Horizontal seepage and the buffer pond in the cylinder intake rate test

• Published in: Transactions of The Japanese Society of Irrigation, Drainage and Reclamation Engineering Vol. 1988; no. 133; pp. 87 - 92,a2
• Main Author: Shimada, K. (Ishikawa Prefecture Coll. of Agriculture, Nonoichi (Japan))
• Format: Journal Article
• Language: Japanese
• Published: The Japanese Society of Irrigation, Drainage and Rural Engineering 25.02.1988
• Subjects: MEASUREMENT; MEDICION; MESURE; MOUVEMENT DE L'EAU DANS LE SOL; MOVIMIENTO DEL AGUA EN EL SUELO; SOIL WATER MOVEMENT
• ISSN: 0387-2335; 1884-7234
• DOI: 10.11408/jsidre1965.1988.87

The use of a buffer pond in the cylinder intake rate test has been supposed to minimize horizontal seepage below the bottom of the cylinder. This paper discusses the influence of horizontal seepage on the test results and examines the effect of the buffer pond. Finite element simulations for the tests with the cylinders driven 20cm deep were carried out with 6 different soils, following which the results were compared with those of one-dimensional infiltration. The discussion leads to the following conclusions: 1. No buffer pond is necessary for soils whose coefficient of permeability is smaller than 5×10-4 cm/s. 2. For soils whose coefficient of permeability is greater than 5×10-4 cm/s, a) As a 10 cm wide buffer pond is not effective in minimizing horizontal seepage, a wider buffer pond is recommended. b) A buffer pond made of a frame driven into the soil layer is not effective in minimizing horizontal seepage. c) The log (time)-log (cumulatve infiltration) data in which the cumulative infiltration is smaller than 1.5 Dmax should be employed for obtaining the intake constants. Dmax can be obtained from the next equation: Dmax=200 [(Saturated volumetric water content?Initial volumetric water content)](mm)