A Multiple Transversa Impact Performance Comparative Test And Research On Stainless Steel Reinforced Concrete Piers

Due to the fact that stainless steel displays superiority in strength,ductility,corrosion resistance,and maintenance costs,its use in replacing ordinary stressed steel bars in reinforced concrete structures has become a developing trend.As the collision between ship and all kinds of Bridges,the impact resistance of stainless steel reinforced concrete columns still remains an open question.In this study,stainless steel bars with the same diameter were used to replace stressed steel bars in ordinary reinforced concrete bridge piers,to conduct experimental research,theoretical analysis,numerical simulation on the impact resistance of the stainless steel reinforced concrete bridge pier specimen.The results of this study could potentially provide valuable references for impact resistance designs,as well as the evaluations of stainless steel reinforced concrete bridge piers.The major achievements of this paper are as follows:1.The research progress on the reinforced concrete structures under impact loads were summarized,the research on the mechanical properties of stainless steel reinforced concrete structures were outlined,and put forward the study on the stainless steel reinforced concrete structures under impact loads which need further study.2.Transverse impact performance test using an ultra-high drop hammer impact test system were performed on the two group of specimens which before and after the replacement of the same diameter under different impact energies.The test was carried to measure the impact,displacement,and strain time history curve of the specimen,as well as the derivation and development of the specimen's fractures during the impact process.Compared the differences on the impact,displacement,and strain between the specimens which before and after the replacement of the same diameter under different impact energies.The test results showed that,the maximum impact force,the maximum displacement at the specimen's top,and the maximum strain of the stainless steel reinforced concrete specimen was found to be lower than before the same diameter replacement under the same impact energy.3.A ZBL-U520 nonmetal ultrasonic detector was used to test the specimens,by analyzing the acoustic parameter changes after concrete damage,obtained the damage ofthe specimens which before and after the replacement of the same diameter under impact loads.The test results showed that,under the same impact energy,the damage of the stainless steel reinforced concrete specimen was less than the ordinary reinforced concrete specimen with the same longitudinal reinforcement diameter.4.For the specimens which before and after the replacement of the same diameter under impact loads,the initial impact velocity and maximum impact force could be viewed as a linear relationship.5.LS-DYNA was used to establish the finite element model of the specimen before and after the replacement of the same diameter.By analyzing the variation of the stress nephogram,obtained the main concentration of stress areas on the specimens which before and after the replacement of the same diameter are at the bottom of the impact back and near impact point.And compared the results of the experiment and finite element model of the impact,displacement,and strain time history curve of the specimen,the results were very well.