为探索预制综合管廊盾架一体化施工关键技术，提升预制综合管廊机械化施工水平及效率，以雄安新区某综合管廊项目为依托，对U盾架管机开挖、推进、调向等关键技术进行研究。通过构建U盾架管机推进受力模型，探索掌子面预留核心土对推进阻力的影响，得出不同断面管节所需的管节密封压紧力对应的核心土欠挖量，验证U盾架管机采用主顶油缸压紧管节密封的可行性；采用插刀、推板超欠挖进行辅助纠偏，联合主顶油缸、铰接油缸分组协同控制，将掘进姿态控制在±20 mm以内； 针对U盾架管机平、纵断面折线转弯工况，采用可调节环宽的楔形过渡桥施工技术，实现最大7.7°水平折线转弯、70‰纵坡折线转弯；同时，对U盾部分与架管机部分在掘进、调向、管节安装过程中的协同施工技术进行研究。现场应用试验表明： U盾架管机施工可以满足预制综合管廊沟槽开挖、设备推进、掘进调向、管节安装等工序的一体化施工需求。
Primary technologies such
as excavation, propulsion, and direction adjustment of the U-shaped shield pipe erecting machine are examined in a utility tunnel
project in Xiong′an. The objective is to explore the
key technology of integrated shield excavation-pipe
erection construction of prefabricated utility tunnels and improve the
mechanized construction level and efficiency of prefabricated utility tunnels.
A propulsion force model of the U-shaped shield pipe
erecting machine is constructed to analyze the influence of the reserved core
soil on improving propulsion resistance. The under-xcavated
volume of the core soil corresponding to the sealing compressive force required
by different sections of pipe is obtained from an established mathematical
model to validate the feasibility of using the propulsion hydraulic cylinder to
compress the sealing of the pipe joint in the U-shaped
shield pipe erecting machine. Assisted by the insert cutters and propulsion
plates for over- and under-excavation,
the excavation attitude of the machine is controlled within ±20 mm under the coordinated control of jacking hydraulic cylinders
and articulated hydraulic cylinders. Under horizontal and vertical broken-line turning conditions, a wedge-shaped
transition bridge with adjustable ring width can realize 7.7° horizontal broken-line turning and 70‰ longitudinal broken-line turning of the U-shaped shield pipe erecting machine. Finally, the cooperative
construction technology of the U-shaped shield and pipe
erecting machine during excavation, direction adjustment, and pipe installation
is explored. The U-shaped shield pipe erecting machine
exhibits feasibility in excavation, propulsion, direction adjustment, and pipe
installation of the prefabricated utility tunnels.
