Design and construction example of inadequate embedded depth of retaining piles in ventilation tower basement excavation of underwater tunnel

The ventilation tower basement excavation of Haicang Tunnel in Huli District of Xiamen City is taken as an example in this article. Owing to design alteration, the analysis of inadequate embedded depth of retaining piles is executed. Result reveals that measures of shotcrete-bolt support system, steal arch system and divisional digging method can successfully ensure the safety of the changed excavation structure. Thoughts and consideration of the calculating method of this design change is described in the end, which may be helpful to familiar constructions.