Empirical estimation of rock mass deformation modulus of rocks: comparison of intact rock properties and rock mass classifications as inputs

Abstract Deformation modulus of rock mass (Em) is an important parameter for the analysis and design mining engineering projects. However, field tests measuring deformation are difficult, time-consuming, capital intensive. This has led to development numerous empirical models estimating modulus, which in different forms scattered literature. The available literature use types inputs. Therefore, this study provides a comprehensive compilation masses. compiled grouped based on their type input parameter(s) into three categories such as those using intact properties, classification indices, combination properties indices. Then, comparative was performed absolute average relative error percentage (AAREP) variance accounted (VAF) assess reliability inputs estimation masses data from two sites. results analyses show that indices most reliable among considered analyses. For AAREP illustrative examples study, (7 out 10) Em have best performances with values ranging 24.07 55.15%. VAF examples, (8 59.81 88.11%. lowest errors highest deviation similarities indicate they produce estimations Em. It note estimated depends quality differently across sites used study. therefore performance evaluation guidelines selecting appropriate model mass.