JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech IV Year ROCK SLOPE TECHNOLOGY Previous Question Paper (July/August - 2022 - R16)

The primary objectives of a geological investigation for a slope are to define the site's geological framework and assess its stability. These include:

• Identifying the lithology and stratigraphic sequence to understand the physical and mechanical properties of the rock mass.
• Mapping structural discontinuities such as faults, joints, bedding planes, and shear zones, which often dictate the failure mode of the slope.
• Determining the hydrogeological conditions, including groundwater levels, pore water pressure, and permeability, as these significantly influence slope stability.
• Evaluating the in-situ stress state and the degree of rock weathering or alteration.
• Providing essential data for geotechnical modeling and the design of stabilization measures such as drainage, reinforcement, or slope geometry optimization.

A mine slope is characterized by several geometric parameters that define its stability and safety. The diagram conceptually consists of a series of benches forming an overall slope angle.

Key parameters include:

• Bench Height (H): The vertical distance between the crest and the toe of an individual bench.
• Bench Face Angle (β): The angle of the individual bench face measured from the horizontal.
• Bench Width (W): The horizontal distance between the crest of one bench and the toe of the bench above it.
• Overall Slope Angle (α): The angle formed by the line connecting the crest of the top bench to the toe of the bottom bench.
• Catch Bench: A wider bench designed to catch falling debris or rockfall.

In a diagram, the slope is represented as a stepped profile where the bench height and width determine the overall inclination. The stability is heavily dependent on the ratio of these parameters relative to the geological discontinuities present in the rock mass.