High temperature conventional triaxial compression test of shale were carried out by using the MTS815 ser- vo-controlled testing machine, based on the results of the tests, the relationships between confining pressure and the characteristic of shale stress-strain curve, peak strength, elastic modulus, Poisson' s ratio, peak strain were investigated, and the general regulation is obvious. According to the characteristics of volumetric strain, the stress-strain curves were classified into three types. They are dilatation type, compression-dilatation type, compression type, and the confining pressure has conspicuous dilatation effect on shale. At the same temperature, when confining pressure rises from 5 MPa to 25 MPa, shale peak strength (σ1- σ3 ) is comparatively lower, indicating stronger plastic deformation, and peak strength and elastic modulus increase with uprising confining pressure. When confining pressure is lower than 15 MPa, shale Poisson' s ratio increases with increasing confining pressure while peak axial strain and peak circle strain decreases with increasing confining pressure. When confining pressure is higher than 15 MPa, shale Poisson' s ratio decreases slightly with the increasing confining pressure, while peak axial strain and peak circle strain increase slightly with the increasing confining pressure.%利用MTS815型程控伺服刚性试验机对页岩开展高温常规三轴压缩试验,基于试验结果分析围压与页岩应力-应变曲线特征、峰值强度、弹性模量、泊松比、峰值应变的关系。结果表明,按体积应变特征,应力-应变曲线可归为3类：扩张型、压缩-扩张过渡型和压缩型,围压对页岩具有较明显的扩容作用。在同一温度时,在5～25 MPa围压范围内,页岩峰值强度（σ1-σ3）较低,表现出较强的塑性变形破坏特征,峰值强度和弹性模量具有随围压增加而增大的趋势。围压小于15 MPa时,页岩泊松比随围压增大而增大,而峰值轴向应变和峰值横向应变均随围压增加而逐渐降低;围压大于15 MPa后,泊松比随围压增加呈小幅下降,峰值轴向应变和峰值横向应变随围压增加而略有增大。
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