| With the improvement of the world’s ability to exploit marine resources,the pile of large diameter and super-long applies to bridges,ports,offshore wind turbines,especially offshore jacket platforms.Because of the heavy weight of piles and hammers,pile running always occurs when pile foundation is driven into some weak strata,which affects the construction safety and the progress of the project.For the phenomenon of pile running,there are most of the theoretical research at home and abroad,which are lack of the design research of device to prevent pile running,therefore,the design of anti-pile running device is necessary.Firstly,this paper combines the research status of pile running at home and abroad,and summarizes the phenomenological and theoretical analysis of pile running.According to the difference between clay soil and sandy soil,the calculation method of pile resistance is optimized by project examples,and the calculation method and steps of judging the pile running are summarized.Secondly,according to the project requirements,the overall structure of anti-pile running device and the detailed structure of key components are designed,and the hydraulic circuit is designed according to the working conditions and working principle of device.The three-dimensional solid model of the device and the steel pile are established by using Solid Works.Through mechanical analysis of the device,the relationship between the hydraulic cylinder thrust,the number of hydraulic cylinders,the wedge angle of friction block and the hydraulic thrust angle is obtained.On the premise of ensuring the safety and reliability of the device,ANSYS Workbench is used to analyze the stress and deformation of pile sleeve and to optimize the number of hydraulic cylinders.Then the model is imported to ANSYS Workbench for the finite element contact analysis,the wedge angle of friction block and hydraulic thrust angle are optimized.At the same time,based on the instability condition of steel piles,the strength of the friction teeth on the friction block and the stability and strength of the steel pile are analyzed to verify the rationality of the device and to ensure that anti-pile running device can play a role without destroying the steel piles.Finally,the preliminary design of anti-running pile device control is carried out.A software of the pile running section judgment which is developed by using MATLAB GUI,the early warning of the running pile is carried out according to the change of the penetration depth of the pile foundation in piling.The hydraulic system controlled by Siemens PLC is used to install anti-running pile device to ensure the normal installation and disassembly of anti-running pile device. |
