Rock testing mainly intends to mimic stress conditions that a sample of rock is exposed to in nature. It is done to prevent geotechnical failure by measuring the behavior of rocks for compliance with regulations, design blueprints, and quality control standards. It considers important parameters like elastic modulus, stress, poisons ratio properties, strain to evaluate specimen. The rock testing equipment like the triaxial deformation apparatus is used to test the rock sample. Slopes, tunnelling, dam foundations, and surface constructions require the characterization of associated rocks and the interpretation of their reaction to induced stresses. When a sample of rock is directed to specified stress situations in the laboratory, the nonlinear connections, even for very small strains, hysteresis, etc. can be given by a stress-strain diagram.
What is triaxial deformation apparatus?
The triaxial testing apparatus was invented for conducting experimental studies on deformation, fracture, and frictional sliding of rocks to examine geophysical and geological phenomena. In triaxial apparatus, gas, liquid, or solid material is used as the pressurizing medium, and either gas or solid material is mostly used at high temperatures. It is rock testing lab equipment that uses a confining medium like kerosene or argon to apply consistent pressure around a sample. Successful triaxial tests on rock samples need a mechanism of providing a constant confining pressure. The hydraulic ram can then apply differential stress. The confining pressure and the pore pressure within the sample are examined by intensifiers.
How triaxial deformation apparatus works?
A rock sample is held inside the triaxial deformation apparatus between metal blocks. It reflects the movement of two sides of a fault moving against each other. The machine compresses and pushes against the sample. After that, the sample slipping is recorded. The definite hydraulic valves control the machine. It ensures that consistent stress is applied to the sample throughout the experiment, irrespective of the change or shift in the movement of the sample during the process. The effects are measured in the lab measures, and their meaning is interpreted.
The rock samples that are used in the experiment differ in size and composition. Rock bits are eroded due to friction caused because faults slip and slide against each other. Thin layers of crunched-up rock are formed. Triaxial deformation apparatus is used to study the deformation of gouge during a fault slip. A thick layer of the gouge is formed after the fault matures. The gouge layer’s strength would control the fault slip. For a dynamic slip, an earthquake occurrence, the slip might require confining on a thinner gouge layer. As to warm our hands, we rub them together. Similarly, a lot of heat is produced by faults when they slip. A large spike in the temperature is caused due to friction between the two surfaces. This increased temperature can modify the organic molecules within the rock faults.
This is how the rock samples are tested. There is some rock testing laboratory equipment suppliers in India that deal in superior quality rock testing equipment.