The Numerical Analysis Of Strain Localization In Soil

Stain localization is a phenomenon of that strain concentrated in narrow areas when rock or soil is going to damage (shear strain localization is also known as shear band). Strain localization is a well known phenomenon, which can be observed on many kinds of constructions. Strain localization is an important form of expression; it is also an important sign of soil failure.Therefore, the research on shear band is important to evaluate the security and stability of geotechnical engineering structures. According to above elements, the main work and achievements of this paper is as follows:1. To analyze the formation and development of shear band of sand on plane strain with FLAC3D.Then we compared the results of numerical simulation with experimental results.2. The analysis of shear band on sand caused by defects in different locations under plane strain, and then sums the rule of formation of shear band.3. We treat the sand as strain soften materials. Then we analyze the effects of strain softening on stability of tunneling interface through utmost support pressure ratio,X-direction ground subsidence-direction ground subsidence and block state, then compare them with results of hardened.4. To analyze the affects of three softening parameters: friction angle ,dilatancy angle ,cohesion on stability of tunneling interface.We can get shear band on dry sand successfully ,the rule of formation of shear band and the influencing factors.Finally,we analyze the effects of strain softening on the stability of tunneling surface, and concluded that strain localization is important to the stability of construction.