Common rebar is made of unfinished tempered steel, making it susceptible to rusting. Normally the concrete cover is able to provide a pH value higher than 12 avoiding the corrosion reaction. Too little concrete cover can compromise this guard through carbonation from the surface, and salt penetration.
Quick Answer. Maglev trains can reach speeds of up to 361 mph. This was the fastest speed reached by the MLX01, which was measured on December 2, 2003. Executed on the Yamanashi maglev test line in Japan, the test run was administered by the Central Japan Railway Company and the Railway Technical Research Institute. Keep Learning.
The maglev trains are even faster than Japan's famous bullet trains, which currently travel at about 320km/h (200mph). They use magnetic levitation, hence the name, to float above the train tracks. This minimises the friction encountered by ordinary trains, and allows them to travel faster.