Architectural precast concrete is generally defined as any precast product that contributes to the aesthetic and architectural value of the structure. Products include buildings, wall or panel systems, sound barriers, picnic tables, ornamental pieces, signs, support slabs, columns, etc.
Many suspect the precast concrete industry began in ancient Rome, as the extensive network of underground tunnels that exist to this day seem to indicate the use of precast building materials.
However, the documented history of the modern-day precast concrete industry began in the 1900s when an English engineer by the name of John Alexander Brodie discovered precast concrete components could come together to build a structure efficiently. Brodie was first to get a patent for the process of creating precast concrete paneled buildings.
In 1950, the first major precast concrete structure appeared in the United States — the Walnut Lane Memorial Bridge in Philadelphia. This bridge is recognized by many as the beginning of the precast concrete industry in the United States as we know it today. A few years later, the Precast Concrete Institute was formed to begin to set standards for this emerging industry.
PRECAST CONCRETE MANUFACTURING
Precast concrete is created off-site using a mold. That’s the main difference between precast concrete and site cast concrete, which is poured into its final destination on site. Here is a simplified overview of the precast concrete process:
Precast concrete is poured into a wooden or steel mold with wire mesh or rebar. This mold may also have prestressed cable, if needed.
It is cured in a controlled environment — usually at a plant.
Once finished, the precast concrete is transported to a construction site and put into place.
It’s important to note that not all precast concrete is prestressed with cable reinforcement. The addition of this reinforcement is particularly useful in many structures and buildings where maximizing the strength of the concrete is essential. The addition of the wire or rebar provides tension within the concrete, which is released once curing is complete. The release of the wire or rebar tension transfers strength to the concrete, creating an even stronger material.
Regardless of whether or not prestressing is a part of the equation, this process is faster, safer and more affordable than standard concrete. Precast concrete materials help you maximize your project’s potential while making sure it is completed on time. They are also among the most versatile products in construction, combining a strong structure with the ability to:
Choose any combination of color, form or texture
Meet compatibility requirements for historic structures
Create everything from small sections to long open spans
Be recycled or reused upon removal or replacement
TYPICAL PRECAST PROJECTS
Perhaps the versatility is one of the reasons precast concrete structures are so diverse — ranging from parking garages, bridges and office buildings to stadiums, retail shops and housing. It’s clear any number of building types can benefit from the advantages of precast concrete products. Some of the most common construction projects that use precast concrete are listed below.
PRECAST CONCRETE STRUCTURES.
Since durability is one of the key characteristics of concrete construction, it’s no surprise that many precast concrete structures are used in applications that see a lot of wear and tear from everything from traffic to weather elements. Going hand-in-hand with durability is its strength — another reason it is especially popular for these applications.