The Sensitivity Analysis Of Girder Deflection To Stay Cable Damage Of Cable-Stayed Bridge

With the developing of the cabal-stayed bridge,more and more engineers started to approve it for its beauty and large span.The cable is one of cable-stayed bridge’s main bearing components,but it’s also damaged easily.With the service life growth, the cable’s damage is largely prominent,what’s more,a variety of external load.The serious damage of stay cables will lead to the bridge collapse.This thesis will choose the Han Wu cable-stayed bridge as the research object,which is two-span box girder. Analyze the change of the main beam’s deflection and the cable tensioncaused by the stay Cable damage.The main contents include the followings:(1)The three-dimensional finite element model is established according to Han Wu cable-stayed bridge’s actual size.Simulate a reliable calculation model after corrected the model,which refer to cable-stayed initial stress and the main beam’s Precamber given by design drawings.(2)In the case of cable lossless,the overall warming temperature loads are applied to the Han Wu cable-stayed bridge.The reference temperature is25℃.Analyze the changesof the cable’s tension and the main beam’s deflection caused by temperature load.(3)In the case of cable lossless, analyze the variation of cable’s tension and the main beam’s deflection caused by vehicle loads.(4)The cable’s damage is simulated through reducing cable’s modulus of elasticity.The damage is divided into three levels:10%,50%and100%.First,in case of the cable’s damage,analyze the variation of cable’s tension and the main beam’s deflection caused by gravity.Then,combine single cable’sdamage-50%with the temperature loads and vehicle loads respectively. What’s more,research the influence of cable’s damage on the main beam’s deflection and cable’stension.(5)Based on the analysis of massive calculation data and comparing reinforcement effect of each method,the great impaction of cable’s damage on the main beam’s deflection and cable’stensionis found.Under the temperature loads and gravity,the main beam’s deflection and cable’s tension vary significantly in the position of the damaged cable.Under the vehicle loads,cable’stension is influenced mainly by the vehicle loads,but the main beam’s deflection is influenced mainly by the cable’s damage.The vehicle loads could lead the deflectionchange greater.