Precast Concrete – History
The History of Precast Concrete Forms and its Innovations The history of precast concrete can be traced back as far as the Ancient Roman Era in which the Romans, looking for ways to strengthen their infrastructure throughout the empire, came across concrete as a suitable material to carry out their architecture design plans. Soon thereafter, they began developing forms allowing them to shape the concrete into many sizes and use them throughout their building process. Many of the ancient Roman infrastructures such as their aqueducts, culverts and tunnels were built on the back of this precast innovation. Although not referred to as “precast” by Caesar and his legions, this was the first recorded record of this type of structural design.
Initially accredited with the official precast concrete design in 1905, Liverpool, England city engineer, John Alexander Brodie, was the first to develop and perfect the idea of using precast concrete forms in modern architectural design. Oddly enough, although the use of precast forms took off at an unbelievable pace throughout Eastern Europe, its uses in British architecture never really gained any traction.
As precast concrete moved forward in its evolution, the innovation of pre-stressing these concrete forms came about allowing for much stronger, more durable forms. What pre-stressing does is lays the concrete in the form over stressed cables and allowed to set up. These cables are stressed by stretching them extremely tightly. Once the concrete is hardened and cured, the cables are then cut allowing them to pull back to somewhat of their initial shape. Because the concrete is hardened around them though, this retraction is minimal. Minimal as it may be though it does retract enough to pull the concrete together even more so that is what provides the form its strength and durability.
In addition to strength and durability pre-stressing concrete provides, it is also watertight and due to its structural integrity can hold up to extremely heavy workloads without issue. These pre-stressed forms are also considered crack-free so they not only will remain water tight, but will also maintain their overall aesthetic design under any conditions.
Another innovation seen throughout the precast concrete industry over time is the use of what is known as hollowcore products. This design uses far less concrete to make up the final product, and actually, in line with its name, is hollow in the center. Hollowcore is an improvement on the previously mentioned pre-stressed precast in that is still uses the pre-stressed philosophy for strength, however tubes, generally measuring between two-thirds to three fourths inches, are also run through the middle of the forms and then removed once the forms have cured. This provides the hollowcore forms the strength and structural integrity provided by pre-stressed forms, while also making them much lighter in the process. In addition, whereas precast concrete as a whole is a very green product already, having to use much less material in its creation, makes hollowcore products among the greenest within the precast industry.
The last innovation realized within the history of precast is the used to multiple aggregates in effort to provide innovative and cutting edge designs in how the exteriors and in some cases, interiors of a building appear. Although still structurally sound in their design, many businesses are using varying design levels of precast concrete forms for their buildings signs, storefronts, or architectural structures within their buildings.