One startup’s paper-thin stainless steel could change how bridges are built

The article discusses a startup, Allium, that has developed a novel stainless steel-clad rebar designed to significantly improve the durability of concrete bridges by preventing corrosion. Traditional steel rebar embedded in concrete is prone to rust, especially in bridges exposed to water and salt, leading to premature structural failure. While stainless steel rebar resists corrosion, its high cost limits its use to only the most critical bridges. Allium’s innovation involves covering conventional rebar with a thin layer (about 0.2 mm) of stainless steel, which can extend a bridge’s lifespan from 30 to 100 years. This approach aims to offer corrosion resistance comparable to full stainless steel rebar but at a cost similar to or potentially lower than epoxy-coated rebar, the current mid-tier solution. Allium’s stainless-clad rebar has already been used in several bridge deck replacements in the U.S., including projects in Massachusetts, California, and Florida. Unlike epoxy-coated rebar, which requires careful handling,