نوع مقاله : مقاله کامل پژوهشی
نویسندگان
گروه مهندسی عمران، دانشکده مهندسی عمران، دانشگاه ارومیه، ارومیه، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Seismic analysis of foundations is one of the key problems in geotechnical earthquake engineering. For this purpose, two general methods are proposed. In the direct method, the entire structure, foundations and subgrade are modeled in one step. But, in substructure method, the contribution of stiffness and mass of foundations in the analysis are considered separately. In this paper, the seismic response of strip surface footings under volumetric oblique incident waves SV, P and SH is investigated using boundary element method. For this purpose, at first, the impedance functions of the strip footing located on the semi-infinite soil mass are calculated using boundary element method with three-node quadratic elements. The calculated impedance functions depend on the frequency, the width of the strip footing, the shear wave velocity and the Poisson’s ratio of the soil mass. The input motion of strip footing which is subjected to volumetric inclined SV, P and SH waves are then obtained by using free field motion and the boundary element method. It can be seen that the displacement response of the foundation at the dimensionless frequency of 3, compared to the horizontal component of the free field motion of SH and SV waves as well as vertical component of P wave at angle of θ=30° are reduced 41%, 38% and %, respectively. By the way, as an example in time domain, the response of surface strip footing due to inclined SV wave with Ricker waveform is analyzed utilizing FFT algorithm.
کلیدواژهها [English]
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