The Multiscale High-resolution Simulation Of Local Failure And Crack Interaction In Rock Mass

The study of rock failure process and failure mechanism has always been a hot topic in rock mechanics,and is also the basis of engineering stability evaluation.The failure process simulation method based on rock continuum mesoscopic model has attracted much attention due to its strong failure simulation ability.In the past,in order to achieve high-resolution characterization of local failure phenomena such as crack propagation,large-scale global uniform meso-scale units were used,which caused serious space-time calculation burden.The contradiction between high-resolution and high space-time computing burden is becoming more and more prominent! Therefore,a local multiscale high-resolution modeling strategy based on RFPA is proposed in this paper.The high-resolution mesh is used in the region of interest to avoid the large-scale computational burden caused by the global uniform meso-scale mesh.Through the problems of crack propagation and interaction and local failure of tunnel,the progressive failure process of rock was simulated by using multi-scale high-resolution modeling strategy.The main contents and conclusions are as follows:(1)The relevant theories of RFPA and multiscale high-resolution mesh model and the calculation process of multiscale high-resolution simulation are given.Numerical verification of related problems at laboratory scale and engineering scale is carried out.The results compared to theoretical solutions show the computational accuracy of the multiscale highresolution modeling strategy,which lays a foundation for further research.(2)Different downscaling mesh refinement forms and different complexity were simulated at laboratory scale and engineering scale;good calculation results show that the multiscale grid strategy flexibility on encryption scheme choice.This means that the multiscale grid strategy could provide a more effective meshing scheme for simulation related to issues.(3)The studies of simulation show that multiscale high resolution compared to the global uniform grid meshing is greatly reduced the amount of cell.Similarly,in some quantifiable indicators,such as computation time and CPU consumption,running memory size and the file storage of calculation,the multiscale grid strategy shows great advantage.It can effectively avoid the waste of calculation and reduce the cost of calculation,which indicates the high efficiency of the calculation.(4)Through the related problems such as crack propagation and interaction,the local failure of the tunnel under multiple working conditions and the simulation application of actual engineering,the multiscale grid strategy shows a high degree of agreement with global uniform grid scheme,experimental phenomenon and field practice.This shows that the multiscale modeling strategy has a good ability to analyze and simulate the failure of rock and other related problems.This article first has carried on the multiscale high-resolution strategy research based on the RFPA.The good results show its advantages in the application of rock failure,which provides a new solution for the study of rock failure and other problems.