理论研究 2024年 第53卷 第21期

DOI: 10. 7672 / sgjs2024210078

隧道施工引起的既有地铁线变形控制研究

牛自强

作者简介:

牛自强,高级工程师,E⁃mail:16609317888@ 163. com

作者单位:

中铁十二局集团有限公司,山西太原 030024

摘要:

依托某市新建地铁 3 号线盾构隧道工程,通过数值模拟计算,基于土舱压力和注浆压力,研究新建盾构隧道下穿施工对既有地铁 5 号线隧道结构变形的影响,并提出变形控制措施。研究结果表明,当地铁 3 号线隧道左线盾构机到达既有地铁隧道正下方区域和右线盾构机掘进完成时,随着压力比的增大,既有地铁 5 号线隧道拱顶竖向位移分别逐渐增大和逐渐减小,而随着注浆压力的增大,既有地铁 5 号线隧道拱顶竖向位移均基本减小。宜将土舱压力控制为 1. 0 —— 1. 2 倍静止土压力,注浆压力控制为 0. 64 —— 1. 00MPa.从施工成本和加固效果角度考虑,宜将二次深孔注浆作为合理的加固方式。

English:

Based on the shield tunnel project of a newly built Subway Line 3 in a certain city, numericalsimulation calculations were conducted to study the impact of the construction of the new shield tunnelunderpass on the structural deformation of the existing Subway Line 5 tunnel, based on soil chamberpressure and grouting pressure, and deformation control measures were proposed. The research resultsshow that when the left line shield machine of Subway Line 3 tunnel reaches the area directly below theexisting subway tunnel and the right line shield machine completes excavation, the vertical displacementof the existing Subway Line 5 tunnel arch gradually in creases and decreases with the increase of pressureratios, however,with the increase of grouting pressure, the vertical displacement of the existing SubwayLine 5 tunnel arch is basically reduced. It is advisable to control the soil chamber pressure at 1. 0 —— 1. 2times the static soil pressure, and the grouting pressure at 0. 64 —— 1. 00MPa. From the perspective ofconstruction cost and reinforcement effect, the secondary deep hole grouting reinforcement method shouldbe considered as a reasonable reinforcement method.