Study On The Effect Law Of Bolted Joint On Dynamic Characteristic Of Plate-cylinder Structure And Research Of Experiment

Bolt joints are widely used in transportation,aviation,aerospace,energy,construction and all sorts of General Machinery Equipment by simple structure,convenient installation,flexible layout,etc.Research on dynamic characteristic of bolted joint structure has been one of difficulties in the field of dynamics because of many factors can influence it.For a specific bolted joint structure,materials,processing methods,processing quality and medium condition of bolted joint interface is determined.Now bolt pre-tightening force,bolt number and bolt distribution are the main factor influencing structure's natural frequency.Therefore study on the effect law of bolt pre-tightening force,bolt number and bolt distribution on dynamic characteristic of bolted joint structure is very important.Firstly bolted joint interface equivalent analysis model is established.The Hertz elastic contact theory and the normal contact stiffness fractal model is introduced.The mechanism of bolt pre-tightening force and bolt number influencing dynamic characteristic of structure are explained.Then modal analysis with bolt pre-tightening force is carried out in plate-cylinder structure by using finite element method.Based on the results,the effect law of the bolt pre-tightening force,bolt number and bolt distribution on the dynamic characteristic of plate-cylinder structure are studied.And the effect law is also studied when plate and cylinder's material is changing.Finally experimental modal analysis has been carried out,natural frequency of structure are tested in different condition.It is concluded that the effect law of bolted joint on dynamic characteristic of plate-cylinder structure by fixing the simulation results with the experimental results.