Study on longitudinal vibration of a viscoelastic pile by integral transformation and its application
WU Juntao1，2，WANG Kuihua1，2，GAO Liu 1，2，XIAO Si1，2，LI Zhenya1，2
(1. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China；2. Research Center of Coastal Urban Geotechnical Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China)
Abstract：The longitudinal vibration of a viscoelastic pile was derived by integral transformation method in this paper and the transfer and impulse response functions of pile-soil system were obtained as well. The analytical solution of displacement(velocity) at the pile top subjected to any form of excitation was derived by the convolution of impulse response function and excitation function. This method overcomes the limit of the method of separation of variables considering only the steady-sine excitation and extends the adaptability of the solution. Furthermore，a case study of low-strain integrity testing considering high-frequency disturbing signal was presented. Because of the existence of pile damping，the response to the high-frequency component of testing signal is filtered automatically，and the waveform of subsequently reflection corresponding to the low-frequency component is wide and flat at the same time. When the pile damping is very large，the location of the take-off point of reflection is shifted，and cannot be the basis for the test of one dimensional elastic wave velocity.
吴君涛1，2，王奎华1，2，高 柳1，2，肖 偲1，2，李振亚1，2. 考虑桩身材料阻尼的桩基纵向振动积分变换解及其应用[J]. 岩石力学与工程学报, 2017, 36(9): 2305-2312.
WU Juntao1，2，WANG Kuihua1，2，GAO Liu 1，2，XIAO Si1，2，LI Zhenya1，2. Study on longitudinal vibration of a viscoelastic pile by integral transformation and its application. , 2017, 36(9): 2305-2312.
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2017, Vol. 36 
