砂卵砾石料变形与强度特性三轴试验研究

对不同密度的某砂卵砾石料试样进行了三轴固结排水剪切试验,研究了密度对砂卵砾石料强度、应力应变性质的影响。结果表明,随密度的增大,试样的强度指标呈增大趋势;不同围压下,随密度的增大,破坏时的轴向应变具有减小的趋势,且在低围压下这种趋势较明显;密度越大,试样的剪胀性越强,发生相变时的轴向变形和体积变形越小;试样发生相变时的应力水平一般大于0.5,因此在对高土石坝进行应力变形分析时应合理考虑粗粒土的剪胀性。

Triaxial Test Study of Deformation and Strength Behaviour of Sand-gravel Materials

The influence of densities on strength and stress-strain properties is studied by doing triaxial consolidation-drained shear tests on the different densities of sand-gravel materials. The results show that with the density increasing, the strength index of samples significantly increases; At different confining pressures, with the density increasing, the failure axial strain tends decreases; moreover, this trend is obvious under the condition of low confining pressure; the greater the density is, the stronger the dilatancy of test samples is, and the smaller the axial strains and volume deformation is; the stress level is greater than 0.5 at the state of phase change. It is suggested that the dilatancy of coarse-grained soil should be taken into account in the analysis of the stress and strain of high earth-rockfill dam.