Study on Equivalent Deformation Parameters of Blocky Rock Mass for Tunnel
A stochastic DEM numerical model of tunnel in blocky rock mass was established based on the Voronoi dis-cretization method.The feasibility of using the equivalent deformation parameters of rock mass to predict the tunnel con-vergence deformation was verified by a large number of stochastic numerical calculation results.Based on the calculation method for equivalent deformation parameters of regular jointed rock mass,a modified calculation formula and corre-sponding characteristic parameters were proposed for the tunnel excavation in deep blocky rock mass.The reasonableness of the modified formula was verified by comparing with existing solutions and a large number of random numerical results.The modified formula was suitable to improve the calculation method of equivalent deformation parameters of regular jointed rock masses in reflecting the significant error in deformation estimation of randomly fractured blocky rock masses under tunnel unloading conditions.The equivalent deformation parameters of the rock mass obtained by the modified for-mula method can well predict the mean value of the tunnel convergence deformation after tunnel excavation in the ran-domly fractured blocky rock masses.The proposed modified formula can provide reference value for the current study of rock mass deformation parameters and the estimation of tunnel wall convergence displacement.
tunnel engineeringrock mass deformation parametersdistinct element methodblocky rock masstunnel convergence