3D Laser Scanning Sampling Interval for Rock Joint Roughness

The patent applies parameter changes by establishing a functional relationship between sampling interval and joint roughness coefficient (JRC). Through theoretical derivation and experimental verification, the patent determines optimal sampling interval parameters (e.g., 0.5mm, 1.0mm, 2.0mm) that balance measurement precision and processing efficiency. The method transforms the roughness evaluation from a qualitative assessment to a quantitative parameter-based determination, where the sampling interval is selected based on the derived formula and verified through scatter plot analysis and fitting equations.

The patent replaces mechanical contact measurement systems with optical 3D laser scanning systems. Instead of using physical instruments like needle outline rulers that require direct contact with the rock joint surface, the invention employs laser-based non-contact scanning technology to acquire point cloud data. This substitution eliminates safety hazards associated with manual measurement on high and steep cliffs while maintaining high measurement precision through optical field interaction with the rock joint surface.

The patent applies preliminary action by pre-establishing the theoretical relationship between sampling interval and JRC through derivation and experimental verification before actual roughness evaluation. The optimal sampling interval parameters are determined in advance through scatter plot analysis, fitting equations, and verification experiments. This preliminary work creates a ready-to-use theoretical framework and parameter set that can be directly applied in subsequent measurements, eliminating the need for trial-and-error selection while ensuring measurement precision.