Abstract:

In order to overcome the high cost and low efficiency of the conventional data acquisition systems for structure monitoring of long-span bridges, an automatic switching system is proposed for the connection of sensors based on DataTaker collectors. In the proposed system, the conventional direct connection between sensors and collectors is changed into an indirect connection through hubs and controllers, and the automatic switching between the hubs and sensors is implemented via the controllers excited by the digital signals output from the DataTaker collectors. Thus, the data from different sensors are effectively collected. Laboratory tests demonstrate that the proposed system is of high reliability and good stability. Moreover, the application of the system to the stress monitoring of a large-span arch bridge shows that the automatic switching system with good practicability effectively reduces the cost of stress measurement and improves the efficiency of data acquiring, data saving and transmission.

Key words: bridge monitoring, data acquisition system, automatic switching system, sensor, hub, controller, collector