Block sampling of soils: Some practical consideration

Block sampling of soils can produce samples of the highest quality. However during block sampling attention has to be given to a number of practical aspects to minimize disturbance to the material. Mechanisms by which disturbances can be introduced include strains imposed to samples during the act of sampling, swelling, stress relief and moisture content changes during storage. This paper discribes a number of techniques to obtain block samples. Techniques referred to include sampling the soil from test pits, auger holes and tunnels as well as down hole block sampling under high water table conditions. Themechanisms by which disturbance to samples can occur are discussed, and practical guidelines to minimize the level of disturbance are suggested.