Abstract: This paper introduces the history, development, advantage, disadvantage and the state of the art applications of the airfoam drilling technique. The airfoam drilling is an attractive method in the draught or no water supply areas, slopes or areas near the retaining wall that are sensitive to the water seepage, areas with high environmental requirements and locations with high quality of soil samples. The quantity of the foam additives, control of air and the experience of the driller are critical to the success of the airfoam drilling. This paper introduces the application of the airfoam drilling method in a project in Hong Kong.

Key words: Air-foam Drilling, Water-Saving, Sampling, Geotechnical Investigation