Available Online: http://www.ejpau.media.pl/volume14/issue4/abs-06.html
FLOW-PUMP TECHNIQUE AS A CONSTANT VELOCITY METHOD OF FLOW MEASURMENT IN SOFT ORGANIC SOILS
Department of Geotechnical Engineering, Warsaw University of Life Sciences - SGGW, Poland
In this paper the results of the relationship between pore pressure differences and time obtained in laboratory flow-pump technique tests in soft organic soils are presented.
The Soil-Water Characteristic is necessary to predict and calculate the real amount of vertical and horizontal deformations which depend on consolidation process and are relatively large in soft organic soils. The consolidation curve is changeable with the different values of load. In the deformation process of soil skeleton, under loading, the porosity decreases and causes the changes of permeability characteristics. Considerable differences in flow parameters between soft, cohesive and uncohesive soils demand to use various methods of water flow measurement in the subsoil under the engineering constructions. The laboratory methods for permeability measurement should model the main course of in-situ flow for fully saturated soils.
Because of very week organic soils structure and specific properties, such as, high porosity, low shear strength and high initial permeability which decrease during consolidation, the method of flow measurement should be suitable. The results obtained in flow-pump laboratory tests indicated that the constant velocity method is very optimized and proper to measure the flow parameters in soft peats.
Key words: water flow characteristic, consolidation process, deformations, organic soils, peat.
Department of Geotechnical Engineering,
Warsaw University of Life Sciences - SGGW, Poland
Nowoursynowska Str. 159, 02-776 Warsaw, Poland
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