Finite Element Research And Its Optimization Of Cable Guardrail For Expressway

With the increasing requirement of automobile energy savings in our country,the automobile appearance is becoming more and more streamlined.As a new form of guardrail,cable guardrail is widely used in our country’s roads because of its superior toughness,strong collision absorption ability and reusability.Therefore,in today’s road traffic situation in China,it is of great practical significance to study the collision mechanism of streamlined automobile collision cable guardrail and optimize the barrier to improve the anti-collision performance of cable guardrail.Firstly,the traditional B-class cable fence and streamlined automobile model are established,and the collision parameters are set by LS-PrePost software.Secondly,LSDYNA software is used to simulate the collision of a vehicle with traditional cable guardrail.It is found that the conflict of a vehicle with cable guardrail occurs during the collision process.The result of collision analysis shows that the cable restraint decreases due to the premature failure of the hook,and the cable slips under the cover or body of the car,which eventually causes the front end of the car to drill out of the guardrail.When drilling and collision occurs,the maximum deformation of guardrail and acceleration of the vehicle mass center exceeds the limit of F83,which cannot guarantee the safety of passengers.Therefore,it is necessary in order to improve the guardrail to improve its safety performance.In order to solve the problem of automobile drilling into the cable guardrail,this paper presents an improved cable guardrail with vertical restraint device under the condition of the original cable arrangement,and simulates its collision with traditional cable guardrail under the same condition.It was noted that during the collision process,the car did not drill into the guardrail.Data of acceleration of vehicle mass center and maximum dynamic deformation of guardrail are all less than the limit value specified in the code F83,which proves the safety and reliability of the improved cable guardrail.Finally,the impact simulation of the improved cable guardrail and the traditional cable guardrail is compared and analyzed.It is noted that the obstruction effect of the improved cable guardrail and the ability to protect the car body and passengers have been improved to varying degrees.The influence of vertical restraint device on the simulation results of conflict is further discussed under different installation positions.To sum up,the safety performance of the improved cable guardrail has been optimized and can prevent streamlined vehicles from drilling into the guardrail.