https://youtu.be/TnlCRoBAcuw
I am not a structural engineer (or an architect for that matter). But one of the things that has come to greater light as a result of the devastating earthquake that hit Turkey & Syria last month is the number of "soft story buildings" throughout these countries.
Technically, a "soft story building" is exactly what the name suggests. It is a building where one floor is less than 70% as stiff as the floor above it, or less than 80% as stiff as the average of the three floors above it (source).
The typical application of this is a ground floor that has less structure (missing shear walls for example) and is more open. And it is usually done to accommodate things like parking and retail uses, and to, of course, build more cheaply.
However, there is a massive problem in that they are often structurally suboptimal! (Again, not a structural engineer.) This is why we saw so many of the buildings in Turkey "pancake" during its earthquake. The ground floor failed and then it brought down the rest of the building.
I can appreciate that retrofitting older buildings is both difficult and expensive; but it is inexcusable to not work toward that and it is certainly inexcusable to not mandate that every new building meet whatever building codes are required to save lives.
