Piles-induced filtering effect on the Foundation Input Motion
Piles-induced filtering effect on the Foundation Input Motion
复制标题
桩引起的对基础输入运动的过滤效应
DOI：
10.1016/j.soildyn.2012.12.007
复制
发表时间：
2013
影响因子：
4
通讯作者：
L. Sanctis
中科院分区：
文献类型：
--
作者：
R. D. Laora;L. Sanctis
传统上，对桩基结构进行惯性相互作用分析时，假定基础输入运动仅为自由场运动，从而忽略了地震波通过时桩土之间的运动相互作用。这将导致设计中不必要的过度保守，因为有证据表明，自由场运动可能会被桩彻底过滤掉（通常会减少），特别是在软土的情况下，在这种情况下，桩经常需要承担上部结构传递的总荷载和/或减少基础沉降。分析和数值分析的结果阐明了控制过滤效应机理的关键因素。在对上部结构进行惯性相互作用分析时，还建议减少设计谱以考虑桩的有利影响。
The inertial interaction analysis of a structure founded on piles is conventionally performed by imposing that the Foundation Input Motion is merely that of the free field, thus neglecting the kinematic interaction between piles and soil generated by the passage of seismic waves. This would lead to unnecessary overconservatism in the design, as there is evidence that the free-field motion may be thoroughly filtered out by piles (generally reduced), especially in the case of soft soils, where piles are recurrently required to carry out the total load transmitted by the superstructure and/or to reduce foundation settlements. Results provided from analytical and numerical tools elucidate the crucial aspects controlling the mechanism of filtering effect. Reduced design spectra are also suggested to account for the beneficial effect coming from the piles when the inertial interaction analysis of the superstructure is being performed.