Abstract In order to study the creep properties of mica-quartz schist which belongs to thinly laminated rock in Danba hydropower station,uniaxial creep tests of mica-quartz schist specimens which the loading directions are parallel(0°),perpendicular and 30° to schistosity planes are performed with the computer controlled triaxial creep test machine RLW–2000. Based on the test results,the creep laws of different orientations are investigated. Then,the effects of schistosity planes on creep laws of mica-quartz schist are analyzed. According to the characteristics of creep curves,the modified Nishihara model is used to identify the creep of mica-quartz schist;the parameters of modified Nishihara model are obtained by fitting the data of creep tests;and the fitting results coincide with the test data. Furthermore,the test results reveal that the long-term strength of mica-quartz schist in three loading directions is 60%–70% of uniaxial compressive strength. These studies can provide an important guidance for future study of mica-quartz schist in Danba hydropower station.
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Received: 10 April 2010
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