Similar Triangle Method in Highway Tunnel Vault Subsidence Monitoring

Traditional manual testing can no longer meet the needs of the engineering monitoring because of uncertain dangers in the process of the construction and operation, such as deformation of surrounding rocks, convergence of the surrounding, overlarge stress, vault subsidence and soil landslide. The automatic monitoring system of highway tunnel vault subsidence based on the similar triangle method can not only collect real-time data and analyze the subsidence amount of tunnel vault, but also can automatically alarm by sound and light alarm, when the tunnel vault subsidence exceeds the set value. The experiment results show that the monitoring system has overcome the shortcomings of traditional manual detection, such as low precision, high risk, limited measurement conditions, poor real-time performance and slow warning. The monitoring system is simple and practical, and it's results are accurate. The achievements can be applied to the automatic monitoring of the arch structure.