Comparison of Continuous and Pulsing Water Jets for Repair Actions on Road and Bridge Concrete

The concrete samples with various erosion states simulating road or bridge damage were disintegrated by pure continuous water jets generated from pressure 380 MPa and by pulsing water jets generated from low pressure 30 MPa. The erosion states of samples were prepared applying several laboratory techniques simulating the concrete aging under the conditions corresponding to the use in practice. The influence of the erosion state on the disintegration rate was tested because water jet techniques are very effective in selective disintegration of damaged concrete without significant erosion of the unbroken concrete unlike pneumatic drills or other impacting machines usually used for such a work. The comparison of both the depth of penetration and the ratio of volume disintegration regarding the input power is performed. All results are discussed regarding their application in practice and further development of special routings.