Study On Lagrange Analysis Method For Rock Mechanical Behavior And Its Application In Engineering

In this thesis, Lagrange numerical method of rock mechanical behavior analysis, engineering rock rheology mechanical model and rheological behavior Lagrange analysis method are studied. The main points are as follows.1. Lagrange method of continua mechanical behavior analysis summariesThe current domestic and overseas situation of Lagrange method study and application is summarized.Mechanics background and solving thoughts of Lagrange method for continua mechanical behavior analysis are probed. Basic principles, main formulae, some treatment methods and main calculation steps of FLAC3D are summarized.2. Study on Lagrange analysis method for continua in three dimensions (FLAC3D)Characteristics of FLAC3D are studied, and comparisons between FLAC3D and finite element method are made. The advantages and defects of FLAC3D are pointed out. Difference of calculation results between Drucker-Prager and Mohr— Coulomb yield criterion, influence of dilation angle value, large deformation problem and small deformation problem, precision setting on calculation result are also studied through examples. The research achievements of this part are below:(1) FLAC3D method uses node motion equation and traces the medium motion process from being loaded to reaching equilibrium state. While the finite element method solves from node mechanical equilibrium equation directly. This is the basic difference between the two methods.(2) FLAC3D does not use the real medium damping property and node mass, so the real process experiencing by the medium is not given and the influence of medium motion process on result cannot be reflected rightly. So the physical meaning of calculation result of stress and deformation given by FLAC3D is not very clear.(3) In FLAC3D, the medium vibration during solving process...