盾构隧道整体道床脱空病害整治技术应用研究

轨道交通道床结构病害主要包括开裂和脱空两类。其中，道床脱空病害会威胁行车安全、降低行车稳定性和轨道结构使用年限，影响乘客的舒适性、平稳性和安全性，更降低地铁的可靠性和耐久性，增加轨道结构的养护维修费用，对运营行车安全造成极大的威胁。受结构设计形式的制约，盾构隧道内的道床更易出现道床脱空病害。本章主要介绍了盾构隧道整体道床病害产生的原因及道床加固、道床综合整治和道床翻修三类道床病害治理方法的适用条件和优缺点。同时，以北京地铁机场线T2 三元桥区间盾构隧道道床病害综合整治工程为研究背景，详细介绍了道床综合整治方法的四个关键技术难点：湿环境作业条件下，注浆材料的亲水性和黏接性要求较高；道床板抬升的设备及监测控制要求高；轨道设施整治控制要求高；道床综合整治完成后，恢复正常行驶速度控制严。结合现场施工实际情况，对施工准备、施工过程和施工效果进行了详细介绍。文章的研究内容可以为城市轨道交通类似道床病害治理工程提供参考依据。

Treatment technology of monolithic ballast disengaging in shield tunnel

 Cracking and disengaging are the main diseases of rail transit. Between them, the latter is a great threat to operating driving safety, which will threaten the driving safety and stability, shorten the service life of the track structure, and affect passenger comfort. Due to design constraints, the ballast in the shield tunnel is more prone to occur disengaging disease. In this paper, the causes of the monolithic ballast disease of the shield tunnel are described. The applicable conditions, advantages and disadvantages of the maintenance methods including reinforcement, comprehensive improvement and renovation are summarized. Based on the comprehensive treatment of the Beijing Metro Airport Line from T2 Airport Building to Sanyuanqiao, four key technical points of the comprehensive treatment method for the monolithic ballast are introduced in detail. Results show that the requirements for the hydrophilicity and adhesion of grouting materials are high under wet environment operating conditions. The control of rail facility renovation process must be precise. After the rectification is completed, the subway's normal speed must be strictly controlled. In addition, construction preparations, processes and effects are also detailed. This study provides a reference for similar ballast disease treatment in urban rail transit.