|
|
The Penn State rock mechanics lab has a state-of-the-art, servo-hydraulic biaxial testing apparatus. The vertical load frame has a maximum force of 1MN and the horizontal frame can produce forces up to 800kN. Each load frame may be operated in displacement- or load-feedback servo control. Displacement control resolution is 0.1 micron for each axis and load resolution is <0.1kN. The apparatus is powered by a 20 GPM, 50 hp hydraulic power supply. Servo-controlled load point displacement rates of 0.01 micron/s to 2 cm/s are possible.
The apparatus is set-up primarily for double direct shear
friction studies and is capable of normal stresses up to 40 MPa on samples
of nominal contact dimension 15 cm x 15 cm. Machine stiffness is
roughly 4 MN/cm and therefore ideal for friction and fracture studies.
Animation of Apparatus used in Double-Direct Shear Configuration
Animation of Apparatus with Pressure Vessel
For more information contact: Prof.
Chris Marone
Current Research
Mechanics of the critical slip distance and application of laboratory data to seismic faulting The rate of fault healing and implications for friction constitutive laws Numerical studies of earthquake nucleation and dynamic rupture propagation Numerical modeling of friction data and inversion for friction constitutive parameters Upper stability transition on mature faults and the mechanics of earthquake afterslip Frictional behavior of smectite and illite-rich clay gouges with application to the mechanics of subduction zone megathursts Influence of grain characteristics on the friction of granular shear zones The effect of humidity on granular friction Creep and frictional behavior of laboratory fault zones subject to time-dependent fluctuations of normal and shear load Friction and shear heating at high velocity Effect of shear load, including true stationary contact, on frictional healing Effect on frictional healing of loading rate and accumulated displacement