曲线盾构隧道掘进地表沉降计算模型研究

盾构隧道掘进过程中产生的地层损失和施工荷载是引起地表沉降的主要因素，曲线盾构隧道的非对称性使得掘进引起地表沉降规律更加复杂。基于直线盾构隧道掘进引起地表沉降的研究成果，考虑实际工程中隧道会由于自重而沉降到土体边界底部和曲线盾构隧道地层损失的非对称特征，建立了曲线盾构隧道掘进引起地表沉降的地层损失模型，同时将建立的模型与已有曲线隧道地层损失模型进行对比研究。结果表明:本文建立的地层损失模型引起的地表沉降变形值更大，受转弯半径的大小影响，当隧道转弯半径大于1000米后，曲线隧道与直线隧道地层损失引起地表沉降值变化较小，而当隧道转弯半径小于300米时，此时地表沉降值对隧道转弯半径的敏感性较高，文章建立的计算模型可以很好的体现出小转弯半径隧道引起的地表沉降值的影响程度更大；通过将两种不同地层损失模型引起的地表变形与实际工程进行比较分析，验证了文章建立的计算模型与实际数据更接近，误差更小，显示该模型能够较好地反映实际情况，研究成果为曲线盾构隧道掘进引起地表沉降分析和预测提供参考。

Study on Theoretical Model of Surface Settlement Caused by Curved Shield Tunnelling

The ground loss and construction load are the main factors causing surface settlement during curved shield tunneling. The asymmetry of curved shield tunneling makes the law of surface settlement caused by tunneling more complicated. Based on the existing researches of the ground surface settlement caused by linear shield tunneling, a ground loss model is established for calculating the ground surface settlement caused by the tunnel will settle to the bottom of the soil boundary due to self-weight in the actual project and shield tunneling with considering the asymmetric characteristics. And The developed model is compared with the existing ground loss model of curved tunnel. The results show that the surface settlement deformation caused by the stratigraphic loss model established in this paper is larger, and is affected by the size of the turning radius, when the tunnel turning radius is greater than 1000 m, the surface settlement value caused by ground loss in curved and straight tunnels changes less, while when the tunnel turning radius is less than 300 m, the sensitivity of the surface settlement value to the tunnel turning radius is higher at this time, and the calculation model in the article can well By comparing the surface deformation caused by the two different ground loss models with the actual project, it is verified that the model in the article is closer to the actual data with less error. The calculated results of the model are in good agreement with the actual data, indicating that the model can reflect the actual situation well. The research results can provide reference for the analysis and prediction of surface settlement caused by curved shield tunneling.