CHEN Shi, HU Huai-gang, HU Da-wei, et al. An adaptive continuous scratching testing technology for rock core[J]. 2025, 46(10): 3302-3314+3328.DOI: 10.16285/j.rsm.2024.1423.
Accurate and rapid acquisition of rock strength parameters is essential for ensuring safety in rock engineering. Conventional methods
including cutting and coring
end face polishing
and compression crushing
are time-consuming. This study introduces a continuous rock core scratching technique as a fast and convenient alternative
causing only minor surface scratch. This method allows for the rapid determination of uniaxial compressive strength
internal friction angle and cohesion. To address the limitations of traditional fixed-depth scratching methods that ignore rock core surface roughness
this study introduces a real-time adaptive adjustment technology. This innovation precisely senses surface characteristics and adjusts scratching depth dynamically. Corresponding adaptive continuous scratching equipment has been developed. A series of continuous scratching experiments was conducted on tight sandstone using three modes: fixed depth
adaptive equal division
and adaptive point selection. Results indicate that
compared to standard compression tests
the maximum error in rock strength parameters from the adaptive scratching test was 10.57%. Furthermore
compared to fixed-depth scratching
the accuracy of uniaxial compressive strength testing using adaptive equal division and adaptive point selection scratching improved by 44.44% and 53.09%
respectively. The study also discusses the sources of strength testing errors caused by different scratching modes and clarifies the applicable scenarios for sharp and blunt cutting heads. Core adaptive continuous scratching test technology provides a simple and efficient new method for rapid testing of rock mechanics parameters
optimizing load measurement errors resulting from traditional methods’ inability to ensure constant actual scratching depth.