Railway electrification offers significant benefits in terms of decarbonisation at the point of use and reduced traction costs. However, to realise these benefits, the fixed infrastructure must be provided at an affordable cost. Recent schemes in the UK have seen the cost of railway electrification soar: one of a number of reasons for this has been the substantial increase in mast foundation pile lengths compared with historic practice. The paper explores this through a comparative review of traditional and modern pile design methods. In addressing the ultimate limit state, the various approaches are shown to give broadly consistent results in terms of pile length. However, increased pile lengths will be calculated if three-dimensional effects are not allowed for in limit equilibrium (ultimate limit state) calculations, or if a serviceability limit state calculation is carried out using unrealistically low soil stiffness. The results of the comparative analyses should give designers the confidence to use the traditional empirical approach, or a limit equilibrium calculation without the need for an explicit serviceability limit state check (as permitted by Eurocode 7) using potentially inappropriate soil stiffness parameters.

中文翻译：

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铁路架空线设备桅杆基础设计

铁路电气化在使用时在脱碳方面具有显着的优势，并降低了牵引成本。但是，要实现这些好处，必须以可承受的成本提供固定的基础结构。英国最近的计划已经看到了铁路电气化的成本飞涨：许多原因之一是与历史实践相比，桅杆基础桩的长度大大增加了。本文通过对传统和现代桩设计方法的比较回顾来探索这一点。在解决极限极限状态时，各种方法在桩长方面显示出大致一致的结果。但是，如果在极限平衡（极限极限状态）计算中不考虑三维效果，则将计算增加的​​桩长，或如果使用不切实际的低土壤刚度进行使用寿命极限状态计算。比较分析的结果应使设计人员有信心使用传统的经验方法或极限平衡计算，而无需使用可能不合适的土壤刚度参数进行明确的使用寿命极限状态检查（如欧洲规范7所允许）。