Research On Bridge Test Model For Damage Identification Of Cable-stayed Cable Based On The Deflection Monitoring

With the increasing use of the cable-stayed bridge, the degree of damage of the cable-stayed bridge is caused by cumulative damage under the natural condition and accidents,which will become more and more serious.The damage problem of cable is more outstanding, which directly leads to the change of cable tension and deflection of beam, thereby affecting the safe operation of the cable-stayed bridge. In recent years, although many scholars have conducted the research on the test model of structural damage, but the cable damage caused by deflection change is little research. As mentioned above, the paper carries out the research on the test model of cable stayed bridge. For the latter part of the cable-stayed model test study, and then verify the results of theoretical analysis.First of all, this paper refers to the characteristics of the general cable-stayed bridge and two examples of cable stayed bridge. A popular virtual cable-stayed bridge is designed. According to the similarity theory, the test model of virtual cable stayed bridge is designed.The utilize the Midas civil to establish space finite element model, and the calculation is done respectively, and the comparison of the two calculation results to determine the test model is reasonable.Secondly, the model was as the benchmark model, when different train loads and no cable damage, and the impact of them on the changes of cable tension and girder deflection.Finally,the cable damage is simulated through reducing the cable area by 11.1%, 33.3%, 55.6%, 77.8%.Analyzing the deflec cable force change tion change and cable force change induced by the different degree of single cable damage or double cables damage.And comparing defection change and cable force change under the action of different train load and no cable damage.Through calculation and analysis, it is found that the cable tension and the deflection of the anchorag point are changed with the position of the train load.When the cable damage, the cable tension reduces, The deflection of the corresponding main girder of cable anchor point change is more obvious. with the increase of cable damage degree, the deflection change is more obvious.Train load has little effect on the damage of cable tension, but will lead deflection changes of cable girder anchorage point to increase. So train load will amplify damage effect on the beam deflection.