METHOD FOR CORRECTING LONG-TERM DRIFT AND CREEP PHENOMENON OF BOLT SENSOR IN EARTHQUAKE-PRONE AREA

摘要

PROBLEM TO BE SOLVED: To appropriately display a change in bolt pretension especially in an earthquake and correct a signal drift.SOLUTION: A method according to the present invention periodically performs, at prescribed measurement period times, the steps of: detecting a most recent bolt sensor signal; verifying whether the bolt sensor signal is within a detection range; outputting an alarm signal and stopping an evaluation routine when there is no bolt sensor signal within the detection range; storing the detected bolt sensor signal in a storage device and continuing the evaluation routine when the bolt sensor signal is within the detection range; verifying whether or not the earthquake occurs; comparing the detected bolt sensor signal with the previously stored bolt sensor signal; and determining whether or not the detected bolt sensor signal is different from the previously-stored bolt sensor signal greatly more than a prescribed threshold and outputting an alarm signal when the difference exceeds the threshold.SELECTED DRAWING: Figure 1