Fire Damage Building - Inspection

[FlemingDoor]

I have been requested to inspect a fire damage brick building in my community. The building is a two story fire station with approx. 3,000 – 3,500 Sq. feet per floor built in the 1950’s. The first floor is approximately 16 feet high and the second floor is 12 feet. First, some of the facts surrounding the building fire and its results. The fire started on the first floor as consequence of an electrical short in one of the fire truck. The second floor collapse and the roof sustain damage. I’m concern with the physical condition of the bricks. I’m a PE and member of AISC and generally deal with issues relating to steel frame structures. Generally, I have little experience with masonry issues. Any suggests and comments regarding my up coming inspection.

 

[csd72]

You need to do some reading, look up the brick masonry tek notes to see if there is something on this.

That said, I would be concerned about two main things in this building.

1. Firstly since you mentioned that the floor has collapsed, I would be concerned about the slenderness oif the external walls (which have effectively doubled in effective height) check this to code, and if it is not sufficient then you need to specify some shoring/tie backs.
If the lower walls are very thick, dont assume they are solid masonry as they may be rubble filled. Check the out of straightness of the walls also.

2. The integrity of the individual bricks, look for cracks or obvious signs of deterioration. I would suggest that you get some of the worst looking ones tested to confirm capacity (remove these after they are shored). Also test the mortar.

The most economical shoring solution for this type of thisng is usually the type that forms part of the final structure. This needs some thought but is well worth the cost savings.

You need to think a lot about health and safety also and how best to achieve your goals without endangering workers.

Good luck.

 

[JKW05]

This may be helpful:

https://www.asce.org/bookstore/book.cfm?book=3979

 

[Soldierson]

Usually fire damaged brick will show obvious signs of heat stress. Heat stresses cause spalling, not necessarily cracking. This should be readily apparent. Ditto for concrete and mortar. But testing is in order if you have obvious fire damage. and temporary shoring is definately in order if these are thin masonry walls due to the increased effective unbraced height when the seond floor collapsed.

 

[Soldierson]

I might add that a simple sounding survey, using a light hammer to tap the brick or concrete, is very usefull in discovering hidden spalls that have not completely popped. Listen for an obvious hollow sound. Hope this helps.