Design And Research Of Hydraulic Pile Driver For Wheeled Highway Guardrail Pile

Wheel type highway guardrail pile hydraulic pile driver is a special construction machinery for highway guardrail pile installation and construction,the construction quality of guardrail pile is closely related to the performance of pile driver.At present,there are some deficiencies in the design of pile system and the research on energy saving of hydraulic system of pile driver.As a result,it is difficult for pile driver to identify pile position quickly under complex working conditions,and it is easy to produce large energy loss during pile driving.In this thesis,the key technologies of highway guardrail pile hydraulic pile driver are further studied,the overall structure and hydraulic system of the pile driver are designed,and the 3D model of the pile driver and the simulation model of the hydraulic system are established.The work efficiency,energy saving effect,movement characteristics and load bearing performance of pile system of the pile driver were studied by means of fluid dynamics simulation software,dynamics simulation software and finite element simulation software.Specific work contents are as follows:1.The overall design scheme of highway guardrail pile hydraulic pile driver structure is determined,and the 3D model of pile driver prototype is established by using Solid Works software.The structure composition and function of pile driver chassis system,power system,pile frame lifting structure,pile frame transverting mechanism,pile frame main mechanism and lifting guide rail mechanism are introduced respectively.The designed pile frame system has the function of finding pile position quickly and accurately.2.The design requirements of the hydraulic system are summarized.Based on the original quantitative hydraulic system of pile driver,the design scheme of the hydraulic system based on load sensitive control is determined.The energy loss in each working condition is analyzed and compared with the energy loss in the quantitative hydraulic system.It is concluded that the optimized hydraulic system has a higher energy utilization rate.The working principle of load-sensing variable pump and load-sensing proportional multiplex directional valve in hydraulic system is analyzed,and the law of energy loss in load-sensing hydraulic system is revealed.3.Based on AMESim,the optimized simulation models of the load-sensitive hydraulic system of the piling circuit and the original quantitative hydraulic system of the piling circuit are established respectively,and the model of the load-sensitive hydraulic system of the piling circuit is simulated and verified.The working characteristics of the two hydraulic systems are compared,and the influence law of the frequency of pile driving on the working parameters of the hydraulic hammer is revealed.The simulation results show that compared with the original quantitative hydraulic system of pile driving circuit,the load sensitive hydraulic system when the driving frequency is 40/3Hz,the impact energy is 148.46 J more,and the driving efficiency is increased by 18.49%;when the driving frequency is 20/3Hz,the impact energy is 228.38 J more,and the driving efficiency is increased by 9.44%.4.The kinematic simulation of the working device of highway guardrail pile hydraulic pile driver is carried out based on ADAMS,and the rationality of the movement is determined by analyzing its motion law.The dynamic simulation of the working device of the pile driver is carried out under the condition of pile bracket raising and pile driving,and the stress of the joint of each mechanism in the pile bracket system is obtained.5.Based on ANSYS,each component of the pile rack system was simulated under three working conditions: pile rack rising,pile driving and pile rack falling,and it was verified that the design of each structure met the static strength requirements.The modal analysis of pile driver is carried out and the conclusion that the pile driver will not resonate with the excitation source is obtained.There are 84 figures,11 tables and 90 references in this thesis.