Impedances of soil layer with boundary zone

摘要: When calculating dynamic response of embedded foundations or piles, impedances (stiffness and damping) the adjacent soil are needed. To account approximately for nonlinearity under high strain, contact deficiencies disturbances caused by foundation installation, a cylindrical annulus softer around is used. The properties in this weakened boundary zone differ from those outer but both regions assumed to be homogeneous. mass can either neglected accounted for. If considered, seemingly more accurate approach, wave reflections interface between two media occur resulting marked undulations with regard frequency and, possibly, negative stiffness. It purpose paper show that such unrealistic featuring them less suitable practical application than obtained neglecting inner zone.