TY  - JOUR
A1  - Milatz, Marius
T1  - An automated testing device for continuous measurement of the hysteretic water retention curve of granular media
Y1  - 2020-02-11
VL  - 15
IS  - 8
SP  - 2239
EP  - 2257
JF  - Acta Geotechnica
DO  - 10.1007/s11440-020-00922-y
PB  - Springer Berlin Heidelberg
N2  - The water retention curve (WRC), representing an important key for the modelling of hydro-mechanical behaviour of unsaturated soils, is still not fully understood, because it originates from microscopic hydraulic and capillary phenomena. Furthermore, its experimental measurement, especially for cyclic drainage and imbibition paths, is challenging and time-consuming. In this contribution, a recently developed low-cost easy-to-use miniature testing device for the investigation of the WRC of unsaturated granular soils, such as coarse-grained sand and a packing of glass beads, is presented. With the help of the new device, that can be controlled by a Raspberry Pi single-board computer, the hysteretic WRC can be investigated in a conventional macroscopic approach by plotting the macroscopic specimen degree of saturation versus measured matric suction. The test set-up allows an automatic measurement of the WRC which is measured continuously following a programmed test procedure. In addition to the technical realisation of the new device, this contribution focuses on macroscopic results of water retention tests. Moreover, the testing device has been designed in a miniaturised size, in order to obtain microscopic insights into the phase distribution during cyclic drainage and imbibition paths with the help of computed tomography in future applications.
UR  - http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/10594
ER  -