PracticeForm · analysis · detail
From knowledge of the material to the calculation of each connection.
Designing in bamboo means working with a natural material, with a hollow section and properties that vary from culm to culm. Our practice brings together three mutually reinforcing strands: knowledge of the material, parametric models that find the form, and structural analysis that checks every element. The studies below all start from the same longitudinal bamboo roof.
01MaterialSpecialised bamboo design
Specialised design starts with the material.
Each culm is unique: the design must know how to read the material before drawing it.
Bamboo is light, strong and fast-growing, but it behaves neither like sawn timber nor like steel. Its culms are hollow, have nodes and walls of variable thickness, and the longitudinal fibers that give it tensile and bending strength also make it sensitive to crushing and splitting when it is cut, drilled or supported in the wrong direction.
That is why design develops together with technique: the choice of species and diameter, treatment and drying, protection from water and sun, the way culms are grouped into bundles and the path of each force to the ground. In a well-resolved structure, the elements work mainly in compression and tension along the fibers, and the connections sit where the culm can take them.
02FormParametric tools
Parametric tools and form-finding by physical simulation.
Changing one parameter updates the whole system: this is how the structure comes to be understood as a whole.
Before computers, Antoni Gaudí was already finding form with physical models: hanging chains and weights that, inverted, revealed arches and vaults working in pure compression. Decades later, Frei Otto investigated soap films, nets and hanging models to arrive at lightweight roofs and gridshells such as the Mannheim Multihalle (1975).
Today the same principle lives in parametric mathematical models. In Grasshopper, geometry is no longer a fixed drawing but is described by rules and parameters: spans, heights, curvatures, sections. Each parameter is linked to the others, so the model serves both to find the form and to test it and compare alternatives.
Physics as a design instrument.
Kangaroo solves a system of particles and forces until equilibrium. On the roof, the mesh of 4,106 nodes is fixed at the eave and receives upward pressure, greater at the center (1.16 kN/m²) than at the ends (0.69 kN/m²). The surface that emerges is not drawn by hand: it is the form in equilibrium with the load, the same idea as the physical models of Gaudí and Frei Otto.
Calculation within the model.
Karamba3D turns the geometry into a member model: each culm becomes an element with its real section, and self-weight, roofing and wind are applied right there. Because the calculation lives inside the parametric model, every change of form instantly returns displacements, internal forces and the ISO 22156 check.
Compare to choose.
Galapagos is an evolutionary solver: it generates variations, measures each one against a criterion, the fitness, and keeps the best. In the search for slenderness we followed this logic with seven versions of the structure, each one calculated and compared by bamboo mass among those that meet the code.
deformed shape magnified 60 times
03StructureStructural analysis and design
Structural analysis, wind simulation and connection design.
Confidence in the structure comes from codes, testing and research.
Structural design in bamboo rests on a technical foundation that has matured over recent decades: ISO 22156, the international standard for the design of bamboo culm structures; ISO 22157, which defines the tests for physical and mechanical properties; and a growing body of academic research and construction manuals. It is this knowledge that turns a traditional material into a reliable structural system.
In the finite element model, each culm is a member with its real section. The results show how the structure deforms, where it works in compression or tension and where the elements bend; reading the utilization shows, element by element, where the system still needs adjustment.
Fig. 05 — Utilization of each bundle under ISO 22156, the highest of the eight wind directions.
Light and slender, a bamboo roof finds in wind one of its most sensitive actions.
Suction, force reversal and uplift at the bases matter as much as self-weight. That is why we simulate the flow in CFD from local wind data and bring the pressures into the structural model, checked in all eight directions. Seeing the air pass through the roof helps decide curvature, mesh spacing and the position of supports.
Fig. 07 — Karamba3D member model, one culm per member: deformation under self-weight, deformation under wind, axial force and bending moment.
The connection translates the logic of the structure into a building element.
The detail closes the cycle. Each connection is designed from the forces at its joint, respecting what the culm allows in holes, cuts and bearings: fish-mouth cuts with threaded rods at the joints, through-bolts at the crossings, straps on the bundles and steel bases that keep the bamboo away from water and carry the reactions to the concrete block.
Fig. 08 — Connection and foundation details of the Trancoso Restaurant (bamboo structure, V3.3), developed from the forces in the model.