System dynamic behavior of high-speed railway infrastructure on multilayered soils considering soil nonlinearities

考虑土壤非线性的多层土壤上高速铁路基础设施的系统动态行为

• 批准号: 392201168
• 负责人: Professor Dr.-Ing. Frank Rackwitz
• 金额: --
• 依托单位: National Natural Science Foundation of China
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/392201168?language=en
• 关键词: System; dynamic; behavior; speed; railway

The objective of the proposed project is to develop models for prognosis of train-track-soil behavior due to high speed trains (velocity over 400 km/h), to evaluate existing infrastructure in the context of infrastructure stability by a train speed increase and to propose vibration reduction remedies. An improved understanding of the physical phenomena associated with transmission of vibrations induced by high speed trains and variation of soil properties at resonance-like state and the ability to model in the most realistic way potentially problematic locations would allow us to propose cost effective mitigation measurements. Along these lines, an advanced theoretical and numerical model for the train-track-soil interaction will be developed in an attempt to study the dynamic behavior of railway infrastructure and the surrounding soil. A detailed train-track-soil mechanical model and the accompanied numerical tool will be constructed taking into account the nonlinear behavior of the track and the soils under dynamic load induced by high-speed train passage. Multilayered geological profiles will be taken into consideration with soft soil material and discontinuities. The following mechanical aspects of the problem will be thoroughly investigated: i) inelastic and poroelastic behavior of the soft soil stratum under high-speed train passage, (ii) wave energy localized distribution and propagation from high-speed railway in the infrastructure and inhomogeneous soil foundation, iii) critical velocity of the train which leads to resonance condition and response amplification of the track and the soil foundation, and (iv) variation of soil properties at resonance state induced by high speed train loading. The developed numerical tool will be validated and where necessary updated based on in-situ measurements conducted by the applicants in a test site of the cooperation partner in China, where high speed railway constructed on various subsoils is in operation. Various in-situ tests will be performed, measured data will be collected and soil samples from the test site will be tested to obtain their strength and deformation characteristics. By means of in-situ and laboratory investigations, an efficient numerical tool for prognosis and evaluation of high-speed train infrastructure will be developed for practical applications.

拟议项目的目标是开发高速列车(速度超过400公里/小时)引起的列车-轨道-土壤行为的预测模型，在列车提速的基础设施稳定性的背景下评估现有基础设施，并提出减振补救措施。更好地理解与高速列车引起的振动传输和类似共振状态下土壤性质变化相关的物理现象，以及以最现实的方式对潜在问题位置进行建模的能力，将使我们能够提出具有成本效益的缓解措施。沿着这些线路，将建立先进的列车-轨道-土体相互作用的理论和数值模型，试图研究铁路基础设施和周围土体的动力特性。建立了详细的列车-轨道-土力学模型和相应的数值工具，考虑了高速列车通过时轨道和土体在动载作用下的非线性行为。多层地质剖面将被考虑到软土材料和不连续面。研究内容包括：(1)高速列车作用下软土层的弹塑性和孔弹性特性；(2)高速铁路波能在基础和非均匀地基中的局部化分布和传播；(3)列车的临界速度导致轨道和地基的共振条件和响应放大；(4)高速列车荷载作用下土体性质在共振状态下的变化。开发的数值工具将根据申请人在合作伙伴中国的试验场进行的现场测量进行验证，并在必要时进行更新，在该试验场，在各种地基上修建的高速铁路正在运营。将进行各种现场试验，收集测量数据，并对试验场的土样进行测试，以获得其强度和变形特性。通过现场和实验室研究，将开发出一种有效的高速列车基础设施预测和评估的数值工具，以供实际应用。