Stress Impact Analysis Of The Round-ended Bridge Pier Anti-collision Box Made Of Sandwich Plate With Stiffening Ribs

With the progress of science and technology,development of new materials,and the emergence of a wide range of new materials,such as steel-polyurethane sandwich structure,comes into the engineer's field of vision.It is a composite structure formed by injecting polyurethane elastomer between two layers of steel to bond elastomer core material and steel plate surface strongly.This kind of sandwich plate structure has been developed and used abroad for more than ten years,for it has considerable stiffness,immense strength,and load bearing capacities.It is applied to ships,offshore oil platforms,bridges and other structures.Currently there are no appropriate specifications and instruction manual interiorly and the study is still in the early stage.In this context this paper is based on the Xiao Gang Bridge,which uses a finite element simulation method to build a steel-polyurethane sandwich plate box structure model,then analyzes the stiffening ribs effect on the anti-hit property of round-ended piers box sandwich plate structures and makes a sensitivity analysis toward the parameters involved.It provides a reference to domestic use of the new structure.First,this article lists the major bridge crash accident at home and abroad,and summarizes several anti-collision research methods of bridges and common anti-collision facilities.Chapter Two introduces the structural property advantage of steel-polyurethane sandwich plate as well as the classical theory on the structure of a composite sandwich plate,then emphatically introduces its application in practical projects.Chapter Three establishes the ANSYS finite element analysis model,which is based on actual engineering practice.Chapter Four first analyzes the box's mechanical performance under the condition of front collision,then it analyzes the change of mechanical performance of the sandwich plate anti-collision box after setting horizontal and vertical stiffening ribs in different numbers.The last chapter analyzes the effect when setting both horizontal and vertical stiffening ribs under a non-collision condition,while also analyzing sensitivity by changing different parameters,such as the impact angle and the number of stiffeners.In conclusion,the horizontal stiffening ribs in the sandwich panel can effectively reduce the vertical stress of the outer steel plate at the impact point of the sandwich panel and the transverse stress of the inner steel plate.However,when the number of horizontal ribs exceeds one it had little effects.It is necessary to set the vertical stiffening ribs to effectively reduce the stress of the outer steel plate at the impact point of the collision box and the vertical stress of the inner steel plate.In addition,under the non-collision condition,the peak of the stress at the impact point shows a decreasing trend with the increase of the impact angle.In the actual project,because the impact point is random,it should set a certain number of horizontal and vertical stiffeners,but should not be set too many,especially the number of horizontal stiffeners,otherwise it will cause labor waste,welding workload increases and structural weight increase and other unfavorable conditions,in the case of little change in stress is not conducive to box collision.