I think the region the structure is located and the quality of the architects involved will determine how much of the design time is devoted to the way the building destroys itself.

In California and anywhere in the world you have fault zones, architects and engineers are required to take into account how the structure would react if destroyed. Over the decades many "earthquake proof structures" have proven such a claim was comparable to the Titanic's claim of being "unsinkable". As a result considerable developments have been made in fortifying structures and also making sure that in a worst case scenario they come down as safely as possible (imploding).

During the 1906 San Francisco earthquake the brick buildings collapsed into the streets and the falling rubble subsequent fires killed far more than the initial earthquake itself. Rebuilding was then done with earthquake damage in mind.

Skyscrapers, especially in CA, are all designed to implode and any architect worth his/her salt will know what will happen to their baby when the "big one" (a phrase folks in CA are perenially prepared to encounter) hits.

Most demolition teams that destroy old buildings will tell you that there job is pretty easy - that placing a series of sequential, well placed detonators in a few key focal points can bring down most structures into an implosion.

I also recall reading an article with the designer of the WTC, shortly afte 9-11 who said indeed it WAS designed to implode and that the structures folded and gave away exactly as they were designed to.

After the seventies movie "Inferno" about skyscraper blazes, there were also new laws implemented in most states about skyscrapers and fire hazards. Fire escapes, sprinklers and safety had a sudden surge - but also what would occur to the building as it burned was also installed into the minds of the architects.

The WTC had key joint metal supports embedded in the frame which were designed to melt slowly in an inferno and then give away under the weight of the structure itself - and create an implosion.

Besides in today's age the insurance companies don't want to have to pay out to ten or twenty times as many victims and property damage claims...from buildings that tip over - and since insurance goes into the equation as skyscrapers and most large buildings are built - it would be hard to find an older large structure that has escaped this review process as their policy expires and changes carriers or is renewed.

Hoping we don't have to witness other structures results,

SDAI-Tech1