Seven large scale dynamic tests of rock support were conducted at LKAB’s KiirunavaaraMine in order to develop a methodology for the design of dynamic load resistant rocksupports. The tests were performed to increase the understanding of the response of rocksupport installed on the walls and roof in a tunnel and subjected to strong dynamicloading. The tests were originally numerically simulated by using two numerical tools,LS-DYNA and UDEC, in a former PhD Project at Luleå University of Technology, LTU(Shirzadegan, 2020), to investigate the performance of the test set up, the response ofsupported and unsupported excavations during the field tests as well as the complexinteraction of stress waves and rock support. The comparison of the numerical results andthe results obtained from field tests showed that the combination of LS-DYNA and UDECcould satisfactorily simulate the field tests. This work is the continuation of the LTUproject with LS-DYNA and UDEC.Since the analyses were previously conducted with 2D models, while in reality thestructural geology, ground motion measurements, fracture investigations and supportmotion, as well as the deformation measurements, occur in a 3D space, in the presentproject three-dimensional analysis are carried out using 3DEC that can assist in studyingthe interaction of the dynamic load with rock joints, rock blocks, tunnel wall and installedrock support. In this project the analyses are carried out in two stages: (i) the explosionstage is modelled in 3D with the finite element code LS-DYNA and (ii) the wavepropagation stage is modelled in 3D with the program 3DEC, where the results from LS-DYNA are used as input.The numerical simulations in this project can be used to analyse the behaviour of rockmasses and rock support systems under dynamic loading conditions. These simulationsprovide valuable information about the response of the rock mass to dynamic loading andcan be used to optimize the design of rock support systems. The numerical results evaluatedifferent rock support performance (Swellex Mn24 bolt and D -bolt) under dynamicloading conditions.3DEC modelling in the present study shows that: a) numerically calculated velocitypatterns match well those observed in the field for Test No. 6, b) larger displacementsoccurred for certain rock blocks in the unsupported crosscut and, c) the patterns of themost displaced rock blocks in the model very much resemble the positions where falloutswere observed in the field close to the footwall drift in the unsupported crosscut. (PDF) Dynamic modelling of rock bolts at Kiirunavaara mine.