Some examples of companies that sell precast concrete stairs include Shea Concrete Products and Stepstone Incorporated. Other such companies are Wiggin Means Precast Company Incorporated and Leesburg Concrete.
Precast concrete stairs are made in a factory using a mold into which the concrete is poured. The liquid cools into form, the mold is removed, and the product is transported to the construction site to be put in its place. There are numerous benefits to precast concrete in general, some of which include improved safety and quality. These improvements are partially due to greater supervision in a factory environment than is possible in an on-site concrete pouring environment.
Precast concrete technology was first developed by the Ancient Romans to aide in their grand construction of aqueducts and other innovations. The technology was revived in modern fashion in 1905 in Liverpool, England. Today, almost every building in the first world contains precast concrete sandwich wall panels, and some structures, such as homes, owe their entire backbone to precast concrete.
Prestressed concrete is a very common type of precast concrete in large modern structures such as bridges. The concrete is applied to steel cables while they are under tension. When the concrete dries, the tension is transferred to the concrete in the form of static friction. This process allows any additional tension to the bridge to be directly transferred to the cables, which distributes the weight load.