超小净距盾构下穿既有铁路隧道影响分析OA

Based on the ultra-small clear distance shield tunnel project of Nanning Metro Line 4 passing beneath the Chalu Tunnel of the coastal railway,the finite element software midas GTS NX was used to analyze the construction process of the shield tunnel and rail reinforcement works at the intersection.The research results indicate that without reinforcing the ex-isting railway track and tunnel,the maximum surface settlement value is 6.5 mm,the maximum settlement value at the rail is 3.91 mm,and the maximum vertical differential settlement value of the rail structure along the track direction is 2 mm/10 m,and the maximum settlement value of the railway tunnel structure is 4.73 mm,so the deformation values and the lin-ing structure forces meet the requirements.After adopting the treatment measures of"3-5-3 rail fastening reinforcement",the maximum settlement value of the track was significantly reduced(from 2.6 mm to 0.4 mm).The successful implementation of the underpass project demonstrates the rationality and effectiveness of the engineering solution,and the research findings can serve as a reference for similar projects.