Abstract: The caving property of ore and rock mass is a key factor determining whether the natural caving method can be
smoothly implemented. To address the issues of difficulty in obtaining some parameters and the large discreteness of evaluation
scores in the caving property evaluation methods,an improved Rock Mass Rating (RMR14) method was developed and applied
to the caving property evaluation of a copper-gold mine. Firstly,based on the RMR14 method,it was found that the rock variability
parameter was difficult to obtain and had a functional relationship with the uniaxial compressive strength (USC) of the
rock. The corresponding score could be obtained through the rock's uniaxial compressive strength. Secondly,by comprehensively
analyzing the weights of each evaluation index and performing function fitting between each evaluation index and the evaluation
score,continuous value acquisition was achieved,solving the problem of large discreteness in the RMR14 evaluation scores and
improving the RMR14 method. A three-dimensional digital model of the copper-gold mining area based on the improved RMR
evaluation system was constructed using 3DMine software,and each block of the block model was evaluated by Kriging interpolation
based on the geological drilling data set to form an overall caving property analysis model of the evaluation area. Finally,
the caving property was evaluated from the perspectives of elevation and lithology,respectively,to form a multi-level and allround
evaluation system. The research results show that the overall caving property grade of the copper-gold mine obtained by
the improved RMR method is grade Ⅲ,with an improved RMR comprehensive score of 52. 97,which belongs to the medium
caving level. Compared with the traditional RMR14 method,the improved RMR method can ensure the accuracy of the final evaluation results even when some parameters are missing,providing an important reference for the evaluation of engineering
rock mass quality.