Pyramidal bamboo truss structure composed of nodes obtained by additive manufacturing and biobased adhesive.
Spatial trusses, Mechanical properties, Sustainability and Addictive Manufacturing.
The primary objective of this work — to develop and characterise pyramidal truss structures
using bamboo struts and 3D-printed nodes — was fully achieved, successfully balancing
sustainability, low weight, and adequate mechanical performance for engineering applications.
The study validated the potential of bamboo as a structural element, which demonstrated high
tensile strength (≈126 MPa), ductile behaviour (≈2.55% strain), and competitive compressive
properties. The feasibility of the bamboo-to-node interface using PLA was established, with the
castor oil resin adhesive proving satisfactory and crucial for structural integrity, achieving an
average pull-out force of ≈115 N. The comparative analysis between the structures with short
struts (P30) and long struts (P40) revealed a clear trade-off between mechanical and physical
properties. The P30 structures consistently showed the best overall mechanical performance,
with higher strength and toughness (≈7 kJ/m3 ) in the unit cells, and the TR-P30 beams
sustained the highest maximum flexural load (≈122 N). Conversely, the P40 structures excelled
in mass optimisation, achieving the lowest equivalent density (0.045 g/cm3 in the beam),
representing a mass reduction of approximately 43%, in addition to exhibiting more stable post-
peak behaviour. In summary, the work validates the concept of hybrid bamboo/additive
manufacturing trusses, highlighted by their ability to combine low weight with competitive
mechanical performance. The results demonstrate that this architecture is a promising
alternative for light and sustainable engineering, with potential applications in sandwich panels
and space frames.