Research On The Structure Of Obstruction Block Of New Wave Beam Guardrail Based On Analysis Of Collision Process

The highway wave beam guardrail is the important traffic safety facility in China.It is composed of guardrail,the obstruction block and column.The obstruction block,as a connecting part between the guardrail and the column,the structural characteristics will affect the safety properties of the guardrail.A hexagonal obstruction block is set up between the guardrail and the column of the wave beam guardrail in China.However,this kind block structure is unable to prevent the vehicle from tripping,it will increase the severity of the accident when the vehicle is tripped.Therefore,it is necessary to study the structural characteristics of the block to improve the anti tripping characteristics of the block.The way to optimize the traditional hexagonal obstruction block is changing its shape and structure.The structure of obstruction block is optimized by computer simulation,the process of vehicle crash guardrail is simulated by Hyperworks and LS-DYNA software.Under the condition of equal mass,the structure of block is changed into rectangle structure and trapezium structure.According to the containment performance,the buffering performance and redirective performance in the Standard for Safety Performance Evaluation of Highway Barriers,the results of the test simulation and the safety evaluation of three kinds of obstruction blocks is carried out.It is concluded that obstruction block has the best anti tripping characteristics when the shape of obstruction block is trapezoid.In order to enhance the anti tripping characteristics of hexagonal obstruction block,steel plate is added to the hexagonal obstruction block to improve its non-deformability.However,according to the results of the test simulation,this obstruction block is not as good as the trapezoid obstruction block.In the study of the size parameters of the obstruction block,the trapezoid obstruction block is used as the research object.With the increase of obstruction block width,the greater the distance between the guardrail and the column,the better the barrier obstruction performance of the guardrail.But when the width is increased to a certain range,the anti tripping characteristics of the obstruction block have decreased,and the car body damage is becoming more and more serious.The height of the obstruction block does not improve the performance of the obstruction block.Therefore,the significance of optimizing the block is to prevent the contact area between the wheel and the column when a car collides with the guardrail,and increase the width of the block can effectively achieve this goal.It is proved by the actual vehicle collision test that the optimized block structure greatly reduces the probability of the trip resistance of the vehicle and reduces the severity of the accident.