Localized deformation and instability is the focal point of research in mechanics. The most typical problem is the plastic analysis of cylindrical bar necking and shear band under uniaxial tension. Traditional elasto-plastic mechanics of infinitesimal deformation can not solve this problem successfully. In this paper, on the basis of S(strain)-R(rotation) decomposition thorem, the authors obtain the local strain distribution and progressive state of axial symmetric finite deformation of cylindrical bar under uniaxial tension adopting nonlinear gauge approximate method and computer modeling technique.

Compared with the strain definitions of finite deformation, the defects of Green strain and polar decomposition theorem have been pointed out. Based on the additive decomposition theorem, which was established by Prof. Chen Zhida, the nonlinear gauge method being fit for the numerical simulation is presented. This method combines the Ritz-Galerkin approximate method together with visualization and is a new extension of residual method. The numerical example demonstrate that this method can obtain the results approach to practical phenomena and is an effective and feasible approach to solve the large deformation of mining subsidence.

Observations in the

The occurrence of minc accidents such as fire and gas explosion always causes great loss of estate. So it is very important to quickly conrol the accident situation and correctly make rescue. GIS-based mine safety decision support system (abbreviated for “MGIS system”) can find the best escaping route and rescue route through shortest route analysis and loop analysis, also determine the fire influence area and fire source through connectivity analysis and ancestor tracing analysis. And it can determine all exits and blast holes to be closed so as to implement closing quickly when the fire is hard to be controlled.