Geotechnical Laboratory
Geotechnical Laboratory comes into begin in 1955, in Warsaw by Rakowiecka Street. Since 1971 the Geotechnical Laboratory is located in Campus SGGW, by Nowoursynowska Street in the Building of Faculty of Civil and Environmental Engineering (33).
The roots of Modest Geotechnical Laboratory reach early ninetieths when it was starting. Since then, it has enriched its ability to carry out various kinds of tests, and in recent years the laboratory increased to large extent its capability for doing most advanced geotechnical and geoenvironmental tests.
In order to characterize laboratory potential below are briefly named basic groups of tests carried out in the Geotechnical Laboratory.
CLASSIFICATION TESTS
– sieve and hydrometer analysis
– equipment for determination of water content
– Atterberg limits
– organic matter content
– soluble salt content
– calcium carbonate content
– total and solids density.
COMPACTION TESTS
–proctor test (standard and modified)
– equipment for determination of densities rdmax and rdmin.
HYDRAULIC CONDUCTIVITY TESTS
– apparatus for determination hydraulic properties in controlled stress state and degree of saturation
– apparatus for determination of soil water potential
– set up for determination of loss of pressure and silting up pipelines working in drainage -irrigation regime
– TRAUTWEIN system for determination of hydraulic conductivity in fine grained soils used for the mineral liners
– GUELP pressure infiltrometer
– apparatus MAKS for hydraulic conductivity measurement under soil volume change controlled
– system for hydraulic conductivity determination of soil by constant volume method.
COMPRESSIBILITY TESTS
-oedometer tests by incremental loading IL, and continuous loading CRS (1.6 MPa i 30 MPa of vertical stress)
– oedometer UPC with induced negative pore water pressure (suction pressure).
SHEAR STRENGTH TESTS
– direct shear box (standard and large diameter samples)
– standard triaxial apparatus for consolidation and shear strength tests carried out against back pressure
– apparatus for testing samples of 25 cm in diameter is also available
– GEOTAC triaxial system with automatic loading frame.
STRESS-STRAIN TESTS AT SMALL STRAIN LEVEL
Advanced triaxial apparatus equipped with
– internal proximity transducer system for measurement of small strain stiffness
System for measurement of local deformation makes possible direct (inside triaxial cell) measurement of specimen deformation at any phase of triaxial test. Use of the system reduces influence of non uniformity of strain and stresses state on obtained results. Very high sensitivity and of proximity transducers (1 micron) and good repeatability and stability of readings make possible to determine the evaluation of moduli which refer to very small strain range 10-3 %. Principle of the method rests on a change in eddy currents field caused by aluminium target displacement. Aluminium target is rigidly connected to a specimen what enables to register smallest change in a specimen’s geometry. The Figure on the right above shows a cell assembled with ten proximity transducers arrangement which makes possible a measurement of vertical and horizontal deformation of a specimen. Each transducer is connected to a computer through modulator/demodulator. Setting of each transducer’s position is done by specially design devices installed inside the cell. The Figure on the right shows details of vertical deformation measurement.
– system for electrical conductivity measurement
– system for body wave velocity measurement.
GEOMEMBRANE AND GEOTEXTILE TESTS
Laboratory set up for determination of friction forces at soil – geosynthetic material contact
– apparatus for determination of transversal permeability of geosythetics
– apparatus for evaluation of susceptibility of geotextiles for silting up mechanically with soil particles
– oedometer adjusted for measurement of change in thickness of geotextile under loading.
DEVICES FOR MEASUREMENT OF CONTAMINATED SOILS PROPERTIES
– digital conductometer CC-317
– digital pH-meter CP-315
