无砟轨道线间路基防水封闭层伸缩缝病害整治研究

伸缩缝的密封处理是高速铁路无砟轨道综合防水系统的重要结构组成，伸缩缝的设置长度和密封材料是发挥封闭层作用的重要控制环节。以运营4年的西北寒区某高铁为研究对象，分析了高速铁路无砟轨道线间路基防水封闭层病害是因伸缩缝施工横向未贯通而导致伸缩缝失效，引起封闭层上拱、破裂等影响行车安全。为此，研究制定了线间路基防水封闭层伸缩缝病害排查技术要求，选择了硅酮类嵌缝密封材料，采用了天窗时段切缝、清缝、嵌缝等整治措施。通过上述技术要求和整治措施的实施，整治后运营未出现类似病害。

Study on the Sealing Disease Treatment of Waterproof Sealing Layer of Subgrade between Lines of Ballastless Track

The sealing treatment of expansion joint is an important structural component of ballastless track comprehensive waterproof system of high-speed railway. The setting length of expansion joint and sealing material are important control links to play the role of sealing layer. Taking a high-speed railway in the cold northwest of China that has been in operation for 4 years as the research object, this paper analyzes that the damage of the waterproof sealing layer of subgrade between the lines of ballastless track of high-speed railway is caused by the failure of the expansion joint due to the transverse non-passthrough of the construction of the expansion joint, which causes the upper arch and fracture of the sealing layer to affect the driving safety. Hence, the disease checking technical requirements for the expansion joint of waterproof sealing layer of the subgrade between the lines are studied and developed; the silicone caulking sealing materials are selected and such treatment measures as skylight time frame cutting, joint cleaning and caulking are adopted. Through the implementation of the above technical requirements and treatment measures, similar diseases have not appeared in the operation after remediation.