Digital Design and Fabrication of Timber Plate Structures | University of Queensland
Jun. Prof. Christopher Robeller( Digital Timber Construction DTC, TU Kaiserslautern), Dr. Joe Gattas (Senior Lecturer, University of Queensland), Kim Baber (Fellow, University of Queensland).
“Traditional wood joinery techniques were successfully employed for hundreds of years in the construction of tall timber structures. Thanks to a resurgence in mass timber construction and a proliferation of computer-numerically-controlled (CNC) fabrication machinery, these integral joints are again an economical and performative way to construct timber buildings”. — Jun. Prof. Christopher Robeller
Intro
The day started with registration, coffee and a general get-to-know-you. Approximately 40 students, architects and engineers from UQ, QUT, Melbourne University, and the University of Sydney were in attendance, with Scott Crichton, Matthew Wash, Ivan Navajas, Ninotschka Titchkosky and myself joining from BVN.
Hosted by the University of Queensland’s Centre of Future Timber Structures Lab and organised by Dr. Joe Gattas and Kim Baber, the workshop featured a series of lectures and practical tutorials by guest Jun. Prof. Christoper Robeller of TU Kaiserslautern; a renowned Swiss academic and architect whose research in innovative timber structures, design for assembly and digital fabrication has been widely published in scientific journals, books, conferences and exhibitions.
For reference, The Future Timber Hub, funded by the Australian Research Council, is one of Australia’s leading timber research collaborations bringing together experts from industry, government, and academia who are committed to the future development of tall timber buildings in the Pacific region. The Hub is an interdisciplinary partnership between the University of Queensland, the Queensland State Government Department of Agriculture and Fisheries, Arup, Hyne Timber, Lendlease, the Queensland Fire and Emergency Services (QFES), Scion NZ, Griffith University, the University of British Columbia and the University of Canterbury.
Session 1 — Background
The workshop kicked off with Christopher’s first lecture. We explored some basic structural definitions and a brief history lesson of the application of folded-plate structures in the built environment.
“The structural efficiency and benefit of a folded-plate is due to the rigid combination of several oblique surfaces along their edges, the elements functioning simultaneously as a plate, slab and frame. The resulting stiffness makes it possible to span larger distances without intermediate support”. — Jun. Prof. Christopher Robeller
We learned that, perhaps counter-intuitively, many of the earliest folded-plate type structures were realised in hand-laid masonry and concrete. In particular, the work of Uruguayan arhitect and engineer Eladio Dieste was discussed; his structural solutions, which included free-standing vaults, gaussian or double-curved vaults, ruled surfaces, and folded planes, were all based on the rigorous understanding and masterful use of reinforced ceramics.
Excellent link below;
Bringing the discussion back to timber, Christopher revealed that it was only with the invention of CLT (cross-laminated timber) and LVL (laminated-veneer lumber) in the 1980’s did such folded plate structures became possible with commercially available timber products.
Further, in addition to being highly sustainable and recyclable, timber folded plate structures exhibit an excellent strength-to-weight ratio, and with the development of modern CNC processing and recently published algorithmic techniques, a fully-digital workflow has become possible for such structures.
Session 2 — Algorithmic Processing
The integral form-fitting joint is one of the oldest known, and most commonly applied methodologies for the assembly of building components. It was only with the industrial revolution however, that mass-produced mechanical fasteners became preferable, even despite their often poorer jointing performance.
Christopher claims however that in the context of today’s built environment, where prefabrication and rapid assembly of bespoke building elements has become crucial, the benefits of digitally generated form-fitting jointing is becoming increasingly apparent. To demonstrate his point, he took us through two of his most recent and ambitious projects; the Vidy Theatre Lausanne, and the Multipurpose Hall Manternach.
