水利水电技术（中英文）

针对成贵铁路玉京山隧道穿越巨型溶洞与深厚弃渣回填体系统，分析了弃渣回填体中隧道结构的沉降风险，提出了弃渣回填体中隧道基底处理的方案以及线路跨越的优化结构形式，并通过施工期与长期沉降监测分析了相关方案的可靠性。结果表明，在未经加固的情况下，隧道结构在大规模弃渣回填体中可能会发生高达98 mm的工后沉降，难以满足结构安全以及线路长期运营安全的相关标准。为此，提出了隧道开挖范围及两侧的回填体注浆预加固，以及隧道基底回填体钢管桩注浆加固的基底处理方案，并优化设计了“回填体暗挖隧道衬砌结构防护+洞内连续梁跨越”的组合结构形式。施工期以及长期沉降监测表明，回填体与基底的注浆加固处理能够有效填充空隙并黏结弃渣颗粒，控制回填体的分层沉降。隧道基底沉降变化基本在240 d之后趋于稳定，所有测点的沉降值均能够控制在10 mm之内。然而，各断面左、右测点呈现出较为明显的差异沉降，这说明将轨道设置在洞内连续梁桥上的结构方式在本案例中是合理、必要的。

Aiming at the Yujingshan Tunnel of Chenggui Railway, which passes through a giant cavern and a deep slag backfill system, this paper analyses the settlement risk of the tunnel structure in the slag backfill, puts forward a scheme for the treatment of the tunnel substrate in the slag backfill as well as the optimized structural form of the line crossing, and analyses the reliability of the relevant scheme through the construction period and long-term settlement monitoring. The result show that, without reinforcement, the tunnel structure in the large-scale spoil backfill may experience post-construction settlement of up to 98 mm, which is difficult to meet the relevant criteria for structural safety and long-term operational safety of the line. For this reason, a solution for the tunnel excavation area and the backfill on both sides of the backfill grouting pre-reinforcement, as well as the tunnel base backfill steel pipe pile grouting reinforcement of the substrate treatment is proposed, and the optimised design of the combination of the "backfill backfill excavation lining structural protection + in-cavity continuous beam spanning" form of the structure is proposed. The construction period and long-term settlement monitoring show that the grouting reinforcement treatment of the backfill and the base can effectively fill the voids and bond the discarded slag particles, and control the layered settlement of the backfill. The settlement change of the tunnel base basically stabilised after 240 days, and the settlement values of all the measurement points could be controlled within 10 mm. However, the left and right measurement points of each section show a more obvious difference in settlement, which indicates that the structural method of setting the track on the continuous beam bridge in the tunnel is reasonable and necessary in this case.