Raft Foundation with SSI and without SSI Effects on Different Storey
Meghna Modi,  Noopur Shah
In practice, conventional method of analyzing the structure is by applying its base as FIXED/HINGED. In conventional structural design, SSI effects are not considered. In the present paper, an attempt has been made to carry out a parametric study for analysis of 3 bays x 3 bays space frames will be analyzed. The space frame is supported by raft foundation on Winkler’s spring bed. Winkler’s spring base is applied in STAAD.Pro by assigning nodal springs having value equal to soil stiffness at the base of discretized plate. The space frame is subjected to various combinations of gravity and earthquake loads. The space frame is analyzed keeping its base fixed and spring (soil) based on and plate mat based on the result of analysis, it is designed as per IS: 456 (2000) and IS: 1893 (2002). Based on Winkler’s hypothesis, the soil beneath the footing is modeled as bed of linear springs having stiffness equal to the modulus of subgrade reaction of the soil. The interactive analyses are carried out for 3 different values of modulus of subgrade reaction. A comparison of the maximum nodal displacements of the frame and the time period of the whole structure is done.
Keywords- Soil Structure Interaction (SSI), Winkler Hypothesis, STAAD.Pro
Cite this Article
Meghna Modi,  Noopur Shah,   "Raft Foundation with SSI and without SSI Effects on Different Storey"
, International Journal of Engineering Development and Research (IJEDR), ISSN:2321-9939, Volume.4, Issue 2, pp.764-766, May 2016, Available at :http://www.ijedr.org/papers/IJEDR1602135.pdf