Method for evaluation of geological strength index of carbonate cliff rocks:Coupled hyperspectral-digital borehole image technique  

作　　者：Haiqing Yang Guizhong Huang Chiwei Chen Yong Yang Qi Wang Xionghui Dai 

机构地区：[1]Key Laboratory of New Technology for Construction of Cities in Mountain Area,School of Civil Engineering,Chongqing University,Chongqing,400045,China [2]National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas,Chongqing,400045,China [3]Technology Innovation Center of Geohazards Automatic Monitoring,Ministry of Natural Resources(Chongqing Institute of Geology and Mineral Resources),Chongqing Engineering Research Center of Automatic Monitoring for Geological Hazards,Chongqing,401120,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第10期4204-4215,共12页岩石力学与岩土工程学报（英文）

基　　金：supported by the National Key R&D Program of China(Grant Nos.2021YFB3901403 and 2023YFC3007203).

摘　　要：The deterioration of unstable rock mass raised interest in evaluating rock mass quality.However,the traditional evaluation method for the geological strength index(GSI)primarily emphasizes the rock structure and characteristics of discontinuities.It ignores the influence of mineral composition and shows a deficiency in assessing the integrity coefficient.In this context,hyperspectral imaging and digital panoramic borehole camera technologies are applied to analyze the mineral content and integrity of rock mass.Based on the carbonate mineral content and fissure area ratio,the strength reduction factor and integrity coefficient are calculated to improve the GSI evaluation method.According to the results of mineral classification and fissure identification,the strength reduction factor and integrity coefficient increase with the depth of rock mass.The rock mass GSI calculated by the improved method is mainly concentrated between 40 and 60,which is close to the calculation results of the traditional method.The GSI error rates obtained by the two methods are mostly less than 10%,indicating the rationality of the hyperspectral-digital borehole image coupled evaluation method.Moreover,the sensitivity of the fissure area ratio(Sr)to GSI is greater than that of the strength reduction factor(a),which means the proposed GSI is suitable for rocks with significant fissure development.The improved method reduces the influence of subjective factors and provides a reliable index for the deterioration evaluation of rock mass.

关 键 词：Hyperspectral image Digital panoramic borehole image Geological strength index Carbonate rock mass Quantitative evaluation 

分 类 号：TU45[建筑科学—岩土工程]