Study On BFRP Reinforced Corrosive Damaged Steel Tube Under Transverse Impact

As a common structural form,steel structures have been used extensively in industrial and civil buildings,bridges,energy mining and transportation.However,the steel structure will be affected by environmental factors such as atmospheric corrosion,seawater corrosion,wind vibration fatigue and so on for a long time in the course of service,which will cause various damage accumulation and defects in the steel structure,which will lead to the degradation of the bearing capacity of the steel structure members with the increase of time.Although the corrosion will not cause the steel structure to collapse directly during the service period,it will inevitably cause the structure to reduce ability to resist the impact load,which will lead to local failure and even the whole collapse,and then cause a major safety accident.FRP reinforcement technology is an effective method to improve structural performance,which has been highly valued in recent years in steel structure reinforcement.Nowadays,researchers have been concerned about the enhancement effect of FRP on the performance of steel structure,but less research on the performance of FRP reinforced damaged steel structure under dynamic load.This paper mainly studies the impact resistance after BFRP repair and reinforcement of corroded steel pipe,and analyzes the effect of BFRP on the performance of corroded pipe.Details of the study are summarized below:(1)A lateral drop hammer impact test was carried out for corrosion steel pipe and BFRP reinforced steel pipe.The effects of corrosion on the impact resistance of steel pipe and BFRP on corrosion steel pipe were compared and analyzed.According to the results,the impact force of steel pipe is reduced by corrosion,the deformation of steel pipe increases sharply,and the failure deformation mode of steel pipe is changed.By using BFRP to repair and reinforce,the impact force and the ability to resist the impact deformation can be obviously improved,the plastic deformation ability of the circular steel pipe can be reduced,and the overall stiffness of the specimen can be improved.(2)A numerical model BFRP reinforced corrosion steel pipe was established by using finite element software.Finite element analysis was carried out on the basis of the numerical model.By analyzing the parameters such as plastic deformation ability,impact bearing capacity and energy dissipation of the specimen,the working mechanism and properties of the BFRP reinforced steel pipe under impact load were studied and understand the effect of BFRP on the performance of corrosion steel tubes.(3)The reinforcement method of BFRP reinforced corroded steel pipe is designed to study the influence of different reinforcement methods on the performance of the specimen,including:BFRP paste method,BFRP paste length and BFRP paste layer number.By analyzing the performance of steel pipe under different reinforcement methods,the optimal scheme of BFRP repair and reinforcement is obtained.The results show that the comprehensive performance of the paste BFRP is the best in the way of[0~0/90~0],and the optimal repair and reinforcement effect can be achieved BFRP the L/2 is pasted along the length of the circular steel pipe.