui + K. Pecheur, P. Desmedt-Jans, 1999.