【摘要】 针对成层地基中楔形桩的纵向振动问题,采用平面应变模型模拟桩侧土,并根据桩侧土的成层性及考虑楔形桩的变截面特性,将桩土系统划分为有限个微元段,运用Laplace变换技术和阻抗函数递推方法,求得了楔形桩纵向振动情况下桩顶复阻抗的解析解,并讨论了楔角对楔形桩桩顶复阻抗的影响。结果表明,动刚度曲线和动阻尼曲线的共振峰幅值均随楔角的增大而变大;当其他参数不变仅桩长变化时,动刚度曲线的共振峰幅值随桩长增大而变小,动阻尼曲线的共振峰幅值随桩长增大而变大;当其他参数不变仅桩端截面半径变化时,动刚度曲线和动阻尼曲线的共振峰幅值随桩端截面半径增大而变大。更多还原

【Abstract】 The longitudinal dynamic complex impedance of tapered piles in layered ground is investigated.Assuming the surrounding soil to be plane strain model and considering variable cross-section of the tapered piles and stratification of the surrounding soil,the pile-soil system is discretized into finite segments.Then,by means of the Laplace technique and the impedance function transfer method,the analytical solution of complex stiffness of the tapered piles under vertical exciting force is derived.Additionally,by means of parametric study method,the influence of the cone angle on the complex stiffness at the pile top is investigated.It is shown that the amplitudes of resonance peak of dynamic stiffness curve and dynamic damping curve increase as the cone angle increases.When the length of tapered piles is variable and other parameters are unaltered,the amplitude of resonance peak of dynamic stiffness curve decreases as the cone angel increases and the amplitude of resonance peak of dynamic curve increases as the cone angel increases.When the radius of tapered pile tip is variable and other parameters are unaltered,the amplitudes of resonance peak of dynamic stiffness curve and dynamic damping curve increase as the radius of tapered pile tip increases.更多还原