Measuration Of Geostress And Forecast Of Rock Burst For OneTunnel

The Tunnel is existent lifeline of Drung Nationality Living in Yunnan province inChina. The tunnel is located in the Hengduan Moutain where not only crustalmovements and medium scale earthquakes now always happen but also withcomplicated geological conditions and neotectonic movements violently. Duringtunnel’s excavation proplems which will affect the stability of surrounding rock such ascomplicated geological conditions, active fault, violent earthquake, high geostress, rockburst, and geological hazards of slope are always found out. Construction progress isslow because values and directions of geostresses given by geological data are differentfrom physical truth which leads into rock burst. So lt is naccessary to mesure geostressaccurately and make rock burst prediction. This paper based on the excavation of thetunnel makes some researchs, and some conclusions are obtained as follows:①Values and directions of geostress are acquired by overcore method stress relieftest using KX-81hollow inclusion stress cell at K1+585and K6+003state mark of thistunnel.②Acoustic emission test is exterted to the samples gained from field, and resultsof Kasiser are comparied with stress relief measurement ones. One conclusion can beobtained that results of acoustic emission and stress relief tests are similar, and proveseffectiveness and accuracy of the two ways.③Accorting to the actual parameters and size of standard tunnel section of thisTunnel, three-dimensional numerical model is established by using ABAQUS–one kindof numerical simulation software. The location and severity of rock burst may occur aregiven based on the criterion of rock burst of the Engineering Rock Mass ClassificationStandard in our country.④Monitoring results of rockburst of this tunnel are almost the same withrockburst prediction, which proves that the prediction of rockburst can be used to guidethe construction of this tunnel.The results of this paper, which have guiding value for the construction of theTunnel, will speed up the schedule of thisproject.