Natural soils often exhibit rotated transverse anisotropy due to various geological processes (e.g., tectonic movement, filling and soil deposition), and the trend of soil strength usually changes with depth. This study combines rotated transverse anisotropy with non-stationary random field (RF) to investigate the reliability and failure mechanism of a slope under undrained conditions. Two scenarios of non-stationary RF are considered: (a) the trend of soil strength increases along depth; (b) the trend increases along the direction perpendicular to bedding. It is found that the expected performance levels of slope reliability would be significantly different under different directions of the trend. When the undrained shear strength increases along the direction perpendicular to bedding, the changes of slope reliability and sliding consequence would be sensitive to the dip angle of strata. Besides, the failure mechanism can be affected by the direction of the trend and strata orientation. Generally, shallow failure is more likely to occur on the dip slope when soil strength increases along the direction perpendicular to bedding, while for reverse slope with soil strength increasing perpendicularly to the bedding, deep failure mechanism is significantly dominant.

由于各种地质过程（例如构造运动，填充和土壤沉积），天然土壤通常表现出旋转的横向各向异性，并且土壤强度的趋势通常随深度而变化。这项研究结合了旋转横向各向异性与非平稳随机场（RF），以研究不排水条件下边坡的可靠性和破坏机理。考虑了两种非平稳的RF情景：（a）土壤强度沿深度增加的趋势；（b）趋势沿垂直于铺垫的方向增加。结果发现，在趋势的不同方向上，边坡可靠度的预期性能水平将显着不同。当不排水的抗剪强度沿垂直于顺层的方向增加时，边坡可靠度和滑动结果的变化将对地层倾角敏感。此外，破坏机理可能受趋势方向和地层方位的影响。通常，当土体强度沿垂直于地层的方向增加时，在倾角坡上更可能发生浅层破坏，而对于土体强度垂直于地层的垂直方向增加的反向坡，深部破坏机理占主导地位。