盾构隧道穿越高速铁路会对铁路轨道、路基等构筑物沉降产生影响，严重影响高速铁路的运行。为研究贵阳地区盾构隧道下穿高速铁路对框架箱涵、路基和高铁轨道沉降规律的影响和适用于贵阳地区的盾构施工参数，依托贵阳轨道交通3号线，建立土层-框架涵-道床-轨道的模型，分析在石灰岩中盾构施工对框架涵、既有高铁轨道和路基的沉降规律，并且对盾构施工参数进行优化。结果表明：盾构隧道下穿框架涵，框架涵的横向沉降和纵向沉降呈“W”形，从沉降曲线整体来看，沉降曲线呈“双蝶状”曲线，掘进过程中框架涵沉降峰值为1.805 mm；盾构机穿越路基和隧道贯通时会引起路基沉降的突变，随着开挖的进行，路基沉降会产生沉降峰值的转移，路基沉降峰值为1.753 mm；高铁轨道沉降曲线随着开挖呈现单个峰值且沉降槽的宽度与框架桥宽度大致相同，轨道沉降的峰值为1.41 mm；通过分析8种盾构掘进压力和8种注浆压力对路基沉降的影响规律可知，注浆压力较掘进压力对沉降具有较好的控制效果，并且随着注浆压力的提升，路基表面沉降峰值在减小，注浆压力为800 kPa时，路基表面沉降峰值为1.355 mm，变形率最大为20.7%，经分析，将盾构机的注浆压力和掘进压力分别设置为400 kPa和100 kPa。

The construction of the shield tunnel for the high-speed railway will impact the settlement of railway tracks, roadbeds, and other structures, potentially affecting the railway's operation. In order to study the influence of shield tunnel underneath the high-speed railroad in Guiyang area on the settlement pattern of frame box culvert, roadbed and high-speed railway track and the shield construction parameters suitable for Guiyang area, relying on Guiyang Rail Transit Line 3, the model of soil layer-frame culvert-roadbed-track was established to analyze the settlement law of shield construction in limestone on frame culvert, existing high-speed railroad track and roadbed, and to optimize the parameters of shield construction. The results indicate that the settlement of the frame culvert exhibits a "W" shaped transverse and longitudinal settlement pattern, with a peak settlement value of 1.805 mm during the tunneling process. The shield machine's crossing causes a sudden change in subgrade settlement, with the peak value reaching 1.753 mm. High-speed rail track settlement shows a single peak with excavation, with a peak value of 1.41 mm. Analysis of eight types of shield tunneling pressure and grouting pressure reveals that grouting pressure has a better control effect on settlement than excavation pressure. Increasing grouting pressure leads to a decrease in the peak value of subgrade surface settlement, with the peak value reaching 1.355 mm at 800 kPa grouting pressure. The maximum deformation rate is 20.7%, with grouting pressure set at 800 kPa and tunneling pressure at 100 kPa for the shield machine.