Parameter Identification Of Bridge Structures Based On Data Under Static Load Test

Parameter identification algorithm of bridge structures based on measureddeflection under static load test is an effective method to determine the health of bridgestructures. In the past thirty years, scholars have done an extensive research on thefield of static parameter identification. However, there are some limitations whenexisting algorithms are applied to the bridge structures. Focusing on engineeringpracticality, the paper makes research as follows:(1)Bridge static load tests often use two-axis or three-axis loading vehicles.According to the characteristics of static load tests, the paper proposes a bridgestructure measured flexibility matrix method.(2)Parameter identification algorithm of bridge structures based on condensesensitivity of element node force is proposed in order to make full use of measureddeflection under static load test. And it discusses the physical meaning of the algorithm.It gives an practical engineering methods depending on physical meaning and ANSYS.(3)The paper complements the concepts of static parameter identificationalgorithm: it determins the procedure of parameter identification under the case ofowe-determined, relevant-determined, and over-determined, the principal ofidentifiability of structure parameters is given, it descripes the reason of sensitivitymatrix linear behavior-related and the criteria of judging the behavior of sensitivitymatrix, Monte Carlo analysis is used to deal with measurement error.(4)The similarities and differences of algorithm based on the error stiffnessvector, algorithm based on the error force vector, algorithm based on the errordisplacement vector, and the method of this paper through the accuracy, computationalefficiency, initial parameters, sensitivity matrix is proposed in order to fully understandthe static parameter identification algorithm.(5)The flexural rigidity of bridge structures is identified by using the measureddata of bridge structures of references and using the method of this paper. Thedeviation of the calculation of modified finite model and measured data is less than1%,which meets the engineering accuracy.(6)According to the test of a cantilever, It describes displacement measuringinstruments and data processing software. The flexural rigidity of the cantilever is identified by using the method of this paper. And modified model can effectivelypredict the response of the structure.