With a line of wooded hills at its back and fl anks, its form reflected in the still water of an artificial lake, it stands as a calm and contemplative place in which to observe the
rituals of cremation and honour the dead.
Designed by Toyo Ito in collaboration with structural engineer Mutsuro Sasaki, this work continues Ito¡¦s explorations into spatial ambiguity, from his Serpentine Pavilion of 2002 in London, in which he dispensed with conventional categories of structures and infi ll, to the I-Project, a botanical garden in Fukuoka, Japan, where he fused landscape and interior spaces with a seamless, fl owing series of reinforced concrete shells.
But with this building, the Meiso no Mori Crematorium (it means Forest of Meditation), he has taken the game one notch up. For here, in a park-like cemetery setting at Kakamigahara, in the Gifu prefecture of central Japan, the master architect
has sought to dematerialize all sense of formal structure by floating over the landscape a vast undulating shell in which to shelter the ceremonial functions of the crematorium.
And though the roof appears free in form it was realized through rigorous structural analysis. The building replaces a former crematorium inside the cemetery. The idea began with a series of simple sketches of a fl owing reinforced concrete shell which combined a billowing structure and columns struck as a single, uniform surface. It was conceived, Ito says, ¡§not as a conventional massive crematorium but as architecture of a spacious roof fl oating above the site like slowly drifting clouds, creating a soft fi eld.¡¨
Structural engineer Mutsuro Sasaki worked out how to build it. Sasaki, who also engineered Ito' s Sendai Mediatheque, uses a computational method of evolving and testing shape design so that you arrive at the most cost efficient structural solution.
The method uses an algorithm which, Sasaki says, involves generating rational structural shapes within a computer by using principles of evolution and self-organisation of living
structures from an engineering standpoint. Ito likens this structural analysis to the growth pattern of plants in which, as in nature, a process of great complexity, comprising several hundred evolutionary cycles, produces the final result.
What all that means in layman's terms is that the architect comes up with the shape, Sasaki number crunches it, tests it through computer modeling and comes up with a better, more beautiful, more elegant, more economic form, and tells the architect how to make it.
The most economic material, in this instance, was reinforced concrete. The challenge was how to make the various curved formwork sections and tapered column shapes with absolute precision. To achieve that Sasaki¡¦s digitised data and computer models were sent off to a formwork specialist who produced each section.
We designed with consideration for the relationship with the surrounding landscape, Ito says. We determined the degree of various bumps on the roof according to the ceiling
height required in each interior space of the building. Then we made an initial digital model with which we did a series of structural analysis tests to fi nd the form that achieves the best structural solution.
The form of the roof was determined precisely, using 3,700 check points on a grid. It was constructed by continually cross checking the position of all points, one by one, with
laser level fi nders, to ensure a consistent depth of 200mm for the concrete, with a tolerance of only 10mm. The process was crucial for both the design and the structure.
The roof was completed in five separate pours, using a quick-setting mixture to eliminate the possibility of the concrete sliding off the curving sections. Once hardened, all joint marks were removed with grinding machines and the entire surface trowelled with mortar to create a single surface. A flexible water proofing urethane layer was added later to compensate for any slight movement in the concrete surface.
The result is an architecture of remarkable lightness, of uplifting fluidity. It is timeless and contemplative all at the same time. But the starring role belongs to the roof, all
2,270 square metres of it, which fl oats overhead in peaks and troughs, as a single sheet of billowing almost impossibly thin reinforced white concrete.
The roof's form is a fine balance of functional, servicing, structural and aesthetic requirements. Freely dispersed columns V as slender and graceful as those of Eero Saarinen's legendary tulip table and chairs - drop seamlessly from the undulating ceiling which rises as high as 11.5 metres in parts.
The columns conceal storm water drains and appear to have been cast as one with the roof. The roof canopy extends to protect a screen of 19mm glass encasing the entire building.
The interior plan is organized around a regular arrangement of rectilinear functional and ceremonial rooms placed between the columns as windowless, top-lit boxes of travertine stone.
Beyond the entrance, visitors access two areas where mourners pay their last respects. A corridor leads to waiting rooms and a hall before entering the cremation zone. Detailing is subtle and there¡¦s a clean formal relationship between all parts of the building.
真的好棒喔！一點都不像火葬場！
