Hydrodemolition is the controlled removal of concrete and other structural materials using high-pressure water. This engineering method is useful as a technique for removing damaged concrete from structures during restoration and repair.
In this article we will cover:
What is Hydrodemolition?
The earliest human-made water jets were used for the purpose of material removal in mining applications, particularly for removing soil and accessing valuable ore via hydraulic mining. In the modern construction industry, water jets are used for de-clogging sanitation pipes; cleaning industrial surfaces; cutting rocks, minerals, glass, and ceramics; stripping paint and lacquer; and more. The specific water jet technology used for removing, cleaning, and demolishing concrete substrate and reinforced concrete structures is known as hydrodemolition, or hydroblasting. The flexibility and power of this technology makes it particularly important for structural rehabilitation, like bridge and road infrastructures or commercial pools and amenity decks.
Hydrodemolition Videos
Hydrodemolition at the Florence Water Treatment Plant – Crews used hydrodemolition to remove an old layer of concrete at a water treatment plant in South Carolina. The resulting rough texture allows a new concrete surface to be poured.
Using Hydrodemolition to Remove Concrete While Preserving Rebar – The high pressure of water jetting allows degraded concrete to be removed from structures while leaving rebar intact. This saves both time and money in structural repairs.
Hydrodemolition for Bridge Repair – The 10,000-40,000 pounds per square inch (psi) of pressure saves contractors both time and money by allowing roadways to be demolished and resurfaced without the need for jackhammers.
Hydrodemolition for a Dam Expansion in Colorado – The work to raise the height of a dam involves removing the top 3 inches of existing concrete, which allows new concrete to bond to the old concrete when poured. The machine used for this project produces 20,000 psi, which is ten times the power of a household power washer at 2,000 psi.
Hydrodemolition Concrete
Hydrodemolition of concrete is a cost-effective and time-saving technique to refresh, rebuild, and rehabilitate any concrete surfaces. This technology utilizes the natural permeability of concrete to create an overpressure, which breaks the substrate apart. As seen in the second video above, hydrodemolition can blast through entire blocks of concrete, even beyond the surface layer, while salvaging the internal supporting structure of rebar. Because the hydrodemolition removes rust and scale from the rebar, the metal rebars can be assessed for structural soundness or corrosion. The minimal vibrational output is an additional benefit of hydrodemolition over other methods, particularly pneumatic demolition with jackhammers, which can cause microfractures in surrounding materials as well as soft tissue damage for the jackhammer operators.
Hydrodemolition Equipment
Hydrodemolition is completed using handheld or robotic machines, which vary in size and use case. Ideally, the machine should be automated, which reduces the need for human involvement and labor costs while increasing safety at the work site. Each hydrodemolition machine is built with the use case in mind, from larger machines used for demolishing horizontal road surfaces to compact machines that can fit into an opening less than three feet wide to robots designed specifically to deconstruct a vertical concrete column. Newer technology allows for customization in attachments, such as a kit designed specifically to demolish tunnels and enclosed spaces from the inside out.
