Investigating the mechanical properties of layered rock mass is essential for ensuring the safety, stability, and efficiency of engineering projects such as tunnels, slopes, dams, and foundations. Layered rock masses often exhibit complex behaviors due to the presence of bedding planes, joints, and varying material compositions. These features significantly influence how the rock mass responds to stress, deformation, and failure. Understanding mechanical properties helps engineers predict how the rock will behave under different loading conditions. This is particularly important in layered formations, where anisotropy can lead to unexpected failures if not properly accounted for. Furthermore, accurate characterization of these properties supports the design of effective support systems and excavation methods, reducing construction risks and costs. It also aids in assessing long-term stability, especially in regions prone to seismic activity or weathering. In geotechnical engineering, neglecting the mechanical behavior of layered rock masses can result in catastrophic failures, environmental damage, and financial loss. Therefore, this book is not only a scientific necessity but also a practical requirement for sustainable and safe infrastructure development.