西安地铁盾构下穿古城墙沉降分析及加固效果

发布时间：2019-05-24 00:02

【摘要】：为研究双线盾构下穿过程诱发地表沉降的规律及上部古城墙的变形特征,依托地铁4号线区间隧道下穿和平门古城墙工程,通过数值模拟和现场测试手段对沉降及加固效果进行分析。结果表明:在袖阀管注浆加固及门洞钢拱架支护等作用下,城墙地基区域地表沉降值减小4mm,城墙结构沉降减小约2.2mm,避免了地基局部隆起过大和倾斜率超限;城墙地基区域加固工况下地表横向沉降曲线为宽而浅的单峰沉降槽,未加固工况下表现为窄而深的双峰沉降槽;左、右线隧道施工存在相互影响,且变形稳定后右线隧道地表沉降峰值大于左线。现场实测与数值计算的结果吻合良好,分析方法和研究结果可为日后黄土地区类似的盾构穿越工程提供有益的参考。
[Abstract]:In order to study the law of surface subsidence induced by double-line shield tunneling and the deformation characteristics of the upper ancient city wall, relying on the subway line 4 interval tunnel through the Haimen ancient city wall project, The settlement and reinforcement effect are analyzed by numerical simulation and field test. The results show that under the action of sleeve valve pipe grouting reinforcement and portal steel arch support, the surface settlement value of the wall foundation area is reduced by 4 mm, and the wall structure settlement is reduced by about 2.2 mm, which avoids the excessive local uplift and overrun slope of the foundation. Under the condition of strengthening the wall foundation, the lateral settlement curve of the surface is a wide and shallow single peak settlement trough, and under the unreinforced condition, it shows a narrow and deep bimodal subsidence trough. The construction of left and right line tunnel has mutual influence, and the peak value of surface settlement of right line tunnel is larger than that of left line after deformation stability. The results of field measurement and numerical calculation are in good agreement with each other. The analysis method and research results can provide useful reference for similar shield crossing projects in loess area in the future.
【作者单位】：中铁第一勘察设计院集团有限公司;长安大学公路学院;中铁一局集团有限公司;
【基金】：陕西省科技厅社会发展科技攻关项目(2016SF-412) 中央高校基本科研业务费专项资金资助项目(310821172004,310821165011,310821153312)
【分类号】：U231.3;U455.43

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