LABORATORY STUDY ON DYNAMIC SOIL PILE STIFFNESS AND SOIL MODULUS

Abstract

The damages to engineering structures on piles in the past earthquakes have clearly demonstrated that for safe as well as economical earthquake resistant designs, understanding of the behaviour of the soil pile foundation system is very necessary and should be given primary impOrtance, As the development expands and oil industries extend their off-shore activities more structures such as feDd6*rs, dril1ing platforms, etc are built supported on piles. Damping and stiffness provided by the pile are the most important factors on which the response of structures to dynamic loads depend. These characteristics of the pile are a product of the interaction between the soil and the pi1e. For design of the pile foundation under dynamics lc)ads, the dynamic soil pile stiffness and soil mc}dulus. are used These parameters for the pile foundation are determined through experiments on prototype proposed pi_ie foundation installed in field for the purpose. A method was proposed by V. Ch@ndras**karan (1974) to find out these material constants i.e. soil pile stiffness and soil modulus. This method is standardised in IS code (IS:9716- 1981) and is in current practice" But no further work had been carried out in this direction to confirm if this is satisfactory. The present investigation is planned in laboratory iii ` if the proposed method gives unique results.