Study Of Fluid-solid Interaction Vibration Characteristics And Control Of Hydraulic Vibratory Hammer’s Main Pipeline

With advantages of high capacity on pile driving, low noise, small damage to pile, and also wide range of working geology, hydraulic vibration pile hammer is becoming a main pile foundation construction equipment of both domestic and overseas. However, due to the pump’s flow pulsation, particularly since the impact of drastic changes in the external environment such as strong vibration of vibratory hammer and load of foundation soil during pile driving, the pipeline system of hydraulic vibratory pile hammer has long been intense vibration and frequent damage. Taking ZZY160hydraulic vibration pile hammer as object in this paper, vibration characteristic of main pipeline of vibration hammer during pile driving and vibration control technology are studied, the main contents shown as follows:1. Using the analysis method for foundation soil load characteristic, in consideration of the influence of pipeline characteristics and the pump flow pulsation, this paper establishes the model of vibration pile hammer hydraulic system. This paper carries on numerical simulation of oil flow in the piping process by using AMESim, and it gets dynamic characteristics of the flow and pressure of oil during the entire construction process.2. Taking into account the oil’s compressible and viscous properties, the math model of interaction system of hydraulic pipe and compressible viscous oil is established in this paper, which applied to high speed, high pressure and high power of pile hammer hydraulic piping system.3. Considering the influence of vibration pile hammer’s local structure vibration, combined with dynamic load characteristic analysis method facing to ground soil, the vibration characteristics of hydraulic vibratory pile hammer pipeline during pile sinking process are studied by using ANSYS and CFX finite element simulation based on hydraulic pipe and compressible viscous oil interaction model. The generating mechanism of resonance on hydraulic pile hammer’s main pipeline is clarified. By adding clamps and accumulator, vibration control of the hydraulic main pipeline is investigated in the paper.4. The field vibration experiment on hydraulic vibratory pile hammer’s main pipeline is carried out, and the experiment verifies both the simulation analysis about vibratory pile hammer’s main pipeline and the set of resonance control program are correct.This research has theoretical and engineering practical value of predicting natural frequency and displacement response of hydraulic vibratory pile hammer’s pipeline under the piling condition and adding clamps in a reasonable position to avoid resonance. This paper can provides important reference foundation for installation and vibration control of complex pipeline.