Abstract:

For the high risks of shield arrival in complex construction environment of the first terrace of Yangtze River, the method of combining vertical ground freezing and cement improvement, i. e. high pressure rotary jet pile and glass fiber reinforced pile, is taken to improve soil on shield ends in Wangjiadun East to Xinhua road section of Metro line 7 in Wuhan after solution comparison and optimization. Freezing effect is checked, and shield arrival process,main construction parameters in receiving stage, the construction scheme of two-time shield arrival are summarized to elaborate the application of combined schemes in shield arrival construction. It is proved that the combined solution is technically feasible, and it can effectively avoid the risk of water and sand gushing without surface traffic untwining and pipeline relocation when shield tunneling reaches the arrival area, which can save nearly 5 million RMB and bring significant comprehensive benefits. It is hoped to provide better reference for the similar project in the future.

Key words: shield arrival, scheme optimization, combination improvement, cement system, ground freezing, steel sleeve