Shotcrete is our preferred material in hard-to-reach, difficult-to-form areas. It is comparable to concrete in strength and durability, however has the benefit of not needing form work. It is shot out of a nozzle at a high velocity into the prepared surface, which it adheres to. When finished, it looks the same as concrete.
Our team includes four certified nozzlemen for overhead and vertical applications, including Neil McAskill, who is also a certified examiner with the American Concrete Institute.
TERMINAL DOLPHIN REPAIR
This ocean repair of a docking dolphin was complicated by tides. We used a large barge to bring our concrete repair equipment and shotcrete pump to the site. Shotcrete was used after the old concrete was chipped away and a clean surface was left to work with.
WASTE WATER TREATMENT PLANT
The sewage treatment plant of a major metropolitan city required us to go into each of thirteen pre-aeration holding tanks. The covers installed over these tanks trap H2S gas between the effluent water and the covers. The H2S gas reacts with the exposed concrete, creating sulphuric acid which degrades the cement paste.
The repair work was conducted in a confined space and biohazardous work environment. We implemented a detailed confined space entry work program with full-time air monitoring and active ventilation to ensure the safety of our crew.
We found that hydro demolition with a 20,000 psi hydro unit was the most effective method of exposing a sound substrate. Once all deteriorated concrete has been removed, a 50 mm x 1200 mm shotcrete repair is applied to the prepped surface.
PERALTA HULK REPAIR
Powell River is home to ten concrete ships, dating back to WW1. They are currently chained together to act as a break water to protect the log storage pond inside. All of the ships have a unique story of glorious days gone by, either as cargo or transport vessels during the wars. The Peralta is the largest in the group, dating back to 1921 and weighing in at 3,696 tons.
The storms in the area cause damage to these Hulks, requiring regular repair, maintenance, and repositioning once a year. The ships are held in place with 16-ton concrete anchors (between 8 and 10).
This location came with a number of difficulties to overcome, including the close marine environment and the limited workspace on the local barge that acted as a work platform.
Our work included prepping the surface and shotcrete application to the deteriorated areas of the S.S. Peralta.