• The buildings of the IfG Leipzig - Südwerkbunker (left) and the Kauengebäude (right)

    The buildings of the IfG Leipzig - Südwerkbunker (left) and the Kauengebäude (right)

  • The rock mechanical laboratory of the IfG Leipzig

    The rock mechanical laboratory of the IfG Leipzig

  • Drilling cores of the Leine rock salt (Na3)

    Drilling cores of the Leine rock salt (Na3)

  • Dimensioning

    Dimensioning

  • Large-diameter borehole experiment in Springen

    Large-diameter borehole experiment in Springen

  • Modelling of a cavern

    Modelling of a cavern

  • Subsidence over a	cavitary field (modelling)

    Subsidence over a cavitary field (modelling)

Rock mechanical laboratory

The departments of rock mechanics, field measurments and modelling of rock behaviour are equiped with modern tolls and supplies for work, which allow rock mechanical tests according to the state of science and technology.

For the rock mechanical laboratory investigation are following technical equipment available at the IfG:

  • Climatised rooms for storage of the samples equal to the in situ conditions (defined and constant temperature as well as air humidity)
  • Devices for mineralogical-petrographical sampling, determination of density and humidity, supersonic measurement and photo documentation
  • Workshop with extensive facilities for the true to size sample preparation according to the testing requirements (stone saw, band saw, fixed and mobile drilling rig with several drill diameter, turning machines etc.)
  • Workshop for construction of special design and internal development of measurement technology for underground use or rather for use in the rock mechanical laboratory
  • Rock mechanical research and test laboratory with :
    • Servo-hydraulical testing system Schenk-Trebel RBA 2500 (max. axial load: 2,5 MN - year of construction: 1984, basic modernize in 2007) with two triaxial cells for confining pressure up to 100 MPa as well as testing temperature in the range of 295 - 393 K; ability for test specimens up to 110 mm diameter and 220 mm length - combined permeation or transmission with p- and s-waves possible
    • Servo-hydraulical testing system GL TestSystems D2000 (max. axial load: 2,0 MN - year of construction: 2011) with the same triaxial cells (see above) resp. for performance of uniaxial compression test as well as backfill compression tests with the large testing cell (d = 520 mm; l = 800 mm, 170 l capacity - strain gauges for the determination in 4 measurement planes)
    • Servo-hydraulical testing system SHM 250 (max. axial load: 250 kN - year of construction: 1985, basic modernize in 2009) with several triaxial cells (sample: 40mm diameter and 80mm length) for confining pressure up to 50 MPa as well as testing temperature in the range of 295 - 393 K,a backfill compression cell with measurement of axial load and the building up side pressure (diameter 155 mm, max. filling height 350 mm) and equibment for bend testing, direct and indirect tensile tests, uniaxial compression test as well as compaction tests in the small compaction cell (ca. 6 l capacity - strain gauges for the determination in 2 measurement planes)
    • Servo-hydraulical MTS shear test system modell 816 (year of construction: 2003) for direct shear test on bulk samples (max. axial load 500 kN, max. horizontal shear force 250 kN pressure or minus 160 kN tension) for cuboid samples with a maximum shear plane of 200 mm x 200 mm or cylindrical samples with a diameter of 150 mm and a length of 300 mm; possibility of variable assembly (tipped samples)
    • Hydraulical material testing system WPM (max. axial load 5 MN) with force and displacement control, compaction cell (diameter 500 mm, max. filling height 800 mm) with measurement of the building up side pressure as well as a real triaxial cell for cubed samples with a edge length of 100 mm
    • 50 testing rigs for creep tests in climatised laboratory with triaxial cells for testing at constant compression or extension strain as well as testing temperature in the range of 295 - 413 K (sample dimension 40 x 80 mm); additional 6 testing rigs for larger sample dimension (size 60 x 120 mm)
    • QUIZIX pump system for permeation tests with pulse-free fluid injection (e.g. gas, brine) at constant rate (max. rate: 7.5 ml/min; min. rat 0.0000007 ml/min) or constant pressure (max. pressure: 51 MPa)
    • "Hydrogen laboratory" with 6 creep testing rigs (sample size 60 x 120 mm) with the possibility of permeability test using hydrogen (alternative nitrogen, methane and/or helium) under triaxial loading; determination of the gas permeability k up to 10-21 m²
    • Three 5 meter high acrylic glass columns (diameter of 25 cm) for analysis of the subsidence behavior, uplift, etc. as well as the permeability of dry or wet crushed salt or other backfill materials

Following standard or modified test types (on costumer requests) can be conducted at the IfG own rock mechanical laboratory:

  • TC - triaxial compression test - routine with dilatancy measurements (with variations, e.g. with increased temperature, drained/undrained/pore pressure application as well as with ultrasonic wave velocity transmission measurements and/or permeation)
  • TC-MS - triaxial compression test in multi-stage technology
  • TE - triaxial extension test
  • TC-PE - triaxial compression test with determination of the permeability (using diverse gases and fluids)
  • TC-R - triaxial compression test with embedded relaxation phase
  • UC - uniaxial compression test (with radial strain measurement)
  • SV - direct shear test (under constant normal stress, constant stiffness resp. as test without dilatancy; a video you find here)
  • DTT - direct tension test
  • MTT - modifid tension test
  • SZ (BRA) - indirect tension test (BRAZIL test)
  • TCC - long term creep test under triaxial compression
  • TEC - long term creep test under triaxial extension
  • QD -swelling pressure test with the determination of solution permeability
  • VD - backfill compression test (drained/undrained) - force/displacement control
  • CT - backfill test in the column (permeation, subsidence, uplift etc.)
  • PM - pillar modell with uniaxial compression (a video you find here)