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Abstract Several earthquakes over the past two decades have demonstrated that bridges crossing fault rupture zones may suffer significant damage due to the combined effects of ground shaking and surface rupture. Although it is widely recommended to avoid building a bridge across a fault, it is not always possible to achieve this objective, especially in regions with a dense network of active faults. This review begins by compiling two databases: one of fault-crossing bridges damaged in past earthquakes and another of bridges crossing potentially active fault rupture zones. The article then continues to review findings of experimental, analytical and numerical studies, and to summarize seismic design provisions and recommendations related to fault-crossing bridges. The review ends with suggestions for future research directions in this area. Highlights • Information about fault-crossing bridges damaged in past earthquakes is collected. • A database of well-documented cases of bridges crossing potentially active faults is compiled. • Small- and large-scale experimental studies of fault-crossing bridges are reviewed. • Analytical and numerical studies of bridges crossing fault rupture zones are summarized. • Seismic design provisions and recommendations for fault-crossing bridges are discussed. [ABSTRACT FROM AUTHOR]

Buried steel pipelines transport large amounts of fuel over long distances and inevitably cross active tectonic seismic faults when seismic areas are traversed. Eventual fault activation leads to large imposed displacements on the pipeline, which may then fail due to local wall buckling or tensile weld fracture, having grave financial, social and environmental consequences. In this paper, flexible joints are evaluated as an innovative mitigating measure against the consequences of faulting on pipelines. Joints are introduced in the pipeline in the fault vicinity, aiming at absorbing the developing deformation through relative rotation between adjacent pipeline parts, which then remain relatively unstressed. The effectiveness of flexible joints is numerically evaluated through advanced 3D nonlinear finite element modeling. Extensive parametric analysis is carried out to determine the effect of pipeline – fault crossing angle, fault offset magnitude, joint angular capacity, burial depth and diameter over thickness ratio on the joint efficiency. The uncertainty regarding the fault trace is also addressed. [ABSTRACT FROM AUTHOR]

Surface fault rupture has caused significant damage to structures in several earthquakes. The propagation of the bedrock fault rupture through the overlying soil deposit has been studied by several researchers; however, the effects of fault rupture dynamics, as opposed to pseudostatic fault movement, have not yet been evaluated. There is the potential for dynamic effects to influence significantly structural damage due to the rapid rate of deformation imposed by surface fault rupture. Numerical simulations are performed to analyze the effects of the rate of fault rupture on dip-slip surface fault rupture for free-field and soil-structure interaction conditions. The numerical results indicate that in some limited scenarios, fault rupture dynamics can influence the amount of structural damage expected for a structure located near a fault. However, in most scenarios, fault rupture dynamics is expected to play a secondary role compared to fault, soil, and structural characteristics in evaluating building performance. [ABSTRACT FROM AUTHOR]

Abstract: An extensive investigation has been made into the interaction between topographic amplification and soil layer amplification of seismic ground motion. This interaction is suggested in the literature as a possible cause for the differences between topographic amplification magnitudes observed in field studies and those obtained from numerical analysis. To investigate this issue a numerical finite element (FE) parametric study was performed for a slope in a homogeneous linear elastic soil layer over rigid bedrock subjected to vertically propagating in-plane shear waves (Sv waves). Analyses were carried out using two types of artificial time history as input excitation, one mimicking the build-up and decay of shaking in the time histories of real earthquake events, and the other to investigate the steady-state response. The study identified topographic effects as seen in previous numerical studies such as modification of the free-field horizontal motion, generation of parasitic vertical motion, zones of alternating amplification and de-amplification on the ground surface, and dependence of topographic amplification on the frequency of the input motion. For the considered cases, topographic amplification and soil layer amplification effects were found to interact, suggesting that in order to accurately predict topographic effects, the two effects should not be always handled separately. [Copyright &y& Elsevier]

Abstract: Presented in this paper is numerical methodology to model and simulate behavior of piles in liquefiable soils. Modeling relies on use of validated elasto-plastic material model for soil skeleton, verified fully coupled porous media (soil skeleton) – pore fluid (water) dynamic finite element formulation, and detailed load staging of FEM models. A bounding surface elastic–plastic sand model that accounts for fabric change is used to model soil skeleton, while a fully coupled, dynamic, inelastic formulation () is used to model soil and water displacement and pore water pressures. Much attention is paid to accurate staged loading of the models, which start from a zero state of stress and strain for a soil without a pile, followed by application of self-weight, then by excavation and pile installation with application of pile self-weighting. Finally, seismic loading is applied followed by time to dissipate excess pore pressures that have developed. A total of six cases were modeled and simulated varying slope inclination, presence of pile–column and boundary condition for pile–column system. Presented are interesting and useful results that are used to deepen our understanding of behavior of soil–pile–column systems during liquefaction (lateral deformations, pile pinning effect, ground settlement). Moreover, detailed description of modeling is used to emphasize the availability and use of high fidelity modeling tools for simulating effects of liquefied soil on soil–structure systems. [Copyright &y& Elsevier]

Abstract: This paper presents results from numerical simulations of the propagation of an active dip–slip fault rupture through a uniform soil layer covering the rigid bedrock. Following verification of the numerical methodology against field evidence, a parametric study is performed for loose and dense sand, for normally consolidated and overconsolidated clay, as well as for different fault dip angles (normal and reverse faults) and for different thicknesses of the soil cover. The soil is modeled as an elasto-plastic, strain-softening material that obeys the Mohr–Coulomb failure criterion. The study aims at establishing criteria for the approximate depiction of the location and the width of the zone with significant ground surface distortion, where the differential ground displacements induced by the fault rupture may threaten the integrity of man-mad structures. [Copyright &y& Elsevier]