ABSTRACT
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Structural durability diseases of sound barrier erected on urban rapid viaduct have become more obvious with the disturbance effect of aerodynamic load induced by running vehicles. Primary reason lies in no enough consideration of vehicle-induced aerodynamic load (VIAL) action on sound barrier and its effect in the process of structural design, especially the absence of anti-fatigue design under VIAL. For sound barrier in service on urban rapid viaduct, under the action of VIAL, surface wind pressure on screen body and its vibration response can be easily collected by on-site wind pressure and acceleration acquisition system. Recent research demonstrates that VIAL on sound barrier depends on vehicle flow running characteristics directly, but there is almost no reference to introduce how to monitor the vehicle shape, speed and vehicle-barrier separation distance accurately. However, vehicle flow running characteristics is vital for research on sound barrier fatigue under the action of VIAL. In this paper, photogrammetry and image analysis has been brought into study of VIAL on sound barrier through an innovation monitoring method, that is to say, on-site multi-camera system is arranged to collect data of vehicle flow running characteristics, and wind pressure and acceleration acquisition system is also used at the same time. Specifically, running vehicles passed through the road test zone monitored with multi-camera system, and a serial of works were carried out in order to obtain data of vehicle shape, speed, and position, including camera calibration, stereo matching, three-dimensional reconstruction and image recognition. And then, the numerical relationship among vehicle shape, speed, vehicle-barrier separation distance and VIAL on screen body and its vibration response is established with simultaneous measurement of screen surface wind pressure and acceleration data. In addition, according to some field test cases, results from numerical simulation analysis based on Computational Fluid Dynamics well match with field test data. The proposal monitoring method integrated with photogrammetry and image analysis is significant useful for fitting calculation formula of VIAL on sound barrier, further research combined with traffic flow prediction theory can be suitable for establishing the fatigue load spectrum of sound barrier under action of VIAL. Dense point clouds of four typical vehicles. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315207681/cd556cd4-4dcf-4efe-8e29-56fc67b8bfbd/content/fig75_1.jpg"/>
