This paper presents an assessment of the influence of the lagging distance between two horizontal tunnel faces of the side-by-side twin tunnels on the responses of the adjacent existing single pile by a series of thre...This paper presents an assessment of the influence of the lagging distance between two horizontal tunnel faces of the side-by-side twin tunnels on the responses of the adjacent existing single pile by a series of three-dimensional numerical analyses.Two different relative positions between the pile tip and the tunnel are considered to cover the short and long pile behaviors.The responses of the existing pile in terms of pile head settlement,axial force,lateral movement and bending moment are considered and discussed.The numerical results indicate that the lagging distance between twin tunnel faces significantly affects not only the soil movements but also the responses of the existing single pile.The critical case that produces unsatisfactory pile responses due to twin tunneling is when the lagging distance between the second tunnel and the preceding tunnel equals to the shield length.It is recommended that the lagging distance be not less than three times of shield length when the two tunnels need to be concurrently excavated.展开更多
基金supports from King Mongkut’s University of Technology Thonburi(KMUTT),National Research Council of Thailand(NRCT)(Grant No.NRCT5-RSA63006)the Thailand Science Research and Innovation(TSRI)Basic Research Fund:Fiscal year 2023(project No.FRB660073/0164)(Advanced and Sustainable Construction Towards Thailand 4.0)+1 种基金supported by King Mongkut’s University of Technology North Bangkok and National Science,Research and Innovation Fund(NSRF)(Grant No.KMUTNB-FF-65-38)acknowledges the Thailand Science Research and Innovation Fund Chulalongkorn University(Grant No.BCG66210016).
文摘This paper presents an assessment of the influence of the lagging distance between two horizontal tunnel faces of the side-by-side twin tunnels on the responses of the adjacent existing single pile by a series of three-dimensional numerical analyses.Two different relative positions between the pile tip and the tunnel are considered to cover the short and long pile behaviors.The responses of the existing pile in terms of pile head settlement,axial force,lateral movement and bending moment are considered and discussed.The numerical results indicate that the lagging distance between twin tunnel faces significantly affects not only the soil movements but also the responses of the existing single pile.The critical case that produces unsatisfactory pile responses due to twin tunneling is when the lagging distance between the second tunnel and the preceding tunnel equals to the shield length.It is recommended that the lagging distance be not less than three times of shield length when the two tunnels need to be concurrently excavated.
