Research On The Mechanism Of Bridge Crack Monitoring Based On Smart Film

In recent years, a large number of bridge collapses has been occurred in China. Itcaused not only loss of life, but also the direct or indirect economic loss is morealarming. Because the design and construction processes of bridges are very complex,and the existing technology of building the box girder is not mature enough, so thereare some potential security problems after the construction of bridges has beencompleted. In addition, because of environmental erosion, material aging andlong-term effects, the fatigue effect and mutation effects, such disasters factors willinevitably cause the structures and systems damage to accumulation and resistance toattenuation in the bridge operation period, any damage caused by the factors is greatestthreat to the safety of bridge operation. Therefore, the bridge structural healthmonitoring has become forefront of research on structure of the major bridge in theworld.Most bridges on duty and bridges under construction are concrete bridge in China,its failure and aging on structural performance are due to the initiation anddevelopment of crack, so the online and long-term bridge crack monitoring is a veryimportant practical value in the assessment of status on bridge health. However, as thelarge-scale properties of the bridge structure, only that the sensor completely coveredthe key areas throughout the bridge structure to be able to effectively monitor the statuson bridge crack. If using traditional sensor technology, not only costs too much andspends more workload, but it is not convenient, so it is not accepted. Therefore, thecurrent crack monitoring in the bridge structure needs to be improved and developed.Because the research on crack width monitoring is the core point of bridge crackmonitoring, so the research on the crack width monitoring is necessary, it based on themonitoring technology of Smart Film has been applid in the bridge.To be aimed at bridge crack is related to the safety of bridge, in this paper, SmartFilm for crack monitoring is conducted a study on its mechanism of crack monitoring,it has been achieved in the bridge. First, suppose the relationship between crack widthand residual elongation, based on shear-lag, to establish a Theoretical model foranalysis. Then, using new indicator to produce some different smart wires, conduct theexperiment for simulate the situation of the actual monitoring on crack width, to getthe data on the relationship between crack width and residual elongation andcomparative result of Shear-Lag model to verify their validity, for establish a new monitoring indicators of cracks monitoring system on smart film. Finally, verify theeffect of the monitoring system with result of crack monitoring for the actual bridge.This paper is expected to promote the research on the mechanism of crackmonitoring on Smart Film depth and perfect, provide the basis on the real-time, onlineand long-distance monitoring for safety of bridge, and then take positive measures toprotect the safe operation on bridge.