Every building, and every person, has at least one if not many "Achilles' Heel". I once read a report by a young engineer that assessed the structural condition of the exterior walls and balconies of an apartment building. I read the report a few months after it was written because I was asked to double check the evaluation and assessment after large chunks of the exterior fell to the ground after reading a report that siginificantly underestimated the severity of the structural balcony slabs.
I noticed that the report never identified the structural system of the building or balconies. Had the system been properly identified, they may have recognized this structural system's Achilles heel and then recognized that the building had bigger problems than they realized. The balconies were ultimately completely demolished and replaced, which is a very rare repair for most balconies, but necessary for these.
My site has two prevailing themes, which are similar... The first is "Buildings are like people, and you have to get to know them." The second is, "Buildings matter because people matter".
This story comes to mind today as I am thinking about two similar Achilles heels. The first is a similar apartment community with similar construction for which I am proposing services. The buildings I speak of were constructed with an antiquated structural system known as "Dox plank", formerly known as "Docs Blocks", named for Bernard A. "Doc" Vander Heyden. The system was a precursor and similar to hollow-core planks, except they were made of cinder blocks that were grouted together rather than of extruded concrete. Both Dox Plank and Hollow Core plank have similar Achilles heels, which is that the deterioration tends to be worse than it appears because the systems are hollow inside, with delicate shells around the reinforcing. The deterioration starts from the inside of the hollow core or cavity.
The second Achilles heel I was thinking of today is excessive eating and drinking, which behaves much like a dox, or hollow core plank, and for which many including myself are vulnerable.
Other structural systems have their own Achilles heels, such as the pour strips and tee-to-tee shear connectors in double-tee parking structures, or unprotected anchors in post-tensioned structures. It is important to understand a building's vulnerabilities or Achilles' heel so they can be more carefully observed, protected and/or repaired.
We all have our problems, but they are more easily repaired with a little due-diligence, curiosity, and research to more accurately get to the heart of the matter.