TUESDAY, APRIL 16, 2019
A curved plywood pedestrian bridge, able to support up to five people, recently took shape thanks to researchers and students based out of Centro de Estudios Superiores de Diseño de Monterrey, in Santa Catarina, Mexico. The project, known as Bending Bridges, implements a double curvature design.
Though planning and conceptualizing took a year, actually building the structure only took four weeks. The span is 12 meters (roughly 40 feet) long and has a maximum height of 2.5 meters.
Wooden Pedestrian Bridge
The design for the bridge implements a local active bending principle, focusing on utilizing the plywood’s elastic bending capacity. The structure also fulfills both architectural and structural constraints. Computational structural analysis was used to design both the arch and the surface curvature.
Bending Bridges from ME-ST on Vimeo.
Bending Bridges’ curve allows for the optimal distribution of forces, while minimum bridge inclinations were retained at both the top and bottom of the arch.
“In order to allow the assembly of doubly-curved geometries, discretization of strip patterns were introduced in the design process, generating [a] series of unique curvy-linear unrollable members,” the team writes on its website.
By segmenting the bridge’s assembly, the structure could be built section by section, gradually moving toward the center. The double-layer system was integrated into this process, which allowed each section to be put into place without the material springing back.
To address heat and humidity as part of the treatment of the wood, the team developed a wood steaming method, which included a wooden box, a gas tank, a custom stove, sealed pots, stretchable aluminum pipes and a hygrometer, to enhance the bendability of the material.
Bridge members and connections, both digitally fabricated, were computationally designed with 3D modeling and then created with CNC milling. The spine-like design distributes the load to the foundation, cutting out the need for additional support structures.
Kenryo Takahashi served as the structural consultant on the project. Bending Bridges was part of the Strip Strategies Studio 2018 course.
Tagged categories: Bridges; Infrastructure; Program/Project Management; Research and development; Wood
