Experimental study on deformation of deep unsaturated-saturated Tuff in Lancang lead-deposit
会议名称：《The International Young Scholars’ Symposium on Rock Mechanics》
会议日期：2008年
学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程]
摘 要：正The lithology of Lancang lead-deposit ledge is cataclastic altered *** the wall rock mass of the mine lancway,tuff trader the groundwater table is triable and has characteristics with high rate of moisturc content,low permeability,and variable *** the seepage ficld is changed during the mine exploita- tion process and the interface between watcr and rock mass increases,the tuffis become soft and the strength is decreased and the rate of shrinkage of the laneway is *** cost of the supporting is heightened and the security risk is *** in situ testing of the stress and the deformation monitoring,the deformation of saturated-unsaturated tuff in the deep mine has been *** results are as follows:1)under the condition of tri-axial in situ testing,the strength of tuff can be 23.6 Mpa,the wall rock mass is steady;2)at the very beginning of the mine exploitation process,for the increasing of water-rock interface and the disappearing of one side stress,the strength of tuff decreases suddenly,and the lowest averagc strength is about 2.5 Mpa,which makes the side deformation increased rapidly,and the high strength support is needed for the wall rock mass stability;3)after about 15 d to 30 d,the shrinkage of the laneway is about 30%.With the wcathering,the moisture content of the wall rock mass is decrcasing and the strcngth of the wall rock-tuff is rising again,and some one can be reach to 13 *** rate of deformation is decreased and the wall rock is stabilized *** result can be a theoretic base for design of support wall rock mass.