Investigation

Relating Damage To Structural Type

by Don Friedman on November 22, 2017

Some stereoscopic views of Chicago after the 1871 fire:





That’s the kind of devastation that a firestorm can cause. But it’s worth noting that different types of building fail differently. Nearly every building in Chicago before the fire was either of wood-stud construction (private houses and small commercial buildings) or of masonry walls with wood joists (larger commercial buildings and public buildings). The three buildings pictured above had masonry walls or there’d be nothing to show; as it is, we’re looking at wall remnants and nothing else.

This pattern of failure in a fire is specific to masonry-bearing-wall buildings with wood interiors. Even a building with an unfireproofed steel frame, which would fail as completely in a fire, would fail in a different pattern: because such a building would have thinner walls, it would not leave masonry standing.

If you read enough descriptions of old fires, the pattern repeats itself of the interiors burning out and the walls standing for a while and then either collapsing or being torn down for safety. Just as the introduction of new technology changed the way buildings were constructed and therefore changed the way they were perceived during construction, it changed the way buildings fail and how their failures are perceived. The buildings above are obviously a complete loss, and making the masonry walls thicker and stronger would not have prevented their destruction. The introduction of “fireproof” construction, starting shortly after the Chicago fire, meant that the type of failure in the pictures above became less common over time.

An Alarming Symptom, Maybe

October 23, 2017

Sometimes issues during an investigation aren’t clear. That picture is the entry to an abandoned church and that’s a really odd crack in the floor. I was there to do the most basic type of conditions assessment – hazard to the public or not? – and since the building was closed to use, the only […]

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Patterns of Damage

September 28, 2017

João Carlos Souza has a primer up on ArchiNet on how to identify problems in concrete buildings based on crack patterns. Putting aside some bad translation from Portuguese to English* it’s quite good and can help identify damage when used as intended. Mr. Souza does not explicitly state the assumptions that went into his visual […]

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Historic and Modern Structural and Non-Structural Detail

September 11, 2017

I hope the title is broad enough…I wouldn’t want to leave anything out. This is a probe in the facade of the penthouse of a 1920s apartment house. The exterior of the masonry facade has been stuccoed, which is why the background is so white. The pipe in the lower right corner is part of […]

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Anna Karenina in Concrete

September 10, 2017

Tolstoy said that “Happy families are all alike; every unhappy family is unhappy in its own way.” This principle can be applied to buildings: every building in good condition is alike, every failing building fails in its own way. The white paint on the concrete does a great job, in my opinion, of highlighting where the […]

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Snapshots

August 30, 2017

The front entrance of Castle Clinton in 1896: The front entrance of Castle Clinton in the 1970s: We’ve been writing a lot of conditions reports lately. Just coincidence, really: as a small firm, the type of work we have at any given moment can vary. Some months are more design intensive, some more construction intensive, […]

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An Added Benefit

August 27, 2017

We climb scaffold for a single purpose: to see some aspect of a building up close in order to better understand it. But a lot of the time (click on the panorama above to enlarge it) the view is worthwhile in itself.

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Is a Non-Dead Building Ghost a Building Zombie?

August 24, 2017

Another old picture, but this one is not quite a ghost. The curved mansard roof (that is visible as a curved pattern on the side wall) was part of the extent building before its unfortunate extension. The extension added one full story and made the mansard level the same size as the typical floors below, […]

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Building Ghosts From 15 Years Ago

August 23, 2017

I’ve been digitizing old rolls of film* and I came across a bunch of pictures I took, between 15 and 20 years ago, of building ghosts. Most of these ghosts are no longer visible: the current building boom in the city has resulted in the disappearance of a lot of vacant lots and parking lots, […]

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Beautiful Brickwork Marred

July 25, 2017

Friend of OSE – and occasional collaborator – Glenn Boornazian sent me a few vacation photos from Massachusetts. That’s pretty nice masonry for an apparently abandoned building. In a non-aesthetic sense, the interesting stuff is going on near the eaves. That’s a damned big crack and displacement at the corner pier. The crack starts at […]

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