[smegger001]

Thing is we can use rebar in concrete for indefinately long use if we plan ahead, use sacrificial annodes to stave off corrosion or use stainless steel or use carbonfiber rebar as they won't rust. Hell using a polymer coating on rebar can prevent moisture contacting the surface of steel and rusting but that would require added cost and care when preping to prevent the polymer from being damaged prior to being embedded in concrete.

[Modified3019]

Reinforcing rebar and fibers can also be made out of basalt, which takes care of both corrosion and thermal expansion issues.

[anonymouskimmer]

Are the thermal expansion characteristics the same as for regular steel rebar?