Internal forces of DOT shield-driven tunnel lining

An analytical solution for the calculation of internal forces of a jointed segmental precast DOT（Double-O-Tube） lining based on the unbalanced forces transition method was presented.With the calculation of a practical project,the numerical simulation method and some data from field measurements were both used to compare and analyze the internal forces of DOT lining.It was shown that the internal forces obtained by analytical solution were the largest,the internal forces obtained by numerical simulation were the smallest and the measured values were in the middle.However,the distributions of internal forces obtained by three different methods well agreed with each other,which demonstrated that the analytical solution was reasonable and reliable.The sensitivities of the design parameters to the distribution of internal forces of DOT lining structure were analyzed,and it was shown that the shoulder ground pressure played an important role to the distribution of internal forces and should not be neglected and the soil resistance coefficient can be chosen between 2500 kN/ m3 and 6500 kN/ m3 in order to activate the soil resistance fully.With respect to the reasonable design and optimization of the cross-section as well as the consideration of the safety factors,the opening angle α should be chosen between30 60 degrees.