Suspender Fatigue Study Of Half-through Arch Bridge

After the 19th century,half through bridge arch bridge by it's unique charm and structural characteristics of modelling in the rapid development of our country,has become one of the main bridge of our country. Suspenders is an important power transmission components,half through bridge arch bridge because of its small size,component part of many,It is more sensitive to fatigue corrosion factors,so the suspenders and its components operating condition is very complex. It is normal or not determines the safety of the bridge operation and longevity. But now has not kept pace with the development of the arch bridge,bridge design theory of suspenders design criterion,service life and damage of anticipation and so on all have no unified and scientific norms. Coupled with the bridge design personnel to attach importance to stress of the suspenders is insufficient,ignore the control of the suspenders fatigue and corrosion problem,the influential factors of the suspenders fatigue system comprehensive study have been carried out without,so suspenders damage phenomenon often occurred.Therefore, based on the reference,summarizes the existing research results, combined with the Shenyang existing bridge the existing bridge,suspenders,suspenders of the load behavior of the static and dynamic characteristics,influence factors of suspender is studied in-depth,comprehensive.This paper first Outlines the development present situation,characteristics and classify-cation of arch bridge, under the action of the suspenders in constant, the static and dynamic behavior are analyzed, and the fatigue problems in details of suspenders, illustrates the fatigue failure is a major cause of suspenders damage, the difference between the fatigue damage and static damage are introduced,summarizes the reason and mechanism of the suspenders damage,suspenders is given the current suspenders protection method,corrosion fatigue of fatigue cumulative damage theory and the suspenders has carried on the detailed introduction,fmally combining with Changqing bridge,using finite element analysis software to include within the span,the location of the suspenders and the suspenders wire material of three influencing factors of suspenders fatigue contrast calculation analysis,the following conclusions:(1) Reduce the suspenders appropriate spacing will not only reduce the stress of the suspenders and will be comprehensively improving the overall stress distribution of bridge. But the spacing is too small also adversely affect the fatigue of the hangers, sothe distance should be in the range of 4-10m;(2) Short suspenders is not only the reason of load fatigue damage problem, is by its own stiffness big,large deformation and structure and so on various aspects the result of the combination,the largest stress and stress amplitude fundamental appeared in the 1/4 span across and between position;(3) The rise to span ratio of Suspender Force influence is extremely small, determine the ratio of rise to span the main consideration of its iMPact on the overall stressof main beam and arch rib, at design time can ignore its impact on the fatigue of hangers.Suspenders fatigue problem more and more get the attention of the people,as time goes on, more and more Bridges using half through bridge arch bridge, the fatigue of the suspenders is also will be more and more diversified,in this study can be for the current and future reference and guidance for the bridge design work,has extensive application value and prospect.