Study On The Design And Simulation Of The New Type Hydraulic Impacting Piling Hammer System

This paper is combined with the scientific and technological development projects in Jilin Province, "the study of new hydraulic piling hammer development". Summing up the hydraulic piling hammer at home and abroad on the basis of research results, the author put forward a new type structure of hydraulic piling hammer to research the modeling and simulation technology of a new hydraulic piling hammer virtual prototype composed by the mechanical, hydraulic and control parts. On this basis, we manufactured the physical prototype of hydraulic piling hammer, test the performance of the new type of hydraulic piling hammer and verified the simulation results . This paper has a certain academic value for the study of multidisciplinary complex electromechanical product modeling and simulation technology, new hydraulic piling hammer is of great significance for improving the design and application of the modernization construction of China's technological level. The main research results are as follows:1. On the basis of reading a wide range of domestic and international literature, the author summed up the hydraulic piling hammer research and application status quo and the trend of hydraulic piling hammer development. Based on the virtual prototype that the multidisciplinary modeling and simulation technology is the necessary channel of the development of new highly efficient hydraulic piling hammer, through digital virtual prototype hydraulic piling hammer structural dynamics, kinematics, strength and performance of such areas can be created, assembly of simulation analysis in order to obtain the product of the performance prediction and analysis of the results. This paper introduced the virtual prototyping technology and development platform.2. On the basis of impact analysis of hydraulic piling hammer work the mechanism, to get the work smooth, efficient, and compact structure for the goal, carry through the conceptual design of a new type of hydraulic piling hammer impact , a new hydraulic piling hammer use nitrogen - Hydraulic cylinder storage to compact structure, interim tank for oil decreases resistance by filling a hollow dielectric hammerhead extended against time. Carry through the impact of the proposed new hydraulic piling hammer evaluation index system, which includes functional evaluation index, effectiveness evaluation indicators, stable evaluation of environmental indicators and indicators.3. This paper proposed the method and control system theory and system design of the new type of hydraulic system hydraulic piling hammer main parameters .The main control system of Hydraulic piling hammer is composed by systems management, movement controller, drive circuit and the implementing agencies, sensors and signal processing circuit constitute. Hydraulic piling hammer products to a large extent depend on the performance of the control system. Control system has the following features:①the hydraulic circuit for the process used the "first opened after the Commissioner of the" design criteria, in terms of hardware with two cartridge valve construct a two three slide-valve function, take the form of dual-channel control;②impact weight, the whereabouts of acceleration, impact and combating trip frequency can be adjusted for different conditions of the construction site of the fight against the achievement of the desired process.4. Multi-filed modeling method based on virtual prototyping software- ADAMS for new type of concept hydraulic pile hammer was put forward. Creation of model agencies, and the constraints imposed on the method of restraint, as well as redundant checks and modification method in ADAMS was introduced; hydraulic system model of hydraulic pile hammer was found using ADAMS/Hydraulics;the mechanical system was coupled with the hydraulic system in ADAMS and control system and other systems were related by the establishment of step function ,so the virtual prototyping of impact hydraulic pile hammer was finished. At the same time, by applying finite element method to the strength calculation of the hydraulic piling hammer and studying the system compose by hydraulic pile - pile– soil, local hammerhead finite element stress analysis of the dynamic model and the overall impact Analysis model were established. The interaction among pile hammer, hammer pads, caps and pile pad, and transfer mechanism in the process of hammering were simulate, by proposing the interaction between pile and soil as the boundary conditions, and overall assembly nonlinear dynamic Analysis model composed of hammer assembly, hammerhead assembly, Hammer covered assembly, fuel tank assembly, and Anvil caps assembly etc.5.Because of the process of hydraulic piling hammer impacting the caps was a nonlinear dynamic process which involving geometric nonlinear, material nonlinear and contact nonlinear ,confirmation of boundary conditions and Numerical algorithms for hydraulic pile hammer dynamics impacting process were discussed,and providing theoretical supports for hydraulic pile hammer nonlinear analysis. The simulation analysis of the new hydraulic piling hammer work performance was taking, using virtual prototype model. The interaction among pile hammer, hammer pads, caps and pile pad, and transfer mechanism in the process of hammering were simulate, based on overall assembly nonlinear dynamic Analysis model composed of hammer assembly, hammerhead assembly, Hammer covered assembly, fuel tank assembly, and Anvil caps assembly etc. The stress transformation of Hammer key point in the impacting was get, and effects of hammerhead key point dynamic stress caused by hammer pad stiffness,the pile pad rigidity,pile stiffness,soil type,Hammer quality,hammer early speed,the system damping and other key parameters were analyzed。The results show that: strength of the hammer shell was sufficient under transient load hit; hydraulic hammer pile overall bearing capacity was good; hammerhead stress was impact heavily by the hammer pad stiffness and pile pad stiffness , but the impact of cushion damping was little ;Effect on the hammerhead dynamic stress caused by Hammerhead early speed and quality was also very important. Influence on the hammer key points dynamic stress caused by various parts stiffness parameters, quality parameters and speed parameters, damping parameters were discussed ,and providing theoretical basis for the hammer dynamic structure design.6. Based on virtual prototype simulation , a new type of hydraulic piling hammer physical prototype was developed; the performance of hydraulic pile hammer was studied, hydraulic system parameters,vibration parameters of every point and simulation results in the process were compared; the virtual prototype simulation results were verified。Among the main points are summarized as follows innovation: (1) A new hydraulic impact hammer design with high transmission efficiency, stability of work and compact structure was put forward. The single nitrogen storage hydraulic cylinder was used in this hydraulic cylinder, while in work there was Only one cavity access to oil flow, hammer was droved by Cylinder,hammer piston rod also offered Pre-oriented and the structure was compact . Hammer shell also offering as transit tank, which not only reduces the fuel tanks for oil pressure, and also improved heat dissipation. In addition, the hydraulic cylinder used hollow-Hammer, filled in the internal, extended the time of pile penetration, and improved working stationary.(2) The author put forward the method of hydraulic pile driver virtual prototype modeling covering areas such as machinery, hydraulic and control, using virtual prototyping to simulate the operating performance of pile hammer, and the simulation results and experimental results agree well ,virtual prototype simulation provide means for the development of hydraulic piling hammer and parameter optimization.(3) Making the system of Hydraulic hammer-Pile-Soil a target, the author established a hydraulic pile hammer non-linear dynamic analysis model, and the model taking into account a hydraulic piling hammer in the process of the non-linear geometry, materials Nonlinear state and nonlinear. Using the interaction between the soil and pile as boundary conditions, a typical hydraulic piling hammer dynamic operating conditions of stress and deformation analysis had been done, we can obtain the key components of hydraulic piling hammer distribution of the dynamic stress and deformation law and the rigidity of the component parameters, quality parameters and speed parameters, damping parameters on the key points hammer the influence of dynamic stress, which provided a theoretical basis for the Hammerhead structure dynamic design.