Vidy Theatre, Lausanne
The Vidy Theatre Pavilion is a 250 seat, 540m² auditorium in Lausanne, Switzerland built for the Théâtre Vidy-Lausanne. Designed in joint venture by Architect Yves Weinand and l’Atelier Cube SA, and developed in collaboration with the Laboratory for Timber Constructions, IBOIS, EPFL, the $3.86M AUD de-constructable pavilion was the product of recent research by Christopher and Yves on active structures made from structural wood panels and the development of wood-wood connections between these panels.
The pavilions structural system is an unprecedented double-ply load-bearing structure made from beech plywood panels with innovative double-through tenon jointing integrated into the panels. A total of 500 individually shaped plate elements create the doubly-curved, folded shape that allows it to span 20 meters with a plate thickness of only 45 millimeters.
Multipurpose Hall, Manternach
The Manternach Multipurpose Hall Project consists in a series of 23 vaults with spans ranging from 22.5m to 53.7m and a constant height and width of 9 and 6m respectively. The project will accommodate a 5800m² facility including a timber prefabrication factory space and offices.
Each arch is a double-curved shell structure with a design inspired by Eladio Dieste’s Gaussian masonry vaults. The shell is made of two interconnected layers of timber plates assembled with through-tenon joints. The vaults present overlapping s-shaped cross-sections. The plates are interconnected using 1DOF (one rotational degree of freedom) integral joints between all the plates (vertical and horizontal).
Session 3 —Timber Plate Structure Plugin
Over the course of many years of research and prototyping, Christopher explained that he had continuously refined the digital methodology by which he would simulate, analyse, fabricate and assemble both his prototypes and full scale structures.
“With a coded, parametric workflow, we were able to change the geometry of the joint connections for the Vidy Theatre one week before the production of the plates began (for 3000 connections). You could not or would not do this in a traditional, manually documented workflow.” — Jun. Prof. Christopher Robeller
After a short computational geometry refresher on NURBS, meshes, surface planarity and data structures, Christopher proceeded to introduce us to his Timber Plate Structures Plugin (TPS) for Grasshopper (a visual scripting environment for Rhino); the software he has used to design, develop, analyse, and fabricate much of his built work.
In addition to being given (read: gifted) Christopher’s TPS plugin as part of attending the course, we were given many example scripts illustrating it’s various functionalities. I have described and screen-captured a number of these below;
- Diamond Mesh (Yoshimura Fold) Mesh Generator — Turns an input NURBS surface into a Diamond Mesh with U number of horizontal divisions, and V number of vertical divisions.
- MTS Joint Generator — Takes an input ‘folded’ mesh geometry, and creates 3D plates connected by dovetail, finger joints, or miter joints.
- TPS Loftcut Simulator — Takes an input set of cutting curves (two polylines representing the upper and lower plate surface boundary), and creates the standardised G-Code (the language standard for modern CNC machines) required to fabricate the geometry.
In addition to these examples, we were given scripts and workflows achieving reverse-folding meshes, mesh analysis, miter jointing, machine simulation, and even KUKA-prc compatibility.
It is no stretch to say that in the sharing of his software, Christopher is enabling a significant number of academics, professionals and even enthusiast’s to practically apply, critically review, and publicly discuss the benefits and possibilities of applying integrating jointing methodologies and digital fabrication techniques in architecture, engineering and construction.
Session 4— Tour
The day ended with great talks from Dr. Joe Gattas and Kim Baber about their research at UQ, a tour of the University of Queensland’s Future Timber Hub and Advanced Engineering Building, and networking drinks in the late afternoon.
There were significantly more details, insights and files shared throughout the day with regard to Christopher’s work in software, construction and research, and Joe and Kim’s research and work at UQ. Should anyone reading this have any further questions about specific part of his talk, or even copies of my detailed notes, please comment below.
Scott Crichton, Matt Wash, Ivan Navajas, Ninotschka Titchkosky and myself were supported to attend the Digital Design and Fabrication of Timber Plate Structures Workshop by BVN Architecture.
