Linear and non-linear analysis of soil column types proposed by the algerian earthquake resistant regulations (RPA 1999)

摘要

Seismic damage is strongly influenced by the dynamic response of soil deposits. The non-linear behavior and strength characteristics of soils govern their dynamic response during earthquakes. The measurement of dynamic soil properties is an important aspect of geotechnical earthquake engineering. Soils exhibit non-linear, inelastic, stress-strain behavior under cyclic loading conditions. At low strain levels, the stiffness of a soil is larger and the damping is smaller. At high strain levels, the effects of non-linearity and inelasticity increase, producing lower stiffness and greater damping. One-dimensional ground response analyses are based on the assumption that the ground surface and all material boundaries below the ground surface are horizontal and extend infinitely in all lateral directions. Although these assumptions are rarely satisfied in the field, they are used for engineering purposes at many sites. The equivalent linear approach provides the transfer functions to relate parameters of interest such as ground surface acceleration or velocity, to know parameters such as bedrock acceleration. The transfer function is influenced by the thickness, stiffness, damping characteristics of each soil layer and the bedrock properties. In this study, linear and non-linear analyses are carried out in order to analyze the non-linearity effects in time and frequency ranges of the responses of the soil types proposed by the RPA 99, and perform a comparative study between linear and non-linear analysis results. The soil profiles are subjected to two types of ground motions: near-field and far-field earthquake motions.