WATER-BALANCE IN SWELLING MATERIALS - SOME COMMENTS

Materials ranging from wet tailings in retention ponds through potenti ally acid sulfate sediments in humid marine environments to clay soild s in semi-arid climates shrink and swell with change in water content. This paper discusses the formulation and determination of material ba lance in such swelling and cracking materials. Significant errors and their likely magnitudes are identified when these estimates are based in physical space, as opposed to material space. Ways in which this pr oblem might be dealt with are discussed.