季节性冻土地区高铁路基冻胀规律及防治对策研究

哈大高铁是世界上首条投入运营的新建高寒季节性冻土地区高速铁路。通过对哈大高铁路基冻胀监测数据综合分析，研究了路基冻胀发展变化规律，结果表明:路基冻胀发展包括初始波动、快速发展、稳定维持和融化回落期4个阶段，最大冻结深度普遍大于标准冻深；冻胀变形总体可控并趋于稳定，冻胀变形主要集中在表层级配碎石层，较高的路基含水率加剧了冻胀变形。建议后续路基冻胀防治应对设计冻深根据填料类别等因素进行修正，采用路基基床级配碎石掺水泥不冻胀整体结构，将冻胀观测结果作为沉降评估的重要依据。

Study on Frost Heave Law of High-speed Railway Subgrade in Cold Regionsand Its Preventive Countermeasures

Harbin-Dalian high-speed railway is the first new-built and operating high-speed railway in cold seasonal frozen soil regions in the world. By analyzing the monitored data, the development and changing rules of the frost heave were summarized. The results show that the development of the frost heave includes initial fluctuation stage,the rapid growing stage, the stable frost heaving stage and the thawing settlement stage. Compared with the standard frost depth, the maximum subgrade frost depth is generally 1arger. The frost heave deformation of roadbed is generally controllable and tends to be stable. The frost heave deformation of roadbed is mainly concentrated in the surface graded gravel layer, and the higher moisture content of roadbed aggravates it. It is suggested that the following measures should be taken to prevent frost heave, such as correcting the freezing depth of design according to the filling type and other factors, adopting the whole structure of subgrade bed graded macadam mixed with cement without frost heave, and taking the frost heave observation results as an important basis for settlement evaluation.