Bamboo Stage Design

Abstract

The event industry's reliance on carbon-intensive materials necessitates the exploration of biobased alternatives. While bamboo possesses an excellent strength-to-weight ratio, its biological variance, high susceptibility to longitudinal splitting, and the lack of standardized, non-destructive joinery severely restrict its use in rapidly deployable festival environments. This research investigates how to develop a modular, easily demountable bamboo construction system that meets the rigorous safety, logistical, and architectural requirements of temporary event stage designs.

Employing a research-through-design methodology, the study synthesized theoretical mechanics, regulatory safety standards, and empirical insights from industry professionals. Through an iterative process of Multi-Criteria Analysis (MCA), 1:1 physical prototyping, mechanical strength testing, and (digital) structural simulations, a braced framework topology was developed. The finalized system operates on an expanded 1.0m, 1.5m, and 2.0m modular grid, utilizing bundled quadruple-culm vertical columns to ensure structural redundancy and geometric symmetry.

To accommodate natural material irregularities without inducing stress concentrations, a non-destructive, discrete radial friction-clamp joint was engineered. Physical pull-out tests indicated a maximum tensile capacity of approximately 2 kN per joint at an 8 Nm clamping torque. Because this capacity is insufficient to independently resist critical wind-induced tensile loads, an active global pre-tensioning strategy using diagonal straps was implemented. 2D structural simulations verified that applying a 4.0 kN prestress successfully neutralizes tensile forces, allowing the bamboo culms to safely transfer loads via pure end-bearing compression against the steel nodes.

While the physical assembly of a 1:1 scale PA-tower prototype successfully demonstrated the system's logistical feasibility and low-tool assembly potential, critical limitations remain. The current structural validation relies entirely on 2D simulations, necessitating comprehensive 3D analysis under complex stage geometries and dynamic load cases. Furthermore, the proposed “acoustic tuning” method for accurately pretensioning the diagonal straps on-site remains unverified, and the 1:4 load-capacity ratio between the single horizontal members and bundled vertical columns proved somewhat inefficient for large spanning structures. Overall, the modular bamboo system serves as a highly promising proof-of-concept for circular festival infrastructure, but requires further optimization before full-scale commercial deployment can be realized.