Rock Mechanics

How rock behaves when we dig into it. The science of rock stability: intact rock properties and lab tests, rock-mass classification (RQD, RMR, Q, GSI), in-situ stresses and stress around openings, rock-slope stability for open pits, and ground support design with bolts, cables and shotcrete.

• Rock Properties & Testing — Rock strength and stiffness control every excavation. Learn uniaxial compressive strength (UCS), tensile strength (Brazilian test), Young's modulus and Poisson's ratio, the point load index test and its size correction, density and porosity, and the complete stress–strain curve of rock.
• Rock Mass Classification — Rock masses are intact blocks separated by joints. Learn RQD, Bieniawski's RMR, Barton's Q-system (RQD/Jn × Jr/Ja × Jw/SRF), GSI, how they are measured from core and mapping, correlations between them, and how Q gives unsupported span and support requirements.
• In-situ Stress & Openings — Rock deep underground is squeezed by the weight above and tectonic forces. Learn vertical and horizontal in-situ stresses, the stress ratio k, stress measurement, the Kirsch solution for stresses around a circular opening, stress concentration, spalling and rockbursts.
• Rock Slope Stability — Open-pit walls fail along joints and faults. Learn failure modes (planar, wedge, toppling, circular), kinematic analysis, the planar-failure factor-of-safety equation with cohesion, friction and water pressure, acceptance criteria, and slope monitoring and depressurisation.
• Ground Support — Ground support keeps underground openings safe. Learn rock bolts (mechanical, resin, friction, cable bolts), mesh and shotcrete, dead-weight bolt design, empirical bolt length and spacing (Q-system rules), support for burst-prone ground, and quality control.