复杂成层土中管桩振动特性分析

Analysis of Vibration Characteristics of Pipe Pile in Complicated Layered Soil

为了完善桩基检测理论及提高桩基检测质量,以地下水位面为界限,将管桩侧面土考虑为单相-饱和复杂成层土,进行了单相-饱和复杂成层土中管桩的纵向振动特性研究。首先根据地下水位面分界,分别建立了单相土层和饱和土层与管桩耦合振动的数学模型,然后进行了土体的动力方程求解得出管桩侧面土的剪切复刚度,根据阻抗传递性得到桩顶阻抗,进而得出速度导纳和速度时域的表达式,最后分析了地下水位面变化和地下水位面一定时桩土参数变化对桩顶动力响应的影响,并对比分析了相同参数下桩周土为成层单相土、单相-饱和复杂成层土、成层饱和土时桩顶动力响应的差别,得到了水位影响下复杂土中管桩耦合振动规律。

In order to improve the theory of pile detection and improve the quality of pile detection,the soil on the side of the pipe pile was considered as a single-phase-saturated complex layered soil with the groundwater level as the limit.The longitudinal vibration characteristics were researched.Firstly,according to the boundary of groundwater level,mathematical models of coupling vibration between single-phase soil layer and saturated soil layer and pipe pile were established respectively,and then the dynamic equation of the soil was solved to obtain the shear complex stiffness of the side soil of the pipe pile.The transmissibility pile top impedance was obtained according to the impedance transmission,and then the velocity admittance and velocity time domain expressions were obtained.Finally,the influence of the change of the groundwater level and the change of the groundwater level on the dynamic response of the pile top when the groundwater level changes were analyzed,and a comparative analysis was made.The difference in the vibration response of pile top when the soil around the pile was layered single-phase soil,single-phase-saturated complex layered soil,and layered saturated soil,the coupled vibration law of pipe-pile in complex soil under the influence of water level was obtained.