This paper presents a simple and stable procedure for the estimation of periods and dampings of piled shear buildings taking soil-structure interaction into account. A substructuring methodology that includes the three-dimensional character of the foundations is used. The structure is analyzed as founded on an elastic homogeneous half-space and excited by vertically-incident S waves. The strategies proposed in the literature to estimate the period and damping are revised, and a modified strategy is proposed including crossed impedances and all damping terms. Ready-to-use graphs are presented for the estimation of flexiblebase period and damping in terms of their fixed-base values and the system configuration. Maximum shear forces together with base displacement and rocking peak response are also provided. It is shown that cross-coupled impedances and kinematic interaction factors need to be taken into account to obtain accurate results for piled buildings.

The beneficial or detrimental role of battered piles on the dynamic response of piled foundations has not been yet fully elucidated. In order to shed more light on this aspect, kinematic interaction factors of deep foundations with inclined piles, are provided for single battered piles, as well as for 2 × 2 and 3 × 3 groups of piles subjected to vertically incident plane shear S waves. Piles are modelled as linear-elastic Bernoulli beams while soil is assumed to be a linear, isotropic, homogeneous viscoelastic half-space. Different pile group configurations, pile-soil stiffness ratios and rake angles are considered. The relevance and main trends observed in the influence of the rake angle on the kinematic interaction factors of the analysed foundations are inferred from the presented results. An important dependence of the kinematic interaction factors on the rake angle is observed together with the existence of an inclination angle at which cap rotation and excitation become out of phase in the low-to-mid frequency range. The existence of a small batter angle that provides minimum cap rotation is also shown.

This paper aims to contribute to clarify whether the use of battered piles has a positive or negative influence on the dynamic response of deep foundations and superstructures. For this purpose, the dynamic response of slender and non-slender structures supported on several configurations of 2 × 2 and 3 × 3 pile groups including battered elements is obtained through a procedure based on a substructuring model which takes soil-structure interaction into account. Results are expressed in terms of flexible-base period and maximum shear force at the base of the structure. Moreover, modified response spectra considering soil-structure interaction effects are provided for different rake angles. It is shown that an increment of the rake angle can result in beneficial or detrimental effects depending on the structural slenderness ratio.

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