Using image analysis to measure two-dimensional soil deformation

A system for measuring two-dimensional deformation in a soil bin using video image analysis was developed and evaluated. Soil was placed in the bin [1.22 (wide) x 9.1 m long] in 50 mm deep layers of nominally uniform bulk density (1.35 Mg m(-3)) to a total depth of 0.76 m. White polypropylene markers [6.4 (dia.) x 25.4 mm] were placed in the soil such that vertical rectangular cross-sectional grids were exposed by removing selected bin modules. Video image analysis was used to determine vertical and horizontal coordinates of each marker which, in turn, were compared to measurements using a sonic digitizer which were accurate to +/- 0.5 mm. (C) 1997 ISTVS.