THREE THEORIES OF URBAN SPATIAL DESIGN
In the article three approaches are defined for urban design theory such as figure-ground theory, linkage theory and place theory. When the article was reading, it is seen that while some people choose place theory and the others may choose other figure-ground or linkage theory for urban spatial design. However at the end it is obviously appeared that obsessing with one of these theories could cause lack of some points.For example if an urban complex is designed around the linkage theory, it falls short because the product becomes nonspatial and therefore nonexperiental.If the place theory is applied without linkage and figure-ground theory, important connections can be lost and if figure-ground theory is applied user needs and implementation level has problems.
A- Figure-Ground Theory: In this approach urban environment is composed of solid-void pattern. While solid defines building masses, void means that gound, open spaces. The objective of this manipulation is to clarify the structure of urba spaces in a city or district by establishing a hierarchy of spaeces of different sizes that are individually anclosed but ordered directionally in relation to eachother. The most known example is Giambattista nolli’s Map of Rome.Because the systems of solid and void is clearly defined and building coverage is denser than exterior space, so, its believed that building coverage give shape to public opening. Alvar Aalto is one of the architects of this century and he describes the problem of spatial design as one of connecting the form of the building to the structure of the site or of twisting and turning buildig’s facades to create positive exterior space. In this theory, creating positive voids is important using buildings vertical or horizantal. On the other hand, sequence between public, semipublic and private domains are important. Susana torre thinks that getting sequences to work, circulation barriers and gabs in contiunity must be minimized or eliminated.In the context, most cities are built from combination and permutations of six typological patterns of solids and voids as grid, angular, curvilinear, radial/concentric, axial and organic.
Urban solids are categorized under three types. First one is public monuments or institutions which serve as counterpieces in the city fabric. Second one is predominant field of urban blocks and the third type is formed by directional or edge defining buildings that are generally nonrepetitive, specialised forms, often linear in circulation. On the other hand, urban voids are defined under five types such as the entry foyer space as transition points or passages, inner block voids, network of streets and squares, public parks and gardens, linear open space system commonly related to major water features.
B- Linkage Theory: It is highly popular in 1960s and involves the organisation of lines that connect the parts of the city and the design of spatial datum from these lines relate buildings to spaces. Linkage is simply the glue of the city. The important point is to make comprehensible links between dicrete things. According to Fumihiko Maki, linkage is the most important characteristic of urban exterior space. He defines three different formal types of urban space; compositional, mega and group forms. For instance, Kenzo Tange and Norioki Kurukowa study on megaforms. In all three types, Maki stresses linkage as the controlling idea for ordering buildings and space in design.
C- Place Theory: Difference of place theory from other theories is the cultural and human characteristics of physical space. While the meaning of “ space” is bounded or purposeful void with the potential of physically linking things, it becomes “place” when it is given a contextual meaning derived from cultural or regional content. The understanding of context of place term begins after 1960s. A place is a space ehich has a distinct character and the role of urban designer is to manipulate form to make space but to create place through a synthesis of the components of the total environment, including the social. The aim is to find best profile between the physical and cultural context and the needs of contemporary users. The perceptiveness of design of places is changing according to time, place and the researchers. For eample; Ian Mcharg brings the term “ecological approach” to design which depends on discovering and working with the intrinsic qualities of given local. In 1950, team 10 promotes the idea of the house as a particular house in a particular place, part of an existing community that should try to extend the laws and disciplines of that community. Besides these; Hermen Herzberger is known as one of the contextual designer and he thinks design is nothing more than finding out what person and object want to be. Kevin lynch studied on the mental mapping process of individuals in the city and he looked at the city in parts in attempt to define a theory of place . He presents rules for the designing city spaces; 1) Legibility: the mental mp of the area which held by the users. 2) Structure and identity: The recognizable, coherent pattern of urban solid voids. 3) Imageability: User perception in motion and how people experience the space of the city. According to Lynch successful urban spaces can be as well as ınquireing these requirements with the elements of urban forms as paths, edges, districts, nodes and landmarks. Gordon Cullen has a different approach for spatial perception with the term “ sequences”. He uses drawings to capture the sensation of movement through space. In addition to the perception of place and the image of space, he implicitly addresses the physic content of the exterior city, the relationship between object and movement. According to his drawings, he brings two dimensional plans to life by sketching perspective sequences that illiminate contrasts and transitions, emphasizing the powerful effect of the third dimension. Another approach to the understanding of context is the work of Donald Appleyard. By his “liveable streets project”, he explores the physical and social complexities of street and developed an ecology of street life. He says people modifies their environment as a defense against traffic. He takes streets as spatial entity.
As it is mentioned above these three urban spatial theoriescan not be thinking separately. All of these should be applied to a urban design projects collectively.