分数导数黏弹性模型描述的土中单管桩的水平振动

将土体视为黏弹性介质,采用分数阶本构方程描述黏弹性土应力-应变关系,建立并求解了在轴对称坐标下单桩桩周-桩芯土水平振动控制方程,得到分数阶黏弹性土体单桩水平动力阻抗的解析解形式.通过数值算例分析了桩土常数和模型参数对单桩水平动力阻抗的影响.结果表明:桩周土的分数微分算子阶数对单桩水平动力阻抗影响较大;桩芯土和桩周土的本构模型常数会对水平动力阻抗刚度因子产生明显影响,而对阻抗因子的影响相对较小.

Studies on Horizontal Vibration of Single Pile in Fractional Derivative Viscoelastic Soil

The soil is seen as a viscoelastic medium. Fractional constitutive equations are used to describe the stress-strain relationship of viscoelastic soils. The horizontal vibrational equations of the soil-sill core soil around a single pile are established and solved under axisymmetric coordinates. The analytical solution of horizontal dynamic resistance of single pile in fractional viscoelastic soils is obtained. The numerical examples are used to analyze the effect of pile-soil constant and model parameters on the horizontal dynamic resistance of a single pile. The results show that the fractional differential operator order of the soil around the pile has a great effect on the horizontal dynamic resistance of the single pile; The constitutive model constants of the soil around the soil and the pile have a significant effect on the horizontal dynamic impedance stiffness factor,while the influence on the impedance factor is relatively small.