Water Jetting is primarily used to enable pile installation with pile pressing techniques into ground conditions that otherwise would be unsuitable due to either dense sands/gravels or stiff clays. A secondary benefit of water jetting is to significantly improve the rate of pile installation and hence reduce costs, as well as optimising the sheet pile section required.
Water jetting is carried out via a high-strength steel jetting lance pipe attached to the inside of the sheet pile ‘pan’, as shown right.
The jet is operated at low pressures in the initial stages of the installation. The jet is operated continuously throughout the installation to maintain a clear jet nozzle and the pressure adjusted in response to the ground resistance to enable the optimum penetration of the pile to be achieved with a minimum disturbance to the structure of the ground.
- Enables pile pressing into difficult soils e.g. very stiff clays and granular strata
- Improves installation rates
- Optimises pile section choice for better economy
- Very short term disturbance to the soils
- Can also be used with water jetting