Abstract:

To realize synchronous implementation of tunnel boring machine(TBM) excavation and construction material transportation during invert arch castinplace construction, a design scheme of plane invert arch with bearing platform is proposed through analysis and comparison. Additionally, a synchronous castinplace lining trolley for TBM tunnel invert arch integrating climbing rail, Ushaped main beam, segmented support, stepping shift, and invert arch formwork is developed. Finally, a series of synchronous castinplace techniques for invert arch are developed, which includes track demolition, tunnel bottom muck cleaning, steel bar binding, invert arch casting and maintenance, and track installation. The scheme, trolley, and techniques mentioned have been successfully applied in Xianglushan tunnel of Central Yunnan water diversion project. The castinplace lining of invert arch did not affect the normal construction of TBM. The operation cycle time of 24 m castinplace invert arch in a single warehouse was 44 h, and the construction progress reached 200 m a month, realizing synchronous and efficient operation of invert arch castinplace construction and TBM tunneling, which is worth popularizing.

Key words: invert arch lining, synchronous castinplace, lining trolley, superlong tunnel, Central Yunnan water diversion project