This study aims to verify the suitability and reinforcement behavior of newly designed bored piles with retaining walls (BPRWs) for cutting-slope stabilization in the Tibet Plateau. As the first BPRWs prevention works in the alpine and hypoxic areas, full-scale performance testing is conducted of the high cutting slopes along the Lhasa-Nyingchi Railway under construction. Amid the construction processes of slope excavation and BPRWs installation, the overall structural performance, including lateral displacement, bending moment and lateral earth pressure, was determined to evaluate the cutting-slope stability and retaining mechanisms of BPRWs. The monitoring parameter distribution rules were thoroughly analysed. The relationship between the lateral earth pressure and pile displacement was studied, and a soil resistance calculation model was proposed. Finally, the BPRWs suitability was assessed. The results revealed that the retaining behaviour of BPRWs is closely related to the construction process. The displacement rate over time is characterized by alternating peaks and valleys, and the maximum displacement rate and bending moment occurs at the retaining wall pouring stage. The bow-shaped bending moment distribution with the pile depth exhibits low values on both ends and a high value in the middle. The ground reaction coefficient is allometrically attenuated with increasing lateral displacement. The proposed soil resistance model can satisfactorily predict the lateral earth pressure. The BPRWs deformation satisfies the service requirements at the construction and service stages. This case study provides a reinforcement reference for BPRW in alpine and hypoxic areas.

本研究旨在验证新设计的带挡土墙钻孔桩（BPRWs）在青藏高原稳定边坡的适用性和加固性能。作为在高海拔和低氧地区进行的第一批BPRWs预防工程，对正在建设中的拉萨-林芝铁路沿线的高挖斜坡进行了全面的性能测试。在边坡开挖和BPRWs的施工过程中，确定了整体结构性能，包括侧向位移，弯矩和侧向土压力，以评估BPRWs的边坡稳定性和固位机理。全面分析了监控参数分配规则。研究了侧向土压力与桩位移之间的关系，提出了土抗力计算模型。最后，评估了BPRW的适用性。结果表明，BPRWs的保持行为与施工过程密切相关。随时间变化的位移特征在于峰和谷交替出现，并且最大位移率和弯矩出现在挡土墙浇筑阶段。带有桩深的弓形弯矩分布在两端显示较低的值，而在中间显示较高的值。地面反作用系数随着横向位移的增加而异速衰减。所提出的土壤阻力模型可以令人满意地预测侧向土压力。BPRW的变形满足了施工和维修阶段的维修要求。