Experimental and Statistical Study of High-Pressure Water Jet “Hydro-Demolition Technique” on Concrete for Partial-Depth Concrete Bridge Deck Repair Applications

Water jetting is a cutting technique that has been widely used for cutting different types of material in many industries. In the concrete industry, water jetting is often referred to as hydro-demolition; it is used as a technique to remove deteriorated concrete within transportation infrastructure rehabilitation projects. For partial-depth repair of concrete bridge decks, using the hydro-demolition method to remove the upper half of the deck can cause a major problem known as punch-through. Punch-through is where the high-pressure water makes a full-depth removal instead of partial-depth removal. Punch-through is caused by a lack of pressure control over the cutting depth and is dependent on the concrete properties and the water jet operation parameters. In this study, the hydro-demolition technique is investigated to eliminate the occurrence of punch-through. Experimental and statistical analyses are performed to investigate the effect of high-pressure water on concrete as part of the partial-depth repair of a concrete bridge deck. Small-scale trials of 15 concrete specimens with varying compressive strengths are tested. Statistical analysis for experimental data for abrasive water jets on concrete with different compressive strengths is carried out to develop a predictive model for determining the input parameters to accurately predict concrete removal to a specified depth. The experimental study finds that the water pressure, cutting time, and compressive strength of concrete influence the cutting depth of the water jet. Statistical analysis provides a multi-regression model that can be employed for the prediction and optimization of response parameters of the hydro-demolition technique.