Convergence monitoring is of great importance to evaluate the tunnel health condition. This paper introduces a real-time convergence monitoring system of shield tunnel with straight joints based on wireless tilt sensors. Wireless tilt sensors have the advantages of real-time monitoring, flexibility and ease of installation, no interruption to tunnel operation and no demand of inter-visibility. A model of calculating horizontal convergence from tunnel inclination for different diameter tunnels is proposed. Optimal sensor measurement positions are adopted to improve the accuracy of the proposed model. For a shield tunnel with six segments, one wireless sensor is installed at the optimal position of 123° with a maximum relative error of 6%. For a large diameter shield tunnel with ten segments, two wireless tilt sensors installed at the optimal positions of 107° and 143° are obtained. The absolute errors of tunnel horizontal convergence for the two sensors scheme are less than 0.33 mm, which shows the high precision of this scheme. The proposed model is verified for tunnels with asymmetric deformation induced by surcharge load. The proposed model has a maximum relative error of 4.5% in layered ground. A field monitoring case of Shanghai metro tunnel proves the applicability of the proposed method.

收敛监测对于评估隧道健康状况非常重要。介绍了一种基于无线倾斜传感器的直缝盾构隧道实时收敛监控系统。无线倾斜传感器具有实时监控，灵活性和易于安装的优点，不会中断隧道操作，也不需要相互可见。提出了一种根据隧道倾角计算不同直径隧道水平收敛性的模型。采用最佳传感器测量位置以提高所提出模型的准确性。对于具有六段的屏蔽隧道，在123°的最佳位置安装了一个无线传感器，最大相对误差为6％。对于具有十段的大直径盾构隧道，获得了两个安装在107°和143°最佳位置的无线倾斜传感器。两个传感器方案的隧道水平收敛绝对误差均小于0.33 mm，说明该方案具有较高的精度。对于超载荷载引起的非对称变形隧道，该模型进行了验证。所提出的模型在分层地面中的最大相对误差为4.5％。上海地铁隧道现场监测实例证明了该方法的适用性。5％在分层地面中。上海地铁隧道现场监测实例证明了该方法的适用性。5％在分层地面中。上海地铁隧道现场监测实例证明了该方法的适用性。