DSMAC stands for Discontinuous Shear-Crack Initiation and Propagation. It is a term commonly used in the field of rock mechanics and rock engineering to describe a failure mechanism where rock masses fracture and fail along pre-existing discontinuities under shear loading conditions.
In DSMAC, the discontinuities in rock masses such as joints, faults, bedding planes, or other structural planes act as potential failure planes. When shear loading is applied to the rock mass, shear cracks initiate and propagate along these discontinuities rather than through intact rock. This phenomenon is attributed to the fact that the strength of rock across its intact material is usually much higher compared to the strength along existing fractures.
DSMAC is a crucial concept in understanding the mechanical behavior of rock masses, as it has significant implications for engineering design, stability analysis, and failure prediction in rock slopes, underground excavations, and other geotechnical applications. The occurrence of DSMAC greatly influences the stability of rock structures, and accurate evaluation of the strength and deformation characteristics of discontinuous rock masses is necessary for engineering projects in such environments.
Researchers and engineers employ various techniques like laboratory testing, field observations, and numerical modeling to study and simulate DSMAC behavior. Understanding the critical stress conditions, crack initiation, and propagation patterns, and the influence of water, stress states, and other factors on DSMAC is crucial for effective rock engineering and infrastructure development in rock-dominated regions.
