PTMD Vibration Control Method And Experimental Study Of Jack-up Platform

Tuned mass damper(TMD)is a common passive control device.Pounding tuned mass damper(PTMD)is a viscoelastic collision device based on TMD.It absorbs the kinetic energy and potential energy of the main structure to reduce structural vibration.In this paper,the vibration reduction effects of jack-up platform,PTMD and TMD are studied.The main work accomplished is as follows:(1)The research situation and basic theory of PTMD and TMD at domestic and foreign were introduced.Several common collision force models were analyzed.The basic characteristics of the collision force model were summarized.All the above have established the theoretical foundation for the further study of PTMD.(2)The ANSYS finite element analysis model was established according to the laboratory scale model.The natural frequency,mode shape,modal stiffness and modal quality of the model were extracted by modal analysis.According to the extracted model parameters,PTMD structure design was carried out,and the natural frequency range of PTMD was tested by hammering test to verify the effectiveness of PTMD structure.(3)The motion equation of platform-PTMD system was established.The influence of different parameters on the vibration control performance of offshore platform was analyzed by MATLAB-Simulink,included mass parameters,clearance ratio,impact stiffness and damping ratio.The robust characteristics of PTMD and TMD under harmonic excitation,free vibration and non-harmonic excitation were studied.(4)A test system for vibration control of jack-up platform was built.The effects of PTMD and TMD on vibration control of jack-up platform were studied.The natural frequencies of jack-up platform were obtained by exciting hammer test and the validity of PTMD was verified.The robust characteristics of PTMD and TMD under different tuning frequency ratios,excitation frequency ratios and random loads were studied and compared with numerical simulation to verify the correctness of numerical simulation.In this paper,the vibration control method for offshore platform is studied and designed,and the correctness of PTMD simulation results is verified by laboratory tests.The improved PTMD structure can resist the pre-denaturation of PTMD due to its own weight,and is more suitable for vibration control of offshore platforms.It has more practical guiding significance for solving engineering problems.