| As for static or dynamic investigation, the results figured out based on interactive SPS are deviate from that based on fixed-base hypothesis structure and the loading and deforming features exhibited in interactive system under the condition of various soil-layer, soil properties and pile-groups properties etc are also discrepant, so the interactive design of whole foundation and superstructure parts are necessarily and primely emphasized by numerous researchers in engineering practice. Despite the different keystones which structural engineering and geotechnical engineering emphasize respectively in aseismatic interaction analysis of upper-lower parts under horizontal earthquake, that is inertial feedback interactions of the structure subsystem to the former or kinematic interactions of the pile-soil foundation subsystem to the latter, but the dual effects of soil fields mustn't be ignored. So the topic for farther discussion will be developed on the ground of soil-foundation-structure interactions, and emphasizes particularly on the investigation for dynamic effects on interaction of pile-supported structures subjected to lateral seismic load at layered-soil media. It will provide engineering application with practical and concise computational method, but also provides the aseismatic design for pile-supported structures with proper theory foundations and schemes to some extent on condition that definite codes are absent at present. The full article is divided into six chapters, as follows:1. With the summarization of lots of interrelated references, the studying actuality and developing level which about soil-structure interaction are presented. The limitations advantages and disadvantages existing in present researches are discussed too. Then the basic theory way and analyzing frame route related to upper-lower structural parts with pile-groups in this paper is introduced.2. The whole dynamic finite-element analysis simplified based on 2D plane is performed to adapt engineering requires. The effect of both kinematic interaction and inertial interaction on pile-soil-structure systems within layered soil field is relatively comprehensively investigated. At the same time, the boundary effect of model , the horizontal dynamic features of piles and the nonlinear characteristic of slide and contact on the interfaces of pile-soil are considered too on the ground of no-elementmeshing technique applied for dimensional effect of piles in stratum-soils.3. Following natural layered characteristic of soils, a simplified 3D nonlinear dynamic model of pile-supported superstructure system in time domain is presented. So the various time response histories of structures are realistically described and the seismic field-movements of the system are simulated under different working conditions such as various earthquake waves elasticity or elastoplasticity of soil and pile-soil contact etc. The linear or nonlinear characteristics of histories response of upper-lower structural parts under seismic are prominently re-shown by means of gradual meshing finite-elements for near-far fields with the 3D spring-dashpot boundary elements. Based on the above analysis, many designs and tests about interactive structures may be developed accurately.4. Instead of the applicability problem of some intricate numerical technique in dealing with large number piles and alterable type of pile-groups, based on the dynamic winkler-foundation beam model and Haskell-Thomson transfer matrix scheme, the explicit expressions indicating force-displacement relationship of pile are derived under simultaneous axial and lateral loads in layered-soil in order to obtain the displacements and internal forces of pile-foundation in frequency-domain. In terms of the Gazetas's three-step procedure for pile-soil-pile interaction in homogenous media a new method for calculating dynamic interaction factors of layered-soil considering the influence by axial load is suggested under harmonic exc...
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