京张高铁清华园隧道轨下结构预制拼装技术

Fully Prefabricated Assembling Technology of Tsinghuayuan Tunnel in Beijing-Zhangjiakou High-speed Railway

京张高铁清华园隧道是国内第一座全预制拼装的高铁隧道,其支护结构、轨下结构和附属结构均采用工厂化预制,并研发了拼装机器人,实现了隧道全预制拼装施工。采用数值模拟方法,分析轨下结构的强度、变形和稳定性,并根据预制拼装施工工艺的要求,提出一种3块式轨下预制结构,在满足稳定性要求的前提下,利用轨下空间为隧道提供通风和救援通道。轨下结构与盾构管片的连接是全预制拼装结构的关键技术,通过阐述轨下结构的注浆工艺及其施工要点,确保轨下结构与盾构管片受力均匀,可为今后类似工程的建设提供借鉴。

Tsinghuayuan Tunnel of Beijing-Zhangjiakou High-speed Railway is the first fully prefabricated high-speed railway tunnel in China. The supporting structure, subrail structure, and subsidiary structure of Tsinghuayuan Tunnel are all prefabricated in the factory. The strength, deformation and stability of subrail structure are analyzed by numerical simulation method;a kind of three-block type of subrail prefabricated structure is put forward according to prefabricated assembling technology;and the subrail space is used to ventilate and rescue under the stability condition. The connection between subrail structure and shield segment is the key to fully-prefabricated assembling technology. By introducing the grouting technology and construction keys of subrail structure, the stress on subrail structure and shield segment can be balanced. The results can provide reference for similar projects in the future.