俄罗斯莫喀高铁抗冻胀基床结构研究

Research on the Anti-frost Subgrade Bed Structure of Moscow-Kazan High-speed Railway in Russia

研究目的:针对沿线低达-48℃的严寒环境和高达400 km的超高时速,俄罗斯莫喀高铁初步设计采用"0.12 m沥青混凝土+0.28 m级配碎石表层+2.3 m底层"的新型防冻胀基床结构。该基床结构在国内尚无大规模应用经验,为确保其安全性和适用性,本文从防冻胀、列车荷载影响以及沥青混凝土封闭层耐久性三个方面展开全面研究。研究结论:(1)依据俄罗斯相关规范进行的冻深计算结果表明:沿线设计冻深为2.1～2.6 m,初步设计所采用的2.7 m基床厚度满足要求;(2)在验算列车荷载影响时,应考虑强度准则、变形准则以及长期动力稳定性准则;计算结果表明莫喀高铁所采用的基床结构安全可靠;与防冻胀准则相比,列车荷载影响并不控制基床厚度;(3)在长期动荷载作用下,0.12 m沥青混凝土封闭层的使用寿命可超过100年,满足莫喀高铁耐久性要求;(4)该研究成果对于其他严寒地区高速铁路基床结构设计具有借鉴意义。

Research purposes： In view of the cold environment low to-48 ℃ and the super-high speed up to 400 km/h,a new subgrade bed structure of ＂ 0. 12 m asphalt concrete ＋ 0. 28 m surface layer ＋ 2. 3 m bottom layer＂ is adapted during the preliminary design of Moscow-Kazan high-speed railway. This structure has not been largely used in China,in order to ensure its safety and applicability,the ability of anti-frost,the influence of train load and the durability of asphalt concrete are studied in this paper.Research conclusions：(1） The calculation of frozen depth of Moscow-Kazan high-speed railway is achieved by following Russian codes,and the result shows that the frozen depth varies from 2. 1 m to 2. 6 m,and the thickness of subgrade bed adapted in preliminary design is 2. 7 m,which meets the requirements.(2） When verifying the influence of train load,the strength criterion,the deformation criteria and the long-term dynamic stability criteria should be considered. The verification results show that the structure discussed is safe and reliable. Compared with the influence of frost,the influence of train load does not determinate the thickness of subgrade bed.(3） Under the influence of long-term dynamic loads,the service life of 0. 12 m asphalt concrete can last more than 100 years,which meets therequirements of durability.(4） This research result has reference value for design of subgrade bed in other cold areas.