Experience with Hydrodemolition for Bridge Repair

When carrying out repairs to concrete structures, removal of the damaged concrete constitutes a problem in itself. Several different methods can be used to remove damaged concrete. Experience from the use of water-jet cutting, also know as hydrodemolition, as an alternative to the pneumatic hammer, is presented. The term water jet is used to designate the technique that makes use of water jets with extremely high pressure, up to about 400 MPa. The use of water at very high pressure for concrete works in the form of drilling, cutting or hole-making is a technique that has been well known for many years. The new type of water-jet cutting described herein is concerned in the first instance with surface removal of concretes, i.e. hydrodemolition of damaged concrete from undamaged concrete, which is left intact.