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A new method for evaluating the rock mass damage index based on the field point load strength
Lei Wen1, Zhou Quan Luo1, Shi Jiao Yang2
1School of Resources and Safety Engineering, Central South University, Changsha 410083, Hunan, People's Republic of China.
Royal Society Open Science
|April 30, 2019
Summary
A new method using field point load strength accurately calculates the rock mass damage index. This approach is vital for assessing rock strength and deformation in engineering projects.
Area of Science:
- Geotechnical Engineering
- Rock Mechanics
- Civil Engineering
Background:
- Rock mass strength and deformation are critical in civil, geological, and mining engineering.
- The damage index is a key parameter controlling these rock mass properties.
Purpose of the Study:
- To propose a novel method for computing the rock mass damage index.
- To validate the new method using empirical relations and experimental testing.
Main Methods:
- Developed a strength ratio using point load strength (PLS) of pre-existing joints and intact rock failure.
- Conducted experimental tests including P-wave and on-site point load testing.
- Performed linear regression analysis to correlate the new damage index (D) with the integrality coefficient (K).
Main Results:
- Established a relationship between the damage index and the integrality coefficient.
- Demonstrated the new method's sensitivity to plasticity and damage in rock masses.
- Validated the proposed damage index computation method through experimental data.
Conclusions:
- The new point load strength-based method provides a reliable estimation of rock mass damage.
- This method is effective for evaluating rock masses in underground excavation and tunnel engineering.
- The findings contribute to improved rock mass characterization and engineering design.
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