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Lancang Lahu Autonomous County Lancang old factory galena located in southwest Yunnan Province, has a long history of mining. In recent years, with the resources of deep mining, ground pressure is increasing, resulting in the mining of transport through the soft rock roadway (tuff roadway) deformation and failure worsening tuff has low compressive strength, deformation, pressure fast water easily expansion deformation destruction, seriously affecting the mining and transportation of the mine soft rock roadway deformation and failure has caused a huge threat to the life of mine production and mine safety, mine soft rock roadway the study of the deformation and failure mechanism has become essential. In this paper, the Lancang old factory galena tuff roadway as the main object of study, through on-site geological survey, representing a comprehensive study of the geological background, geological and mining engineering background, and summed up the tuff in each roadway distribution. Using engineering analogy method, first the classification criteria of the Water Resources and Hydropower rock strength, mine tuff (C15) is divided into soft rock, based on previous experience analogy shows that low compressive strength, soft rock, prone to deformation and failure; followed by Genesis type tuff divided into secondary types, based on previous experience analogy we can see, the secondary rocks is the product of the role of long-term weathering, hydration, strength is very low, prone to deformation and failure; followed by the engineering classification tuff divided into high stress expansion and strong expansion composite soft rock, tuff more susceptible to deformation and failure under high stress and swelling role; tuff rock RMR classification is divided into Class V rock, the class rock seriously affected by the geological structure, water easily deformation, is an engineering poor quality rock mass. Using microscopic analysis, analysis of deformation mechanism of the old factories and mines area tuff tuff mineral composition, the nature of water management, internal and external expansion. Tuff roadway deformation mechanism from a microscopic point of view, and proved tuff deformation mechanism is closely related to its own mineral composition, the nature of water management, internal and external expansion and other factors. Mechanical analysis, according to the site survey, summed up the tuff Roadway in; calculated FLAC modeling, tuff roadway excavation stress redistribution, the first to be squeezed to stress, the two sides roadway rock the two to help sink extrusion floor deformation and failure led to the kick drum, kick drum deformation is proportional to the amount of subsidence and help, the Lancang old plant galena tuff roadway destruction of the kick drum and lateral extrusion with the simulation results are basically the same.
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