敦白高速铁路路基冻胀规律及冻害成因

Freezing Heave Laws of Dunhua-Baihe High Speed Railway Subgrade and Causes of Freezing Damage

随着有砟轨道高速铁路的相继开通运营,出现了一定程度的冻害问题,给高速铁路的养护维修工作带来了更大的挑战。本文结合敦白(敦化—白河)高速铁路所处区域气候环境、设计标准,针对其开通以来发生的路基冻胀问题,通过对动态、静态检测数据统计分析,总结路基冻胀规律,初步研究冻胀成因,提出防治对策。结果表明:敦白高速铁路全线路基冬季存在不同程度的冻胀问题,冻融循环期长达5个月,初步分析路基发生冻害的主要原因为线路所处地理位置气温低、入冬前降雨多导致基床含水率高、基床表层级配碎石水泥掺量低,导致表层冻害数量较多。建议采取强化疏排水、不良填料改性、填料强化置换等措施在夏季、秋季进行综合整治,以减少或消灭冬季冻害,降低冬季现场作业频次。

With the successive operation of high speed railways with ballasted tracks,there has been a certain degree of frost damage,which has brought greater challenges to the maintenance and repair work of high speed railways.This article combined the climate environment and design standards of the Dunbai(Dunhua-Baihe)railway area,and focuses on the subgrade frost heave problem that has occurred since its operation.Through statistical analysis of dynamic and static detection data,the law of subgrade frost heave was summarized,and the causes of frost heave are preliminarily studied,and prevention and control strategies were proposed.The results show that there are varying degrees of frost heave problems in the subgrade of the entire Dunbai high speed railway in winter,with a freeze-thaw cycle period of up to 5 months.Preliminary analysis shows that the main reasons for frost damage to the subgrade are low temperature in the geographical location of the route,high rainfall before winter leading to high moisture content of the subgrade,and low content of graded crushed stone cement in the surface layer of the subgrade,resulting in a large number of surface frost damage.It is recommended to take comprehensive measures such as strengthening drainage,modifying poor fillers,and strengthening replacement of fillers in summer and autumn to reduce or eliminate winter frost damage and reduce the frequency of on-site operations in winter.