Dynamic Characteristics Research On Gear Transmission System Of Hydraulic Vibratory Pile Hammer Based On Piling Loads

With advantages of high capacity on pile driving and construction efficiency, wide range of working geology and little impact on the surrounding environment, hydraulic vibratory pile hammer is becoming a widely used environment-friendly pile driving machinery. For the gear system has to face complex factors such as soil mechanics, unique eccentric rotation load characteristics, various forms of internal and external incentives and lacking direct research, gear system of domestic pile hammer has problems such as high work noise, low reliability and short operational life during the vibration of pile driving process. In this paper, piling load analysis and dynamic characteristics of gear transmission system about hydraulic vibratory pile hammer is researched and the main contents shown as follows:1) Taking ZZY80hydraulic vibratory pile hammer as object, the inherent characteristics of gearbox rotor system of the vibratory pile hammer is researched by means of using finite element analysis tools. Research shows:resonant destruction of the system can be prevented by considering gear coupled modes which include single rotor dominant modal and new coupled modes generated by gear bending and torsion.2) On the basis of analysis and dynamics modeling about pile hammer system, the load characteristics of the pile hammer is simulated with soil dynamics and vibration theories. According to given geological conditions, load vibration resistance torque, pressure about hydraulic system, dynamic stiffness and damping about soil foundation, frequency characteristics near resonance is predicted.3) Taking double-shaft inertial vibration generator spur gear pair as research object, electro-hydraulic hybrid model about gear vibration system is constructed. Then, the impact caused by load vibration resistance, gear backlash, gear static transmission error and gear system damp on gear system dynamic characteristics is researched and simulated. What’s more, gear backlash which taken form ZZY80hydraulic vibratory pile hammer is optimized for reducing the gear dynamic load effectively, improving the dynamic performance and reliability of the transmission of vibratory pile hammer gears.4) The relationship about the hydraulic system pressure and pile depth under specific excitation frequency on construction location is researched by experiment, and the experiment can verify the correctness of loads theory and simulation analysis about gear system while piling.