Correlation Of Data Obtained By Shm System Of Urban Girder Bridge Under Operational Environment

The bridges under operational environment are often affected by the coupling of various environmental factors,how to use the correlation between the measured response of bridge structure under the operational environment to remove the influence of environmental factors on structural damage diagnosis effectively is a challenging problem.In order to solve this problem,this paper studies the relationship between Bridge structure response under environment,and proposes a method to construct the early warning threshold of bridge structure operation damage based on the response correlation relationship.This paper systematically sums up the research results and development trends of bridge structure response characteristics at home and abroad,and emphatically analyzes the key problems in the construction of response correlation relationship.Based on the massive measured data measured by the safety operation monitoring system of the bridge structure of the Yingxiong Mountain Road interchange,the change rule of modal parameters of the bridge is obtained by using the combination of environmental excitation technology and the implementation algorithm of feature system,and the finite element model of the bridge structure is established by the method of FEM model modification.The relationship between the measured response of bridge structure is studied emphatically.Based on the measured data of the environmental temperature and structure temperature,the spatial temperature field distribution of the bridge structure is obtained by statistical analysis,and the spatial correlation between the vibration displacement of the bridge structure is compared and analyzed based on the finite element model of the bridge structure and the measured data of the bridge's ambient temperature field.Based on the strain measured data of the key section of the superstructure,based on the finite element model analysis,the correlation model of the critical section strain response of the bridge girder is established,and the relationship between the frequency,the resistance damping,the vibration type and the ambient temperature is analyzed based on the mass measured data of the ambient temperature and structure modal parameters.On the basis of the above research,based on the 0-space theory,a structural damage diagnosis method is established,which is based on the displacement response correlation and the damage diagnosis early warning threshold value of the heroic Road interchange bridge;Based on probabilistic density estimation,a structural damage diagnosis method based on strain response correlation is establishedBased on the theory of principal component analysis and anomaly diagnosis algorithm,the damage diagnosis method of bridge structure is proposed to improve the principal component analysis,and the threshold value of damage diagnosis of bridge is established based on frequency correlation.Finally,the validity of the proposed algorithm is validated by using the measured response data of the bridge structure.