Mechanical Behavior of Kilometerlevel Cablestayed Bridge Under Static Loads

Abstract:

The paper presents a numerical analysis of the global mechanical behaviors of Sutong Bridge of China on the basis of the field static load tests.The results show that the bridge under the planned load test conditions is of good overall static properties and linear superposition characteristics, and incremental deflection is observed to be linearly proportional to incremental load. A good agreement is achieved between the experiential and analytical results such as displacements, stresses and cable forces. It is found that the measured maximum static deck deflections at the span centre is 1.388 m, maximum horizontal displacement of towers is 0.222 m, and maximum horizontal displacement of main girder is 0.107 m. Moreover, the stress level of the steel box girder under static loads is low, the longitudinal stress distributions of the slab and floor beam are nonuniform,the reasons for these phenomena include the shear lag effect and the influence of transversal slope of steel box girder as well as local stress effect of wheel load. And the Ushape ribs are of critical importance in fatigue damage assessment because of its alternating tensioncompression stresses.