Soil structure interaction of multi storey buildings on raft foundation under dynamic loads using FEM GPR LSSVM and MPMR

Abstract

The rapid development of urban population and the pressure on limited available space newlinesignificantly influence the residential development of the cities in India and abroad. The high newlineprice of land, the desire to avoid uneven and uncontrolled development of urban area and the newlineneed of land for important agricultural production have all led to route the residential newlinebuildings upward. The local topographical restrictions in the urban area are only possible newlinesolutions for construction of multi-storey buildings to fulfill the residential needs and other newlinerequirements. newlineAn understanding of the interaction between a structure and its supporting ground is of great newlineimportance in the design of safer structures and foundations subjected to earthquake motions. newlineIn general practice, structures are analyzed considering the base of structure as fixed and newlineassuming the ground motion at the base of the structure same as the free-field motion. Freefield motion is defined as the ground motion that would occur at the level of the foundation if newlineno structure was present. However, foundation motions deviate from free-field motions as a newlineresult of the presence of stiff foundations, wave inclination or incoherence or foundation newlineembedment. Inertial forces developed in the structure by foundation motion during newlineearthquake will cause base shear and moment, which in turn will induce relative newlinefoundation/free-field motions due to the foundation compliance. These phenomena combined newlinetogether are commonly termed soil-structure interaction (SSI). newlineWhile analyzing a beam on an elastic foundation by the theory of subgrade reaction, it is newlinenoted that settlement (y) is dependent on the bearing pressure (p) also, as much as p is newlinedependent on y, or in other words, one cannot determine y independent of p. The effects are newlinethus found to be not independent but mutually dependent or inter-dependent and interactive. newlineHerein lies the concept of true interaction in the problem.