The inclined retaining pile is an innovative excavation retaining structure free of internal braces. It can significantly reduce the cost and construction time of excavation. However, the stability of inclined-pile-supported excavations has not been well investigated. Discontinuity layout optimization was used to analyse the failure mode and the influencing factors of the stability of the excavation supported by inclined piles in clay. This shows that overturning failure and overall failure are the two possible failure modes of excavations supported by inclined piles. The failure mode gradually changes from overturning failure to overall failure as the incline angle increases. The stability of the excavation supported by inclined piles is positively correlated with the undrained shear strength and negatively correlated with the weight of the soil, the embedded depth of the inclined pile, the excavation depth ratio and the incline angle, whereas the influence of the excavation width can be neglected. Furthermore, a simple dimensionless formula is proposed based on 11,880 cases covering the most common values of the main influencing factors. It is demonstrated that the formula can predict the safety factor of inclined-pile-supported excavation well.

斜挡土桩是一种创新的开挖挡土结构，无内撑杆。可显着降低开挖成本和施工时间。然而，斜桩支护开挖的稳定性尚未得到很好的研究。采用不连续性布局优化方法分析粘土斜桩支护开挖的破坏模式及影响因素。由此可见，倾覆破坏和整体破坏是斜桩支护开挖的两种可能破坏模式。随着倾斜角的增加，失效模式逐渐从倾覆失效转变为整体失效。斜桩支护开挖的稳定性与不排水抗剪强度呈正相关，与土体重量呈负相关，斜桩的埋入深度、开挖深度比和倾斜角，而开挖宽度的影响可以忽略不计。此外，基于涵盖主要影响因素最常见值的 11,880 个案例，提出了一个简单的无量纲公式。证明该公式可以预测斜桩支护开挖井的安全系数。