Definition - What does Sandy Soil mean?
Engineers use geotechnical surveys and investigations to reveal the soil types of the ground through which a trenchless project will run. Sandy soil contains small particles ranging from 0.05 to 2-mm in diameter. While sandy soil is the easiest ground to excavate and bore, care must be taken to prevent a collapse of the ground due to inadequate support.
A geotechnical investigation will produce a report that guides engineers on how to proceed with a project and whether or not the ground requires improvement prior to the extensive phases of the project.
Trenchlesspedia explains Sandy Soil
When undertaking an HDD project in sandy soil, it is important to adjust the mixture of the drilling fluid with more bentonite. The porosity of the soil tends to cause the drilling fluid to escape from the bore into the surrounding ground. However, adjusting the drilling fluid mix can seal the bore more effectively and cause the project to be successful.
Sand is also very abrasive, leading to high wear on some components of the drilling rig, especially the drilling head. Pipe ramming is an ideal trenchless method for loose sandy soil because the soil is excavated from within the pipe leaving little opportunity for ground collapse.