Abstract:With the continuous increase in the number and service time of bridges in China, the field of bridge is paying more and more attention to displacement monitoring of special structural bridge such as bowstring arch bridge. Based on machine vision methods an arch displacement monitoring scheme is proposed by setting the target at a specific location on the arch and setting the camera at the foot of the arch at both ends. And then taking Youdun Port Bridge in S#@ Highway as an example, the method is experimentally validated. The results indicate that the method can simultaneously achieve sub-millimeter level displacement accuracy, and day and night dynamic monitoring requirements. The arch displacement monitoring of Youdun Port Bridge is achieved. The test results are reliable, which can provide some reference for arch displacement monitoring schemes of similar bowstring arch bridges.