DESIGN LIFE

Take a look at the Colosseum in Rome. It was made of concrete and has hung around for a few years.

The outer wall is estimated to have required over 100,000 cubic meters (131,000 cu yd) of travertine stone which were set without mortar held together by 300 tons of iron clamps.[10 (quote from Wikipedia).

Travertine is a porous, sedimentary rock. It is not concrete.

The expected life of a concrete structure depends on a lot of variables. Fifty years is about the norm, although some become victims of corrosive attach and last only twenty or thirty years. Important structures, such as major bridges may have an expected life up to 150 years or more, but constant maintenance is necessary to achieve those results.

Here is one reference. You can find others by Googling "expected life of concrete structures".

"Please provide Reference."

You go first. What are your qualifications? Are you competent to ask these questions?

Are you building a patio, or a 10 story office complex?

Try to use Google or Wikkipedia before you ask us to do your work.

I'll make it easy for you: Google : what is the accepted design life of concrete structures

Lynlynch