TOPCOR Shotcrete Restorations Services:

Repair and Restoration of concrete structures is one of TOPCOR Services fastest growing market segments. Our customer base has come to rely on the quick, effective method of pneumatically applied concrete known worldwide as Shotcrete . Shotcrete can be applied using a wet or dry process, and is used for new construction as well as repairs.

Shotcrete has often been described not as a material but as a process. Both wet and dry process produce a material that exhibits superior hardened properties to conventional concrete, such as high strength, low permeability and high durability. These properties allow Shotcrete to be used as a structural rebuild material.

Shotcrete and gunite are two commonly used terms for sprayed concrete. Shotcrete is mortar or concrete conveyed through a hose and pneumatically projected at high velocity onto a surface. Shotcrete undergoes placement and compaction at the same time due to the force with which it is projected from the nozzle. It can be impacted onto any type or shape of surface, including vertical and overhead areas.

Shotcrete is today an all-inclusive term that describes spraying concrete or mortar with either a dry or wet process. However, it may also sometimes be used to distinguish from gunite as a wet mix. Shotcrete can be applied in either the dry mix process or the wet mix process. Job site logistics, material mix design, configuration of area to be sprayed and production rates are some factors that should be considered when choosing which process is most beneficial to the customers project needs. Both have advantages and disadvantages that may make one or the other more desirable for specific job requirements.

The dry-mix Shotcrete method involves placing the dry ingredients into a hopper and then conveying them pneumatically through a hose to the nozzle. The nozzleman who holds the nozzle then controls the addition of water at the nozzle. The water and dry mixture is not completely mixed, but is completed as the mixture impinges on the receiving surface. This requires a highly skilled nozzleman, especially in the case of thick or heavily reinforced sections.

The wet-mix Shotcrete method involves pumping of a previously prepared concrete, typically ready-mixed concrete, to the nozzle. Compressed air is introduced at the nozzle to propel the mixture onto the receiving surface. The wet-gun procedure generally produces less rebound, waste (when material falls to floor), and dusts compared to the dry process procedure.

As in regular concrete, Shotcrete also uses admixture technologies to custom blend a mix design to meet the customer's specific needs. (Silica fume, fibers, refractory blends, accelerators or retarders to name a few.) The versatility of the proven process of Shotcrete has outstanding support from owners, architects, engineers, and contractors alike.

Common Applications for this technology:

1. Swimming Pool construction
2. Retaining walls
3. Refractory Installation
4. Rockscaping
5. Slope Stabilization
6. Concrete Repair / Rehabilitation of concrete and Masonry structures (bridges, walls, columns, beams, slab soffit areas, sewer infrastructure)
7. Civil and Infrastructure projects
8. Mining operations
9. Highway and railroad tunnels
10. Canal lining
11. Slope stabilization
12. Pipe lining
13. Seismic and blast proof retrofitting