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| ANALYSIS OF VERTICAL VIBRATIONS OF A RIGID FOUNDATION RESTING ON SATURATED POROELASTIC HALF-SPACE SUBJECTED TO INCIDENT PLANE WAVES |
| (1. Key Laboratory of Soft Soils and Geoenviromental Engineering of Ministry of Education，Zhejiang University，Hangzhou，Zhejiang 310058，China；2. College of Architecture and Civil Engineering，Wenzhou University，Wenzhou，Zhejiang 325035，China) |
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Abstract An investigation is put into the vertical dynamic responses of a rigid circular foundation on the poroelastic soil excited by incident fast P1 waves and SV waves. The radiation field and rigid-body scattering field are introduced in order to consider the dynamic interaction between the foundation and the underlying soil，as well as the scattering phenomena caused by the existence of the foundation. The motion of the soil is supposed to be governed by Biot¢s dynamic poroelastic theory，while the boundary conditions along the contact surface between the soil and the bottom of the foundation are assumed to be perfectly bonded for the skeleton and hydraulically drained for the fluid. Combining with the mixed boundary-value condition and the dynamic equilibrium equation of the foundation，the expression of the vertical dynamic amplitude of the foundation，subjected to the incident plane waves，is obtained by solving the control equations using Hankel integral transforms. The influences of incident angle，the mass of the foundation and the permeability of the soil on the vertical vibrations of the foundation are thus determined through numerical simulations. Significant differences are found between the responses of the foundation，which is excited by fast P1 waves and SV waves，respectively.
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Received: 25 January 2010
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2010, Vol. 29 
