盾构隧道纵向裂缝扩展规律及力学性能研究OA
Research on Longitudinal Crack Propagation Pattern and Mechanical Properties of Shield Tunnels
管片结构裂损是地铁盾构隧道的常见病害之一,其中纵向裂缝对隧道结构整体性能影响最大.基于ABAQUS平台建立三环管片结构模型,采用扩展有限元的数值计算方法研究不同位置、长度和深度的纵向裂缝参数和多裂缝工况对管片结构承载能力、横向变形性能的影响以及纵向裂缝的扩展规律.结果表明:当拱顶或拱腰的纵向裂缝长度达到 1/3 环宽及以上时,隧道结构极限承载能力均下降 20%以上、横向椭圆度变形均增加 50%以上,表明预设裂缝的存在会明显减弱盾构隧道力学性能;裂缝位置对结构极限承载能力及裂缝扩展规律的影响较小,对横向变形的影响略高于极限承载能力;不同裂缝长度工况下的结构极限承载能力和横向变形变化幅度低于10%,表明裂缝长度对力学性能的影响不显著;当裂缝深度从 1/15 管片厚度增大到 1/3 时,隧道结构极限承载能力下降 20%以上,表明裂缝深度对管片结构性能的影响最为显著;当拱顶位置有两环或以上存在裂缝时,结构力学性能下降超过 20%,各环裂缝扩展所需的荷载值下降超过 30%,表明拱顶带裂缝环数对结构力学性能和裂缝扩展规律有显著影响.研究综合分析了各纵向裂缝参数并考虑了多裂缝情况,可为地铁隧道运营状态评估提供参考.
The structural damage of segmental linings is one of the common defects in subway shield tunnels,with longitudinal cracks having the most significant impact on the overall performance of the tunnel structure.A three-ring segmental structure model was established using ABAQUS,and the extended finite element numerical calculation method was employed to investigate the effects of different parameters such as location,length,and depth of longitudinal cracks,as well as multiple crack conditions on the bearing capacity,lateral deformation performance,and the propagation pattern of longitudinal cracks.The results indicated that when the longitudinal cracks at the vault or haunch reach 1/3 of ring width or more,the ultimate bearing capacity of the tunnel structure dropped by more than 20%and the lateral elliptical deformation increased by more than 50%,indicating that the presence of pre-set cracks significantly weakened the mechanical properties of the shield tunnel.The influence of the crack location on the ultimate bearing capacity and crack propagation pattern of the structure was relatively small,while its influence on lateral deformation was slightly greater than that on the ultimate bearing capacity.The changes in the structure's ultimate bearing capacity and lateral deformation were less than 10%under different crack length conditions,indicating that the crack length had a negligible impact on the mechanical properties.When the crack depth increased from 1/15 of the segment thickness to 1/3,the ultimate bearing capacity of the tunnel structure dropped by more than 20%,indicating that the crack depth had the most significant impact on the performance of the segment structure.When there were two or more rings with cracks at the vault,the mechanical properties of the structure decreased by more than 20%.The load required for the crack propagation of each ring decreased by more than 30%,which indicated that the number of cracked rings at the vault had a significant impact on the mechanical properties and crack propagation pattern of the structure.The research comprehensively analyzes various longitudinal crack parameters and considers multiple crack situations,which can provide reference for the assessment of the operational state of subway tunnels.
施国俊;杨雨冰;刘超;卢明健
华南农业大学水利与土木工程学院,广州 510642华南农业大学水利与土木工程学院,广州 510642广州大学土木工程学院,广州 510006华南农业大学水利与土木工程学院,广州 510642
交通工程
地铁盾构隧道管片纵向裂缝数值模拟裂缝扩展力学性能
subwayshield tunnelsegmentlongitudinal cracknumerical simulationcrack propagationmechanical property
《铁道标准设计》 2026 (2)
154-163,10
国家自然科学基金项目(52178385,52178209)
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