Finite Element Model Updating Of Arch Bridge Based On Static Test And It's Capacity Assessment

Now there are a number of arch bridges in our country, but the methods of bearing capacity assessment of arch bridge are relatively seldom. And it is necessary to study the bearing capacity of the evaluation methods of arch bridge.This paper is a part of the western traffic construction projects. And it focuses on using measured static displacement data to update finite element model. It sets up objective function on the basis of the deflection differences and assesses the bearing capacity of arch bridge.At first, this paper uses the plane beam element to establish the single arch model. And it uses the deflection difference of the measured value and calculated value. It updates the elastic modulus and moment of Inertia of the model by the optimization and gets the minimum of the objective function. In the end it shows that the method of the bearing capacity assessment on the basis of the optimization is right. And then the paper makes a method of the bearing capacity assessment of arch bridge. At first it sets up objective function on the basis of the deflection difference of the single working and updates the elastic modulus and geometric parameter of the model. And then it gives the medium loading working and unbalance loading working different factors and sets up the total objective function. It updates the model many times through adjusting the factors and gets the best solution. In the end, we use the updating model to get the ultimate bearing capacity.The method is applied to a reinforced concrete arch bridge. The result shows that the strains and deflections on the basis of the updating model are accurate and reliable. It tells us that the updating model can reflect the actual situation of the arch bridge. And the ultimate bearing capacity we get from the updating model is the actual bearing capacity of the arch bridge. This method only needs several workings deflections. And then we can assess the bearing capacity of arch bridge on the basis of the finite element program.