The Hyperbolic Paraboloid Research Pavilion, made with bamboo, is an attempt to explore the geometric potential of hyperbolic paraboloid curved surfaces in creating architectural spaces. The design process began with the question of how a complex geometry could be produced accessibly through a bottom-up approach and how it could be utilized to generate space. Bamboo was selected for its structural and environmental benefits. The hyperbolic paraboloid presents a geometric form that, despite the complexity of its surface, can be produced using linear elements. Additionally, its modularity allows for structural expansion. The design process started by generating and examining various smaller-scale options. The selected module allowed for covering large surface areas without the need for columns in the center of the space. Furthermore, the hexagonal plan provided the potential for modular expansion, one of the other features of this structure. In such a setup, the integration of architecture and structure became a key feature.
Upon further observation of the design, several recommendations were made for utilizing this structure. Its lightweight yet strong frame, ease of assembly, and potential for expansion made it suitable for emergency shelters. The design process moved forward to strengthen the project in these areas. The use of pre-fabricated parts allows for easy on-site assembly. Temporary structures used in crises must have short construction times, sufficient strength, accessible materials, and sustainability.
2. The Importance of the Hyperbolic Paraboloid Structure
Due to the potential of the hyperbolic paraboloid, advancing this research became increasingly important. By examining various structures, the hyperbolic paraboloid was chosen. The hyperbolic paraboloid gains strength from its shape. Its curvature reduces the tendency to buckle under compression, and with bracing in two directions, it experiences no bending and can resist uneven loads, whether from dead loads (such as hanging equipment) or live loads (such as wind).
3. Structure Expansion
Another feature of the structure is the receiving edges of the cells, which allow for expansion. To create a structure capable of expanding, a saddle-shaped curve was formed using straight columns. After aligning the columns side by side, a surface was created, and through the edges, the cells were expanded. Initially, the expansion in one direction was tested, followed by a four-cell arrangement, which failed in all cases due to uncontrolled growth or growth without a specific pattern. The goal was to create a structure that could expand in all directions as needed. Stability was achieved by arranging six modules, creating a unified structure. Throughout the development, experimentation played a key role, and innovative solutions were continuously devised to address challenges.
4. Model and Prototyping
To understand the challenges, a scale model (1:200) was made using wooden skewers. The cell frame was constructed using skewers and varnish, with the spacing pattern also determined by skewers. To create the hyperbolic paraboloid surface, twenty-two skewers were used as secondary beams.
For connection designs, a more detailed study of the forces acting on the structure was needed. Therefore, a larger mock-up was created using reed (a plant), which behaved similarly to bamboo. The articulated frame of each cell was made using reeds, flexible pipes, and gas clamps. The spacing pattern was made with reeds fixed in the ground at specific intervals, and the hyperbolic paraboloid surface was formed with ten secondary beams connected with wooden pins. Based on the structure, the upper receiving edges were attached with zip ties, and the bases were connected to the ground with rigid joints. This structure could be assembled by local labor without specialists and expanded under any conditions.
5. Assembly Process
In this phase, we reached conclusions that influenced the design and construction of bamboo joints, leading to a new construction method for bamboo structures. Bamboo with a diameter of 5 to 7 cm was selected, cut to specific dimensions, and stored vertically in a covered area for drying. Thicker bamboo was separated for beams and columns, while thinner poles were used for secondary beams. After cutting and coding the bamboo poles, they underwent treatment to protect against pests, fire, and moisture, which involved heating the poles to release the bamboo resin.
6. Foundation and Structural Assembly
Due to the outward thrust of the bases and the inward thrust of the main beam, a foundation was used. The base spans were determined, and the foundation was constructed. Finally, plates were installed to connect the articulated base joints to the foundation.
Leftover bamboo poles were used to create 15 cm-long pins. To maintain the articulated frame and support the weight of the bamboo, four-way cross bearings were used for the beam and column connections. The columns and beams were assembled separately with rebar and mortar. The rebar was welded to the two-way bearings in the bamboo poles and fixed with mortar to complete the frame. The secondary beams were marked, drilled, and connected to the main beams using bamboo pins.
7. Jointing the Structure to the Foundation
Upon observing the reed structure, it became apparent that the pressure exerted on the center of the structure called for a central ring to neutralize the pressure and stabilize the modules. A hexagonal shape was used to better fit the bamboo edges into the ring. After the cells were completed, the central hexagon was placed in the middle of the structure, with one hyperboloid attached to it and to the base joint. The remaining hyperboloids were then placed next to each other to form a six-cell arrangement.
8. Conclusion
This project resulted from a detailed study of the materials, geometry, and structure. At every stage, the bottom-up process was repeated, using lessons learned along the way to refine the structure. Due to the construction process, where structural components are pre-fabricated in the factory and assembled on-site, the project execution time is reduced, and the environmental impact of off-site construction is minimized. The project strives for environmental sustainability by using recyclable and eco-friendly materials like bamboo and iron, aiming to minimize the damage caused to nature and reduce pollution from construction and demolition. Geometry played a crucial role in shaping the structure, achieving stability and expandability in the cell arrangement. This structure’s portability, flexibility, and multi-functionality, along with its low-cost assembly and disassembly in various locations, set it apart. As it has learned from past projects, this structure aspires to provide solutions for future architectural endeavors in this field.
