高速铁路无砟轨道支承层原位快速更换技术

In-situ Fast Replacement Technology for Ballastless Track Supporting Layer of High Speed Railway

高速铁路无砟轨道混凝土支承层属隐蔽结构,位于无砟轨道结构底部。在长期运营中,个别支承层结构会出现上拱斜裂、严重粉化等伤损,需及时进行更换处理。以"天窗点内施工、对轨道结构扰动小、施工安全高效"为原则,提出基于绳锯切割的无砟轨道支承层原位快速更换技术。首先通过绳锯切割将待更换部位支承层切割成块状单元,然后以顶推与抽拉相结合的形式将伤损混凝土单元横向移出,最后原位浇筑自流平、高早强的聚合物混凝土对支承层进行快速恢复。现场应用表明,该技术解决了以往采用钢垫梁临时过渡技术处理支承层伤损时需要锯轨和大型轨道装备配合的问题,具有施工可控性强、整治周期短、限速天窗占用少、对轨道结构扰动小、安全风险低的优点,可有效解决运营期无砟轨道支承层伤损更换难题。

The concrete supporting layer of ballastless track of high speed railways,as a concealed structure,is located at the bottom of the ballastless track structure.During the long-term operation,some supporting layer structures may be damaged,such as upwarp and oblique crack,serious pulverization,etc.,and need to be replaced in time.Following the principle of“construction within the maintenance window,small disturbance to the track structure,safe and efficient construction”,this paper proposes the in-situ fast replacement technology for ballastless track supporting layer based on wire saw cutting.Firstly,the supporting layer of the part to be replaced is cut into block-shaped units by a wire saw,then the damaged concrete unit is transversely removed by jacking and pulling,and finally the supporting layer is quickly recovered by in-situ pouring of self-leveling and high-early-strength polymer concrete.The on-site application shows that this technology solves the problem of coordination between rail sawing and large track equipment when the temporary transition technology of steel bearing beam was used in the past to treat the damage of the supporting layer,and has the advantages of strong construction controllability,short remediation cycle,less occupation of speed limiting window,small disturbance to track structure and reduced safety risk,which can effectively solve the problem of replacing the ballastless track supporting layer of lines in operation.