【摘要】 饱和砂土在地震作用下会喷砂冒水,一些饱和土中打桩也会冒水,但目前都无法计算排水。根据Biot弹性两相饱和介质控制方程的固相与流相Green函数频域解析解,通过Sommerfeld积分,化为轴对称坐标下的形式,结合基桩的竖向振动方程与排水状态的Lamb积分公式,计算得到桩顶作用集中力时,符合Darcy定律的排水状态下饱和土中圆柱基桩的动刚度、饱和土孔压、排水量等重要参数,讨论了诸如桩径比等参数在排水状态下对桩的动力特性的影响。结论可供饱和土中桩基的动力响应与桩土相互作用的动力特性研究借鉴。更多还原

【Abstract】 Sand liquefaction and water drainage will occur at a saturated sandy soil site under earthquakes.Similar phenomena will also happen during pile driving.However,the drainage can not be calculated so far.Based on the solutions to the Green’s functions of the solid and fluid phases in frequency domain pertaining to the Biot’s governing differential equations of a two-phase saturated medium,the Sommerfeld’s integral and the transformation of axisymmetrical coordinate,dynamic equations and Lamb’s integral are combined to calculate the forces acting on a single pile driven under drainage.According to the Darcy’s law,the corresponding parameters such as dynamic stiffness of a cylinder pile,pore pressure and flux in the saturated soil are calculated when the pile top is subjected to concentrated forces.The effects of some parameters such as pile slenderness on the dynamic properties of piles are revealed.The results may benefit further researches on the dynamic response of piles in saturated soil and the dynamic properties of pile-soil interaction.更多还原