| 摘要 |
PURPOSE:To prevent an accident from occurring by providing a preliminary fine earthquake motion sensor and a main motion sensor on or nearby a bridge, and also providing a signal, plural variable indicators, and a speed indicator in the arrival direction of vehicles from in front of the bridge. CONSTITUTION:The signal 5 illuminates in blue normally unless there is abnormality and the indicators 7 and 8 indicate the maximum speed (e.g. 50km/h) of the road. If the preliminary fine motion P wave of an earthquake is sensed in this state, the P wave sensor 3a sends out a sense signal to controller 4. Consequently, the controller 4 makes a specific display on the display device 20 and outputs a control signal 10 through a speed detector S to control the indicators 7 and 8, thereby changing the speed indication of the indicator 7 to, for example, 20km/h and the speed indication of the indicator 8 to, for example, 30km/h. Then when main motion is sensed by the sensor 3b and its intensity exceeds a specific value, the signal 5 is turned from blue to red to force vehicles which travels toward the bridge to stop in front of the bridge. Then all the indications and the display of the display device 20 are blinked through the controller 4 to prevent an accident from occurring.
|
