Automated soil particle size analyzer based on gamma-ray attenuation

Application of gamma-ray attenuation principles permits the determination o f density and water content of a material. Moreover, this technique also al lows one to determine particle size distribution, when particles are fallin g in a liquid medium according to Stokes' law. Based on these principles, c omputerized equipment was developed to perform a fully automatic analysis o f soil particle size distribution. This equipment's main advantage is the c apability to analyze ten soil samples automatically, each one in Is min, th e resulting output is a complete curve of soil particle size distribution, ranging from 2 mum to 2 mm. Another feature of this equipment is its fast s oil granulometric fraction analysis fat ten samples per h), which determine s the fractions of clay, silt, and sand. Results obtained with the gamma-ra y technique showed an excellent correlation with the pipette method. (C) 20 01 Elsevier Science B.V. All rights reserved.