Objective Compared with shield tunnels using bolted connections, shield tunnels with new-type joints exhibit several advantages, including greater overall rigidity of segments, higher bending and shear resistance, low probability of water leakage and high degree of mechanized construction. However, researches on the dimensional design, construction equipment, and construction control of this type of shield tunnel are still in their preliminary stage.

Method Taking the Jiangxinzhou Shield Tunnel Project in Nanjing as the enginee-ring background, and with reference to the control calculation method for part assembly accuracy in the mechanical discipline, a tolerance accumulation analysis model for shield tunnel segment assembly with quick joints in this project is established. Based on this model, a sensitivity analysis is conducted on the component characteristics, and the impact of manufacturing to-lerances of different components in the new-type joint segments on segment assembly is also analyzed. From the perspective of assembly reliability, an assembly method capable of effectively controlling errors is proposed. Finally, tolerance of the segment components for this project is designed.

Result and Conclusion Among the component feature tolerances, the segment end face tolerance is the most important tolerance control feature, and the segment end face flatness tolerance is a key factor affecting the assembly reliability. When the segment end face flatness tolerance is controlled within ± 0.1mm/m, the segment assembly reliability can meet the engineering requirements.