An efficient approach for assessing the seismic soil structure interaction effect for the asymmetrical pile group

All of the civil engineering structures involve some type of structural element which is in direct contact with soil. To estimate the accurate response of the superstructure it is necessary to consider the response of the soil supporting structure, and is well explained in the soil structure interaction analysis. Many attempts have been made to model the SSI problem numerically; however the soil nonlinearity, foundation interfaces and boundary conditions make the problem more complex and computationally costlier. To overcome this problem the attempt has been made to optimize the computational efficiency by applying the equivalent pier method for the deep foundation system. In this research paper the L-shape 11 storey building supported by a pile foundation with homogeneous local soil condition is analyzed for dynamic loading including the SSI effect. The significance of the SSI effect has been studied by comparing the responses of the system for fixed base and flexible base condition. A new approach has been proposed to provide simplicity in SSI modeling and reduce the computational cost (both memory and time wise). The approach includes the applicability of the equivalent pier method for the asymmetrical pile groups system, including SSI effect of the pile foundation system. The approach is validated for group effect and found that equivalent pile method can successfully be adopted and helps to reduce the computational cost of SSI problem. To understand the applicability of EPM approach, the parametric study has been carried out for different input of earthquakes and soil types. In accordance with this the three distinct earthquakes, including 1995 Chamba (M = 4.9), 1999 Uttarkashi (M = 6.9) and 2001 Bhuj (M = 7.7) and soil types including cohesive, cohesionless and C-Phi soils have been considered for SSI analysis. The study observed that, earthquake magnitude and soil type shows the major impact on the response of the SSI system.

[1]  M. Randolph.  Design methods for pile groups and piled rafts , 1994 .

[2]  Chandra S. Desai,et al.  Mixed finite element procedure for soil-structure interaction and construction sequences , 1985 .

[3]  Mihaela Movilă,et al.  Spectral Analysis for an Asymmetrical Structure Considering Soil Structure Interaction , 2014 .

[4]  J. L. Wegner,et al.  Dynamic wave soil structure interaction analysis of a two way asymmetric building system DSSIA-3D , 2009 .

[5]  L. John,et al.  Finite dynamic model for infinite media , 1969 .

[6]  E. G. Richard,et al.  A model for the mechanics of jointed rock , 1968 .

[7]  Young-Kyo Seo,et al.  Numerical Analysis of Piled-Raft Foundations Considering the Effects of Sand Cushion , 2007 .

[8]  Mehmet E. Uz,et al.  Seismic history analysis of asymmetrical adjacent buildings with soil-structure interaction consideration , 2011 .

[9]  Bijan Samali,et al.  Assessment of soil-pile-structure interaction influencing seismic response of mid-rise buildings sitting on floating pile foundations , 2014 .

[10]  Harry G. Poulos,et al.  Pile foundation analysis and design , 1980 .

[11]  Balakumar.  Experimental studies of model piled rafts on sand and field study of prototype behaviour , 2008 .

[12]  Jonathan D. Bray,et al.  Seismic soil–foundation–structure interaction observed in geotechnical centrifuge experiments , 2013 .

[13]  J. V. Perumpral,et al.  Mechanics of Three-Dimensional Soil-Structure Interaction , 1982 .

[14]  Kambala Siva Nagi Reddy..  Piles as settlement reducers in raft. , 2010 .

[15]  P. O. Van Impe,et al.  Deep Foundations on Bored and Auger Piles , 2009 .

[16]  Kazuo Konagai,et al.  Numerical analysis of nonlinear soil–pile group interaction under lateral loads , 2007 .

[17]  J. Wolf.  Dynamic soil-structure interaction , 1985 .

[18]  B. K. Maheshwari,et al.  Three-dimensional nonlinear analysis for seismic soil–pile-structure interaction , 2004 .

[19]  G. Russo,et al.  Numerical analysis of piled rafts , 1998 .

[20]  Jessica Daecher,et al.  Pile Foundation Analysis And Design , 2016 .

[21]  Faramarz Khoshnoudian,et al.  Extended consecutive modal pushover procedure for estimating seismic responses of one-way asymmetric plan tall buildings considering soil-structure interaction , 2014, Earthquake Engineering and Engineering Vibration.

[22]  Michael G. Katona,et al.  A simple contact–friction interface element with applications to buried culverts , 1983 .

[23]  Eduardo Alonso,et al.  Foundation analysis of an arch dam. Comparison of two modelling techniques: No tension and jointed rock material , 1985 .

[24]  Mark Randolph,et al.  Optimum design of piled raft foundations , 1997 .