高速铁路双块式无砟轨道路基地段结构设计与施工技术研究

为了提高双块式无砟轨道的设计和施工质量,首先对路基地段双块式无砟轨道道床板和支承层的功能定位进行分析,提出连续道床板和分块道床板两种结构设计方案的主要特点和设计要点,并对两种设计方案进行结构受力和配筋计算。然后从抗压强度、结构耐久性、疲劳强度、裂缝控制等要求研究道床板混凝土的强度等级,提出道床板混凝土强度采用C40是足够的,且强度不宜太高。最后结合目前双块式无砟轨道施工和运营经验,提出道床板和支承层在施工过程中应注意的一些问题。

Research on Structure Design and Construction Technology of Bi-Block Ballastless Track for Subgrade Sections of High-Speed Railway

In order to improve project quality of structure design and construction technology of Bi-Block ballastless track,the functions of track slab and supporting layer for subgrade sections are analyzed,and two alternative design schemes are presented. The differences between the two lie largely in that the track slabs are continuous or un-continuous units. The main features and design elements of the two are also put forward,and structure stress analysis and steel bar solutions related to the two schemes are carried out respectively. The concrete strength grade of track slab is studied in terms of compressive strength,structure durability,fatigue strength and crack control requirements. The results show that C40 concrete for track slab is adequate in strength and the strength of concrete should not be much too high. Moreover,some problems of track slab and the supporting layer that may happen during construction are addressed based on the experiences in construction and operation of the current bi-block ballastless track.