The study presented in this paper focused on developing accurate computational finite element (FE) model of electrical substations ceramic (porcelain) post insulators. The objective is to investigate the structural behavior and seismic response of these critical equipment through detailed numerical simulations that can replace or minimize experimental qualification tests and optimize future design

A novel experimental/numerical hybrid methodology for the assessment of railway-induced ground-borne vibration in buildings based on experimental measurements in the soil surface is proposed in this paper. This methodology has been specifically designed for the prediction of railway-induced vibration in buildings to be constructed close to an operative railway infrastructure, although it can be applied

A modified simplified analysis method is proposed in this paper to evaluate seismic responses of subway stations in dense urban environments. Based on the dynamic analysis of the underground structure-soil-adjacent building interaction (SSSI) model, the seismic response of subway station was distinguished as the kinematic interaction (KI) effect (induced by the free-field movement) and the inertial

This study aimed to understand the optimal characteristics of friction dampers considering sway-rocking (SR) motion in vibration control structures during earthquakes. The nonlinear seismic response was numerically obtained using a six-story reinforced-concrete building model with a friction damper and SR springs and damping elements. The results indicate that the SR case shows a less sensitive response

Kinematic soil-structure interaction (SSI) effects cause foundation-level motions to deviate from free-field motions. Simplified procedures to account for kinematic SSI effects are available in design guidelines for regular buildings and have been calibrated for regular buildings with limited foundation size and depth of embedment. As a result, their application to structures with much larger foundation

Recent studies evidenced that non-structural damage in buildings caused by earthquakes leads to high economic losses and can represent a threat for life safety. Particularly, piping network damage has been widely documented in post-earthquake inspections. In this study, a cascade analysis is conducted to evaluate the seismic demand on two types of piping networks installed in a reinforced concrete

Microseismic (MS) source location is a core technology in MS monitoring that helps to infer the mechanical state of the rock mass and prevent dynamic disasters. However, when considering P-wave arrival time system errors (PATSEs), conventional location methods encounter the problem of high inversion dimensions and do not consider the influence of large P-wave arrival time errors. Therefore, we proposed

To investigate the source properties and focal mechanism of coal and sandstone specimen rupture under uniaxial loading, acoustic emission (AE) testing of sandstone and coal specimen rupture under uniaxial loading was conducted. The spatio-temporal evolution of AE parameters in the rupture process was determined through the AE testing of coal and sandstone specimen rupture under uniaxial loading. The

Practice-oriented finite element (FE) modelling strategies represent a fundamental tool for the seismic analysis and design of Cross Laminated Timber (CLT) structures. Although substantial research has been undertaken concerning the seismic behaviour of CLT buildings, practice-oriented FE modelling strategies are still at an early stage. This paper presents an upgrade of an existing practice-oriented

2-D resonances are known to occur in sedimentary basins, and it has been reported that the fundamental mode shapes appear to reflect the bedrock shape. This suggests that the bedrock shape of a valley can be estimated by evaluating the relationship between the mode shapes and the bedrock shape, and by identifying the resonance modes from the observation records of the ground motions. In the present

The effect of particle size distribution (PSD) of coral sands on the failure behavior of cemented coral sand specimens is investigated in this study. A series of static and impact loading tests on the specimens with various grain grading curves have been carried out. Test results show that the compression strength and impact resistance of the cemented coral sand specimen are increased with the increasing

Ground motions with strong pulse-like features are of special concern for structural engineers. Detection and characterization of the pulse-like features are fundamental in seismic hazard analysis, ground motion selection/simulation, and structural analysis. From the perspective of earthquake engineering, a pulse-like feature in a ground motion is of significance only if it dominates certain structural

This study proposes a novel air spring–friction pendulum system (FPS) three-dimensional isolation bearing composed of an FPS for horizontal isolation and an air spring for vertical isolation. The bearing has low vertical stiffness and a strong deformation capacity, which can effectively isolate long-period ground motions. A theoretical mechanical model of the three-dimensional isolation bearing is

A reliable prediction of the excess pore pressure build-up is essential in performing an effective site response analysis. In this study, centrifuge test measurements on mildly sloping ground subjected to ramped sinewaves are utilized to test the performances of three pore pressure models implemented in a one-dimensional (1D) site response analysis program conditioned on accumulated strain, energy

Recently, the application of deep hole presplit blasting (DHPB) in underground-engineering excavation has increased, but the research on deformation characteristics and failure mechanism of DHPB is relatively less, and lack of relevant numerical simulation verification. Owing to the above situation, the deformation characteristics and failure mechanism of DHPB are obtained through numerical simulation

Previous earthquakes have highlighted the seismic vulnerability of fault-crossing multi-span simply supported (FC-MSSS) bridges due to the large displacement of decks. Restraining devices, being of low cost and easy to install, can be a potential alternative to prevent the large displacement or falling of bridge spans for FC-MSSS bridges. However, the current restrainer design guidelines cannot provide

Resilience of bridges in seismic zones can be realised by taking the advantage of rocking isolation which aims at reducing the permanent drifts after a seismic event. The seismic forces at the base of the bridge can be reduced by allowing uplift in the foundation when subjected to ground shaking. Conventional monolithic connection of bridge pier to the foundation often leads to severe damages (or even

Bucket foundations have been increasingly used to support offshore wind turbines as alternatives to monopiles and can be classified into two types: monopod and tripod/jacket supported on multiple shallow foundations. Despite the recent research on the bearing capacity and stiffness of skirted foundations, knowledge regarding the monotonic and cyclic responses of multiple bucket foundation systems in

During the 2016–2017 Central Italy earthquake sequence, a series of moderate to large earthquakes M > 5 occurred near the Amatrice and Norcia towns. These events are recorded on a dense seismic network, providing relevant observational evidence of complex earthquakes in time and space. In this work, we used this substantial data set to study the ground-motion characteristics of the Norcia earthquake

