Factors affected the rock mass shear strength parameters are complex with uncertainties. A comprehensive model with multiple index is established combined with quantitative and qualitative indicators. It can effectively determine the shear strength of rock. The multivariate nonlinear statistical method is introduced to study the rock mass shear strength parameters. Twelve qualitative and quantitative indicators are selected

based on the large number of projects through the collection of data

nonlinear explicit equations of cohesion

and friction angle for rock mass shear strength are established; their determining coefficients are 0.992 729

0.999 998

respectively. This model not only considers quantitative factors

but also considers qualitative factors. It is verified by field data. Results show that the models have high accuracy. It is easy to solve the rock mass shear strength parameters with high practical value

and it has high practical value for projects.