Design, development and performance evaluation of a tractor-mounted bevameter

The tractor-mounted bevameter consists of a main frame, an instrument box which contains the hydraulic and electrical components, a leveling system that applies a safe load vertically onto the soil, sinkage plates with three different shapes to characterize the soil pressure-sinkage relationships, and a carrier supporting the bevameter unit and sinkage plates. The accuracy of the displacement and force measurements were +/- 0.01 mm and +/- 2 N, respectively. A laptop data acquisition and a software tool were used to assist in real-time measuring, recording the applied loads, and the resulting sinkage of the plate during the field sampling operation. The experiments were carried out at a penetration rate 3 cm/s for sinkage plates. Field tests of the tractor-mounted bevameter unit were conducted with three different types of the sinkage plates. Statistical analysis and graphs produced from collected data showed that the shapes of the sinkage plates had considerable influence on the soil parameters. Soil sinkage is affected by the shape of sinkage plates. The values of k(c) and k(phi) are affected by the values of p, z and b. (C) 2010 Elsevier B.V. All rights reserved.