Rongcheng City Hall Square can be considered as a typical Chinese administrative square–ceremonial/memorial dimensions n space. With 800m long n 200m wide (the sizeof 12 soccer field), the center of this square contains a massive grass fieldand one sunken plaza for gatherings and shows, while the space along west andeast side is designed for daily activities with several utilities. Two different functions are connected by landscape to soften the transition. Site for readers pavilion is located on the southeast corner of the square, a triangle shape surrounded by irregular landscape.
There are two driven force to start the design with: 1. How to pass on the publicityn openness from City Hall Square to the building? 2. How to make transition from open square dimensions to human dimensions more naturally by setting up architectural space? Infiltration and concealment are applied as design strategies.
As an extension of the square space sequence, the pavilion needs to be accessiblefrom multiple directions. Following the boundaries of site, building isoriginally shaped in to three pairs of homocentric circles, which open up tothree different directions as entrances, creating three C-shape units, applyingto different functions as reading, kid recreation and café. Intersection amongthree function units forms an open space, so that people can infiltrate throughthe pavilion, maintaining the same openness as the square.
Each unit concludes both indoor and outdoor space, looking similar to Tai Chi symbol. This similarity also reflects from its complexity of space, façade, circulation and experience,joining or separating from each other. Layers of space coated with the reflection and refraction from glass façade are adding up on each other, dressing out the dramatic visual stimulation, triggering curiosity of exploration.
As for floor plan layout,every pair of homocentric circles is divided by 5 degrees, which applies as afundamental module to structure grid, façade, floor tiling design, etc... The steel structure helps roof extends 1.5m further out, creating continuous corridor space by joining even further extended roof above entrances, which works not only as shading structure, but also asconcealment of the building volume, making transition of dimensions more naturally n gradually.
A thin metal fin sticks out 2.6m high above the floor, separates open windows from fixed glass façade, keeping the whole façade minimal. The floor, which is 0.6 higher than outdoor ground, is also sticking out, creating a sense a floatation, which also works as a lovely sitting area for people socializing or even just enjoying the landscape during sunny days.
With application of BIM, design team is able to coordinate more defectively with interior design, façade design, lighting design, and the other teams, assuring finally product is loyal to the original design.
Whole model is combined with groups of façades, roofing, steel structure, interior and more. BIM makes it easier to control even segments of the homocentric circles, sizes of the roof panels. Compared to rectangular steel structure,curvy structure suffers more torsion, but design team managed to solve the issue with the supplier thanks for the help by BIM.
The application of steel structure provides more possibilities to large-span space.Utilities that needs to be hidden behind the ceiling (electricity, water, AC,etc.) takes more space than the space between ceiling and roof, which also requires more support from structure. By considering every requirement, purlinsare designed to support more weight than roof itself. Meanwhile, in order to strengthen the rigidity of rooftop, horizontal diagonal beams are added between every pair of homocentric circles, reducing the section area of every beam while increasing rigidity, to finally lower the cost of building progress.
Readers Pavilion provides another design solution to projects located in memorial space. Instead of exaggerating its own personalities, building is more focus on different relationships between individuals, and between individuals and environment, to create complexity in a more subtle way with combinations of similar units which, however, are slightly different between each other in shapes and functions.
The society also grants Readers Pavilion nice reputation. Thanks to its flexible adaptability in shape and functions, the client has duplicated one of three units and located it on northwest corner of the square as a Beijing Opera pavilion. The typology meaning within deserves further study, from structure, MEP, prefabrication, to more systematic workflow.