Fatigue Safety Evaluation of Ezisting Reinforced Concrete Bridges
Generally,fatigue has not been considered as a key problem in the design of reinforced concrete bridges.Until the 1960s,reinforcement was mild steel and the stresses permitted in the steel bar and the concrete were such that fatigue and fracture failure was believed to be impossible.With the developments of reinforced concrete structures,higher working stresses were permitted and,in particular,high yield reinforcing bars were introduced.Design rules were issued to control cracking and to prohibit welding of reinforcement unless the risk of fatigue was negligible.In recent years,great deals of researches have been carried out,leading to a better understanding of the fatigue behaviors in concrete structures.Some studies showed that fatigue could occur in reinforced concrete structures in combination with other causes of deterioration.In the past eight years,considerable increases in traffic intensity and wheel loads have caused obviously fatigue damage in reinforced concrete structures in China.Some reinforced concrete bridges were damaged seriously,leading to the whole bridge collapse sometimes because of overloading and oversize trucks.So how to evaluate the fatigue safety of existing reinforced concrete bridges is an urgent problem in China.In the current paper,the assessment models of existing reinforced concrete bridges based on S-N curve and fracture mechanics approach were proposed considering the effect of overloading and oversize trucks.Finally the assessment method based on S-N curve and in-situ monitoring data was applied to a case study bridge.
ezisting reinforced concrete bridges fatigue damage assessment fracture mechanics
Chungsheng Wang Xiaohong Dong Wenhui Miao Gan Li
Department of Bridge Engineering,College of Highways,Changan University Middle Section of Nan Erhuan Road,Xian,Shaanxi Province,710064,P.R.China
国际会议
The 8th International Conference on Damage Assessment of Structures(DAMAS 2009)(第八届结构损伤评价国际学术会议)
北京
英文
749-756
2009-08-03（万方平台首次上网日期，不代表论文的发表时间）