Abstract:

Shenyingxian tunnel, which is located in Shenjiamen urban area in Zhoushan city, is 1230m long. The north and south portal sections of Shenyingxian tunnel are located in fullyweathered to heavilyweathered cohesive soil ground containing gravels. The treatment of the portal sections of Shenyingxian tunnel, including small duct reinforcement, umbrella arch reinforcement and grouting reinforcement, is presented in the paper.