The State Council Information Office published on September 27, 2009, a white paper entitled China' s Policies toward Minorities and Common Prosperity and Development of All Nationalities. The white paper says that t...The State Council Information Office published on September 27, 2009, a white paper entitled China' s Policies toward Minorities and Common Prosperity and Development of All Nationalities. The white paper says that the policies well fit the national conditions and are correct. They are instrumental to promoting harmonious coexistence of all nationalities that work with one heart and one mind and in mutual cooperation; they have helped open up a good national situation characterized by economic development, political stability,展开更多
Based on the open stope method,the stability of the gob area was decided bypillars and stiff roof.Therefore,it was dispensable to leave pillars with long-term strengthand enough size to support the stiff roof during m...Based on the open stope method,the stability of the gob area was decided bypillars and stiff roof.Therefore,it was dispensable to leave pillars with long-term strengthand enough size to support the stiff roof during mining activities.Based on the miningconditions of Baixiang wollastonite mine in Changxing County of Zhejiang,while consideringpillars with different shape,irregular size,and distribution,the load imposed on the pillarswas analyzed,and the safety coefficient was calculated in order to determine theirsupport status.The strength of stiff roof was calculated by means of analytical solution-theory of rectangle thin plate rested on elastic foundation.The system stability ofpillar and stiff roof was analyzed according to the proportion of the total cross section areaof pillars to the stiff roof area above the mined area.展开更多
文摘The State Council Information Office published on September 27, 2009, a white paper entitled China' s Policies toward Minorities and Common Prosperity and Development of All Nationalities. The white paper says that the policies well fit the national conditions and are correct. They are instrumental to promoting harmonious coexistence of all nationalities that work with one heart and one mind and in mutual cooperation; they have helped open up a good national situation characterized by economic development, political stability,
文摘Based on the open stope method,the stability of the gob area was decided bypillars and stiff roof.Therefore,it was dispensable to leave pillars with long-term strengthand enough size to support the stiff roof during mining activities.Based on the miningconditions of Baixiang wollastonite mine in Changxing County of Zhejiang,while consideringpillars with different shape,irregular size,and distribution,the load imposed on the pillarswas analyzed,and the safety coefficient was calculated in order to determine theirsupport status.The strength of stiff roof was calculated by means of analytical solution-theory of rectangle thin plate rested on elastic foundation.The system stability ofpillar and stiff roof was analyzed according to the proportion of the total cross section areaof pillars to the stiff roof area above the mined area.