An Introduction to Hydro-demolition

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An Introduction to Hydro-demolition

• The safer way to remove concrete

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Hydro-demolition

• Hydroblasting, alternatively known as
  hydro-demolition is used for a variety of
  applications including removing asphalt and grout
  from a large assortment of structures and
  materials. Introduced within 1970s, this method
  of concrete blasting is one of the most widely
  used techniques of the modern age. Differing
  water pressures, variable flow rates, and a vast
  array of equipment and settings ensure that a
  high degree of knowledge and expertise are vital
  to achieve optimal results.
• The benefits of hydro-demolition manifest
  themselves in a variety of safety and applied
  features. One of the major benefits of
  Hydro-demolition is safety. Safety is paramount
  within the construction industry, and
  hydro-demolition is one of the most effective and
  safest techniques for removing debris,
  contaminants and concrete from structures and
  roads. Reduced vibration ensures minimised risk
  to the operator from conditions such as
  Vibration-Induced White Finger (VWF), or Hand-Arm
  Vibration Syndrome (HAVS). Hydro-demolition is
  also one of the most cost effective ways to
  remove defective concrete without damaging the
  unaffected area.

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Hydro-demolition Uses

• Hydro-demolition has a very impressive range of
  uses throughout the construction industry, the
  following will highlight just a few -
• Hydro scarification
• Partial Depth Removal
• Full Depth Removal
• Hydrocleaning

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Hydroscarification

• Hydroscarification utilises high pressure water
  to partially remove the top surface of concrete
  on roads and other structures. Usually this is
  undertaken to a nominal depth of between 1/4 to
  3/4 of an inch. The end result delivers a
  micro-fracture-free surface to ensure a strong
  bond when pouring new concrete. Hydro
  scarification increases the lifecycle of roads
  and bridge surfaces by reducing the need for
  total replacement this in turn reduces labour
  and raw material expenditure.

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Partial Depth Removal Full Depth Removal

• Partial depth removal or partial depth patching
  involves the identification and removal of
  localised deterioration. Once an area has been
  identified, the area is then restored to an
  acceptable standard. Areas are squared off and
  are marked roughly 3 inches beyond the weakened
  zone. Debris is removed, the area is cleaned of
  dirt, grime and foreign objects and only then new
  surface area is laid. Partial depth removal is
  particularly useful for concrete restoration
  projects where entrenched items need to be
  conserved.
• When concrete has reached a state of advanced
  deterioration, cracks and possible contamination
  are serious concern, full depth removal becomes
  an option. Full depth removal is used to expose
  structural elements of decking, roads or any
  other road or concrete surface, without damaging
  the surrounding uncompromised concrete. Full
  depth removal is particularly useful where
  precast beams have been used within structures
  including bridges and parking complexes.
  Hydro-demolition can remove concrete from beams
  without fracturing the overall structure.

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Hydroblasting

• Hydrocleaning or hydroblasting is amongst the
  most common of mechanical cleaning techniques,
  utilising water pressure of up to 5000 psi to
  remove dirt, grime, oil, paint, rubber, sealants,
  foreign bodies and contaminants from surfaces of
  all shapes and sizes. Hydrocleaning is a cost
  effective, environmentally friendly and a highly
  effective method of cleaning.

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Saftey

• When working with such high pressures safety is
  absolutely paramount. Therefore, operators must
  be trained, competent and adhere to stringent
  health and safety practices when working with
  such specialised equipment. All operators working
  with hydro-demolition must wear proactive
  equipment including reinforced footwear,
  gauntlets, ear defenders, protective eye wear,
  shin guards body armour and a hard hat.

Graham Urquhart is a concrete specalist hwo
writes for Corecut, the UKs leading provider of
diamond drilling contractors, concrete removal
and wire sawing.