Conventional cast-in-place concrete and shotcrete share many of the same properties but shotcrete provides an advantage in placement. It bonds with most substrates instantly or very rapidly, which makes it a good choice on complex forms or shapes. Similarities to conventional concrete include high strength, low permeability and high durability. It has a wide range of applications that include repair or restoration, ground support, architectural and landscape restoration, new construction and much more.
Shotcrete, originally known as gunite, was developed by Dr. Carl E. Akely. In his process, the dry material was blown out of a hose and water injected at the nozzle. Akeley went on to patent his cement gun and the material he called Gunite. During that period, he created the Cement Gun Company (now called Allentown Equipment).
In the mid-1950s, a wet mix method was introduced to the construction industry. The benefits were recognized immediately and it was used on many projects. Shotcrete became even more popular with the development of a rotary gun that had an open hopper which allowed the material to be continuously fed.
The American Shotcrete Association credits the technical advancements in materials and equipment made in the 1970’s of providing an enormous improvement in the application of shotcrete. They state that, “Perhaps the most significant step in this period was the development of efficient concrete pumps that could be used for wet shotcrete application.”
The 1980’s continued with advancements in the mixing and batching of ready mix concrete and the development of admixtures that allowed for consistency, hydration and performance. Today one of the biggest changes to shotcrete applications is the ability of modern equipment to pump any slump as well as to pump it over long distances and up into high-rise construction projects.
The Conco Companies are leading suppliers of concrete services for the Western United States. We got our start in the Bay Area in 1959 by offering clients the best value on a wide range of concrete services and products. Since that time, we have taken a leading role as one of the top concrete contractors in the region. We have four regional offices serving California, Washington, Oregon, Nevada and Colorado.