Thu 7 October
The opening session was held at the Sherman Street Event Center, a historic building several blocks from the conference hotel.
The keynote speaker, John A. Ochsendorf, is a a structural engineer who works to preserve historic structures and to reinterpret traditional technologies for contemporary use. He directs a research program in historic masonry structures at the Massachusetts Institute of Technology, where he is an Associate Professor of Civil Engineering and Architecture. Read the transcript of Robyn Williams’ 2006 ABC Radio interview with John.
John’s lecture, entitled Preservation Technology: Perils and Possibilities, was stirring stuff.
He identified a key peril for historic buildings and structures as being structural engineers who were unable to use contemporary design tools (developed for reinforced concrete and steel structures) to justify the structural adequacy of historic masonry structures, leading to the demolition or heavy-handed structural intervention with these structures.
John’s key response was that generally speaking, if a historic building or structure has stood up over an extended period of time, then this was a pretty good starting point for an assumption of safety.
As a materials scientist who has fought his battles in the past with structural engineers who were uncomfortable with the adequacy of structures I was working on, this felt like justification for my battles!
John identified three key reasons for structural engineers to intervene with historic buildings unnecessarily as:
- Fear
- Ignorance
- Money
John illustrated both sides of the equation with excellent examples, and then proposed a pathway for structural engineers:
- Be humble – the builders knew at least as much as we know, and they probably knew more.
- Assume structure is safe, then try to prove it.
- Work in an interdisciplinary team to debate a range of solutions.
John outlined some new analytical methods that have been developed in the past few years that integrate traditional engineering analysis techniques with the power of digital visualisation – I could feel the historic preservation structural engineer sitting next to me twitching with enthusiasm to try some of these out!
John also talked about his work with Guastovino structural tile vaults, and offered to buy lunch for anybody who could identify a building with Guastovino vaults that he didn’t already know about!!
He proposed a generic approach to cracking in historic masonry:
- Usually due to support movements that happened long ago.
- If the cracks are new, monitor them in the first instance.
- Main hazard is due to falling pieces, not the cracking and subsequent potential instability of the structure.
- Avoid heavy stitching of the crack or reinforcement with large amounts of steel.
John also pointed out that there was much further work to do:
- Guidelines for structural engineers working with historic masonry are required
- Better training of structural engineers in working this field is required
- More analysis tools are needed
- Static problems are still being researched; not yet any real work on dynamic problems
I found John’s lecture to be an excellent keynote and starting point for the conference; I was inspired by some of his statements, and I look forward to the opportunity of sharing some of his ideas when I’m next working with structural engineers on historic masonry buildings.
David West
PS John’s new monograph, Guastovino Vaulting: The Art of Structural Tile, is in the bookshops, and is a fantastic volume. On my shopping list now!

