曲线盾构隧道施工稳定性及致险水平研究

发布时间：2019-06-30 20:22

【摘要】：小曲率半径盾构隧道施工稳定性影响因素错综复杂,对不同评价指标的作用规律及致险等级差异显著。以济南厚冲洪积地层为地质条件,基于正交试验建立了5因素4水平6指标的小半径盾构施工稳定性综合评价体系,通过多影响因素的定量分析与定性评价,确定了其敏感性排序及致险水平等级。结果表明:隧道埋深与盾构直径对地层变形具有强烈致险作用,随埋深的增大,地表最大沉降值与沉降槽宽度呈线性递增;隧道曲率半径及千斤顶不平衡推力对曲线盾构地表沉降槽偏移与管片两侧差异变形影响显著,随曲率半径的增大,地表沉降峰值点偏移量与管片两侧变形差呈线性递减,管片最大拉应力呈二次函数递减。研究成果对曲线盾构隧道施工的参数评价及风险防控具有重要指导意义。
[Abstract]:The influencing factors of construction stability of shield tunnel with small curvature radius are complex, and the action law and risk grade of different evaluation indexes are significantly different. Taking Jinan thick alluvial strata as geological conditions, a comprehensive evaluation system of small radius shield construction stability with 5 factors and 4 levels and 6 indexes is established based on orthogonal test. Through the quantitative analysis and qualitative evaluation of multiple influencing factors, the sensitivity ranking and risk level grade are determined. The results show that the buried depth of the tunnel and the diameter of the shield have a strong dangerous effect on the formation deformation. With the increase of the buried depth, the maximum settlement value of the surface and the width of the subsidence trough increase linearly. The curvature radius of the tunnel and the unbalanced thrust of the Jack have a significant effect on the deviation of the curved shield surface subsidence trough and the differential deformation between the two sides of the segment. With the increase of the curvature radius, the deviation of the peak point of the surface settlement and the deformation difference between the two sides of the segment decrease linearly, and the maximum tensile stress of the segment decreases by quadratic function. The research results have important guiding significance for the parameter evaluation and risk prevention and control of curved shield tunnel construction.
【作者单位】：济南轨道交通集团有限公司;山东科技大学土木工程与建筑学院;
【基金】：山东省自然科学基金资助项目(ZR2014EEM029,ZR2014EEQ028) 山东省重点研发计划资助项目(2015GSFI20017) 住房与城乡建设部科学技术资助项目(2016-k4-053)
【分类号】：U455.43

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