Comment by astrodust

Maybe he can. The construction industry has explored a lot of options, but let me tell you something: If there's one group of people that are necessarily conservative about these things it's civil engineers.

A rocket can go to the moon and come back safely, that takes an abundance of caution and significant attention to detail, but it's a fixed-length trip. Civil infrastructure has to exist for decades, or in the case of many American undertakings, well over a century. That requires extreme caution.

If you invented a concrete alternative today it'd take at least twenty years for it to be considered a viable alternative to concrete because long-term studies of the mechanical characteristics of it under a wide variety of conditions will have to be taken out.

Concrete is an extremely complicated material, I know people that have gotten a Ph.D. in aspects of it, and it's very well understood. This hypothetical alternative you're talking about has a lot to measure up to.