RQD

Definition

RQD, or Rock Quality Designation, is a measure used to assess the quality and integrity of rock cores obtained from drilling, indicating the degree of jointing or fracture in the rock mass.

Purpose

The purpose of RQD is to provide a quantitative assessment of rock quality, helping geologists and engineers determine the suitability of rock for construction, mining, and other engineering projects.

Examples of Use

• Geotechnical engineers use RQD to evaluate the stability of rock for tunnel construction.
• Mining companies assess rock quality using RQD to plan safe and efficient extraction processes.
• Civil engineers utilize RQD data to design foundations and other structures that interact with rock masses.

Related Terms

• Core Sample: A cylindrical section of rock obtained through drilling for analysis.
• Fracture: A break or crack in rock, affecting its strength and stability.
• Geotechnical Engineering: The branch of engineering dealing with the behavior of earth materials.

Notes

RQD is expressed as a percentage, with higher values indicating better rock quality. It is an essential parameter in rock mechanics and geotechnical investigations.