This study presents a case history of a tunnel lining with an insufficient thickness.The effect of the defects resulting from the insuf-ficient thickness of the secondary lining and their locations on the internal for...This study presents a case history of a tunnel lining with an insufficient thickness.The effect of the defects resulting from the insuf-ficient thickness of the secondary lining and their locations on the internal forces are discussed based on numerical analysis.The results show that defects increase the number of inflection points in the defect region.The increased maximum bending moment is located on the air side of the secondary lining around the defect region.The defects near the crown of the secondary lining have the most significant influence on the internal forces of the primary and secondary linings,while the defects near the sidewall of the secondary lining have a limited influence on the internal forces of the lining.A remediation measure consisting of the installation of a tertiary lining is proposed and its efficiency is analyzed.The tertiary lining significantly reduces the bending moment of the secondary lining and the axial force of the primary lining.The effect of the thickness and location of the tertiary lining on the tunnel performance is discussed.展开更多
基金sponsored by the National Natural Science Foundation of China(Grant Nos.51868017,52078337)the Hainan Provincial Natural Science Foundation of China(Grant No.2019RC079)the Natural Science Foundation of Tianjin,China(Grant No.20JCQNJC01080).
文摘This study presents a case history of a tunnel lining with an insufficient thickness.The effect of the defects resulting from the insuf-ficient thickness of the secondary lining and their locations on the internal forces are discussed based on numerical analysis.The results show that defects increase the number of inflection points in the defect region.The increased maximum bending moment is located on the air side of the secondary lining around the defect region.The defects near the crown of the secondary lining have the most significant influence on the internal forces of the primary and secondary linings,while the defects near the sidewall of the secondary lining have a limited influence on the internal forces of the lining.A remediation measure consisting of the installation of a tertiary lining is proposed and its efficiency is analyzed.The tertiary lining significantly reduces the bending moment of the secondary lining and the axial force of the primary lining.The effect of the thickness and location of the tertiary lining on the tunnel performance is discussed.