为了研究周期水压力对岩石的变形特性，利用MTS815岩石力学多功能试验机，对砂岩试样进行了不同轴向应力(峰值强度σmax的60%、70%和80%)条件下孔隙水压力循环试验，还运用Matlab中小波分析对岩石变形曲线中常见的不规则小变形波动干扰曲线进行处理。试验结果表明：随着恒定轴向应力的增大，周期水压力作用下疲劳变形将加速岩石的破坏；随着孔隙水压力循环次数的增加，塑性滞回环呈疏—密—疏的变形演化过程；运用小波分析方法对周期水压力作用下砂岩受多种因素的干扰的变形曲线进行分解、重构处理及评价，从而得到最优分解尺度的基本曲线较好的吻合了试验曲线，更好的揭示了岩石变形的演化规律。

To explore the characteristics of deformation of sandstone under cyclic pore water pressure, the experiments with different axial stresses (60%, 70% and 80% of peak intensity) of sandstone subjected to cyclic pore water loading are investigated by using MTS815 rock mechanics testing system, and irregular small deformation in deformation curve of sandstone are also processed by wavelet transformation of Matlab. The results show that with the increase of constant axial stress, fatigue deformation under cyclic pore water pressure will accelerate the failure of the sandstone. With the increase of the number of cyclic pore water pressure, the deformation evolution of the plastic-loop is illustrated as sparse-dense-sparse. The deformation curves of sandstone under cyclic pore water pressure affected by many factors are decomposed, reconfigurable processed and evaluated by using wavelet transformation, which indicates that the basic curve with optimal decomposition scale fits well with the experimental curves and reveals the deformation evolution of sandstone.

国家自然科学基金资助项目(50974141);国家重点基础研究发展计划(973计划)项目(2011CB201203);重庆大学“211工程”三期创新人才培养计划建设项目(S-10220)