Layout and Assembly Selection Algorithm for Standard Ring+Turning Ring Shield Tunnel Segments

Objective To address the challenges associated with the manual layout and point selection of S+T (standard rings+turning rings (double-sided wedges)) in shield tunnel segments, including high subjectivity, complex calculations, and heavy repetitive workload, a research is carried out focusing on algorithm development to resolve practical engineering issues. Method An automatic layout, assembly selection, prediction algorithm and software are developed for S+T in tunnel segments. Referring to mature construction experience, segment layout plan is calculated based on tunnel alignment and segment turning angles, and segment layout calculation automation is achieved. The calculation and decision-making methods of S+T segment types are proposed with comprehensive consideration of tunnel alignment, shield tail clearance, hydraulic cylinder stroke, and shield machine trends, enabling the automatic selection and assembly of segment points. Furthermore, by establishing a relationship between shield posture changes and variations in shield tail clearance and cylinder stroke, the algorithm can predict the S+T assembly points and segment types for the two future rings. Result & Conclusion The research results are successfully applied to Guangzhou Metro Line 12, significantly improving the efficiency of on-site S+T layout and selection, reducing labor costs, and optimizing the shield tunnel construction process.