Steam curing is a widely used accelerated curing method for precast concrete tunnel segments (also known as segmental tunnel linings or precast tunnel lining segments). These large, curved, high-precision concrete elements form the permanent structural lining in mechanized tunnel boring machine (TBM) projects, such as metro systems, highways, rail tunnels, and utility corridors.

In precast production plants, steam curing accelerates cement hydration by applying controlled heat and high humidity, enabling rapid early-age strength gain. This allows segments to reach sufficient compressive strength for demolding.