Rock Mechanics

Specimen preparation and joint behavior require specialized equipment that can prepare rock samples for testing and simulate the conditions under which rocks may fail. 
Most of the information obtained from laboratory tests on rock are primarily related to the stress and strain characteristics of the tested materials.

The most common tests on cylindrical rock samples are the evaluation of the compressive strength and strain under either uniaxial or triaxial conditions.
Uniaxial Test: The uniaxial test is performed by applying increasing vertical stress at a constant rate. Axial and radial strains are measured with high precision. Subsequent load-unload cycles are also carried out to obtain an accurate evaluation of the compressibility properties.
Triaxial Test: The triaxial test is performed on prepared rock specimens which are contained in a rubber sealing membrane and placed within a triaxial chamber.

They are then subjected to a constant isotropic confining pressure. A vertical stress is subsequently applied; tests and measurements are carried out in the same way as for uniaxial tests. These testing equipment and techniques are important tools in geotechnical engineering, helping to ensure the safe and stable design of structures on rock foundations.

Due to the above-mentioned characteristics, rock mechanics can provide valuable data that can inform design decisions and help to ensure the safety and stability of civil engineering structures. By understanding the physical properties and behavior of rocks, engineers can indeed design structures that are optimized for the geological conditions of a given site, ensuring long-term stability and safety.