BULLETIN OF EARTHQUAKE SCIENCE AND ENGINEERING
Year:2015 | Volume:2 | Issue:3 |Papers Count:7

During an earthquake, the dynamic response of a structure located on a soil deposit could be very complex compared with the analysis of the same structure on bedrock due to the interactions between the soil and the structure. This phenomenon is technically termed as Soil-Structure Interaction (SSI) effects in literature. Most of what is currently known about soil-structure interaction (SSI) is based on theoretical and mathematical models. Therefore, it is necessary to investigate the structure treatments when they response to the ground strong motions transferred by SSI...

In the current study, a series of 1 g shaking table tests was performed to study the Tehran subway tunnel effect on the ground surface acceleration response. Two reduced-scale 1 g shaking table models, designated as FF and SF, were constructed in 1.32 scale. The FF was constructed to study the seismic response of the soil layer in free field condition, while the SF model includes a subway tunnel to study its effect on the acceleration response of nearby ground. In prototype scale, the subway tunnel with 8 m diameter and 0.35 m thickness was embedded in a soil layer with 32 m thickness...

Introduction Experimental and theoretical investigations indicate that the seismic bearing capacity of foundations is affected by earthquake excitation. In the present study, an analytical procedure is presented to obtain the seismic bearing capacity factor of shallow strip footing NgE for a foundation under inclined load on cohesionless soils. The limit equilibrium method with numerical iteration technique is utilized to calculate the seismic bearing capacity factor NgE. In the proposed analysis the Kotter’s equation and a failure surface consisting log-spiral and planar surface are employed. The results indicate that the seismic bearing capacity is reduced due to an increase in horizontal coefficient of earthquake acceleration. Besides, the results are in good agreement with solutions available in the literature...

During earthquakes, piles undergo stresses due both motion of the superstructure (i.e. inertial interaction) and that of the surrounding soil (i.e. kinematic interaction). In practice, structural engineers commonly take into account stresses induced by the inertial interaction, which is responsible for pile head failure, but they neglect the effects of the kinematic interaction that is responsible for failures along pile’s length in the case of layered soils with highly contrasting mechanical characteristics even in the absence of the superstructure. Thus, the evaluation of kinematic forces developing in piles during earthquakes has been receiving increased interest from the researchers...

In this study, the role of input motion characteristics on the amount of residual settlement of shallow foundations relied on liquefiable soil is investigated. First, two-dimensional numerical model is created using finite difference software FLAC-2D, and the UBCSAND constitutive model. After verification of the numerical model with the results of a centrifuge test, behavior of foundation is investigated under different earthquake loadings. To evaluate the effect of the input motion characteristics on foundation settlement, three records from Irpinia 1980, Northridge 1994, and Landers 1992 earthquakes are used. The frequency contents of these records are considerably different. These records are scaled to five levels of PGA (including 0.05 g, 0.1g, 0.2g, 0.3 g, 0.45 g) to be used in the analyses...

Progressive collapse starts with local destruction of a few elements of structures, which extends into a significant part of the building. Regular buildings are designed for dead, live, wind, earthquake and other normal loads. Nevertheless, there are other possible risks and loads, including firing, vehicle collision, gas explosion, design or construction error, bomb blast, etc. These risks occur very rarely, but they may cause a catastrophic collapse; therefore, for very important structures, they should be considered in the designing phase...

During the last 20 years, part of the research work has focused on the seismic analysis of Liquefied Natural Gas (LNG) tanks, due mainly to (1) the increasing number of LNG tanks constructed in seismically active regions, resulting from the adoption of LNG as an environmentally friendly fossil fuel, and (2) the catastrophic environmental impact, associated with a potential local or total failure of such tanks, caused by the earthquake motion...