Abstract: The mechanical properties of immersed tunnel joints are the key to their safe operation. By analyzing the monitoring data of joint settlement of Yongjiang immersed tube tunnel in Ningbo for 23 years operation, the relationship between uneven settlement of immersed tube tunnel in soft soil foundation and joint deformation of immersed tube tunnel is found, and the laws and reasons of uneven settlement are analyzed and discussed. The stress model for GINA waterstop is established, the stress of GINA waterstop caused by joint deformation is calculated, and the safety of joint waterstop is checked. Finally, the safety assessment method for the structures by using the settlement monitoring data of the tunnel through the forced displacement method during its operation is put forward.