| Because it has many advantages such as a simple structure, low cost and short duration, convenient erection and many other advantages, simply supported beams have been widely used in the transportation projects, especially the various small span bridges. Because of the apriority defects which are caused by their own design or construction problems, and the postnatal damage caused by overloading, accidents or natural corrosion, many bridges gradually appear steel bar corrosion, concrete cross-section defect, cracks and many other damages with the increase of service time. It affects the normal application of the bridge. Bridges collapse and many serious project accidents have been caused. So the study on the degree of typical damage harm and correlation has an important application value for the accurate evaluation and the conservation.In this paper, it was studied that the typical damage affects on the deformation and strength of reinforced concrete T beam and prestressed concrete box girder. Three parts have been included in the full text:There are four the typical damages of steel bar corrosion, concrete strength degradation, concrete cross-section defect and vertical cracks, and that these damages affect on deflection of beams has been discussed by using ABAQUS. Moreover the major damages combine two by two were calculated to study their correlation. The results show that the effect of vertical cracks and steel bar corrosion are more significant, secondly for concrete strength degradation. While concrete cross-section defect has a little effect on the deflection, it could be ignored.By theoretical analysis, it was discussed that damages affect on the flexural capacity and the shear capacity of two beams. The results show that the flexural capacity and the shear capacity of the beams have been largely impacted by steel bar corrosion and the shear capacity of the prestressed concrete box beam has been greatly affected by concrete strength degradation.Based on the results, two evaluation methods have been constructed. Their advantages and disadvantages have been studied and application conditions have been put forward. |