Liquefaction is a phenomenon through which saturated sandy soil loses its shear strength and turns into a liquefied state. One of the most detrimental consequences of liquefaction is the reconsolidation volumetric settlements after the earthquakes, which is due to the dissipation of excess pore pressure caused by earthquakes. Severe floods can follow these settlements in free fields such as grounds

In this article the seismic site response of the Norcia basin, Central Italy, has been analyzed using both 1D and 2D ground response numerical models. Period-dependent aggravation factors (PDAFs) quantifying the difference between 2D and 1D site response are provided for two representative cross-sections of the basin. Time-domain linear visco-elastic and non-linear analyses were carried out by the

Slope instability and failure frequently occur in areas near faults. A series of shaking table model tests were conducted to examine dynamic response of slopes to near-fault ground motion in the time and frequency domains. Effects of the intensity and pulse characteristics of near-fault ground motions on slope response were examined. Test results show that peak ground acceleration (PGA) induced by

Initial static deviatoric stress can affect the liquefaction behaviour and deformation characteristics of saturated sand under cyclic loading. A series of cyclic triaxial tests were performed on a saturated sand consolidated under a constant vertical stress but different lateral stresses. The dependence of failure mechanism, liquefaction resistance, and stiffness evolution of the sand on initial static

This paper investigated the use of tuned inerter damper (TID) to enhance the seismic performance of dual isolated structure (DIS). An optimization design strategy was developed based on the performance requirements and expressed as a constrained multi-objective optimization design problem, where by the displacement response ratios of isolation layers were adopted as the constraints, and the acceleration

Stability prediction is a key step to implement a real-time hybrid simulation (RTHS) testing successfully. There are two kinds of stability prediction methods based on continuous and discrete transfer function. In the family of continuous transfer function based methods, the numerical and physical substructures are seen as continuous systems together with loading system. In discrete family, all subsystems

In order to meet the requirements of shake tables, frequency filtration of seismic input is usually performed before tests. Aiming to study the error of seismic analysis caused by filtering, the artificial seismic waves before and after filtering with four different waveforms were synthesized in this paper. Based on a spring-friction isolation system, the effects of filtering on seismic responses with

In this study, strong ground motion records were decomposed by wavelet transform using denoising and downsampling methods. To evaluate the changes in the frequency content of earthquake records during wavelet-based decomposition process, the vmax/amax values of the main and decomposed records were compared. According to the results, decomposition gives reasonable outcomes up to the third level. The

In performance-based earthquake engineering, simulated earthquake ground motions are often generated for time history analyses of structures and geotechnical systems. Liquefaction refers to dramatic loss of stiffness and strength of soils during earthquake shaking. As a complicated nonlinear process associated with accumulation of excessive pore pressure and decrease of effective stress due to soil-fluid

This paper investigates the axial load transfer during seismic events for pile groups installed in loose and dense sand layers. The analysis was conducted employing three-dimensional (3D) nonlinear finite element models (FEM) that were validated using the results from shaking table tests of a model superstructure supported by a pile group installed in saturated (liquefiable) and dry (non-liquefiable)

A constitutive model is developed for the ground response analysis of layered sites. The model is a one-dimensional version of Ta-Ger (2016) and involves critical state compatibility, anisotropic plastic flow rule and Bouc-Wen type hardening law. After being downgraded to the p-q stress space the model is reformulated to provide a unified framework of analysis for both drained and undrained loading

In this paper we present the results of a seismic experiment using data produced by an active Vibroseis source and varying the drive force level, during a standard seismic reflection survey. We observed a clear non-linear response that can be linked to the presence of shallow soft sediment layers. The variation of the applied vibration force induces a change in both propagation velocity and attenuation

A series of parametric analyses are conducted to investigate the combined effects of impact and structure-soil-structure interaction on a pair of closely spaced buildings in response to near-fault forward-directivity and fling-step pulses. The soil-buildings system is simplified into a discrete spring-mass-dashpot model, and ground motions are simulated using simple mathematical pulses, which enables

The study focuses on both the effects of soil foundation liquefaction on the induced damage of an embankment and on the generation of a probabilistic seismic demand model that relates few specific characteristics of seismic hazard at a site with the liquefaction-induced settlement. To this aim, several non-linear dynamic Finite Element (FE) analyses were performed. However, given the costly evaluation

Seismic failure mechanism of underground frame structures presents that the collapse of underground structures attributes to the insufficient seismic resistance of central columns. Therefore, researches have been conducted to improve the seismic performance of underground structures by enhancing the loading-carrying capacity of the central columns or decreasing the seismic loads transmitted to central

Void defects directly affect the dynamic response of tunnels. These defects have been recognised as an important factor that exacerbates seismic damage and the destruction of tunnel linings. Existing studies that consider the tunnel-void dynamic interaction use deterministic analysis methods, but they lack a quantitative analysis based on a probability method, which can reflect the random nature of

Engineers often use semiempirical models, which estimate the amount of seismically-induced slope displacements (D), to evaluate the seismic performance of earth structures and natural slopes. These procedures often use as inputs slope properties, earthquake parameters, and ground motion intensity measures (IMs). In this study, we propose a new set of machine learning (ML) based models to estimate D

The first cyclic simple shear tests on high-quality retrieved specimens of Christchurch silty and sandy soil were performed to evaluate their liquefaction potential. The test specimens originate from stratified silty soil deposits in southwestern Christchurch which did not typically have surface manifestations of liquefaction after the intense shaking of the 2011 Christchurch earthquake. The soil's

A large scale quasi-static test of reinforced concrete core wall with embedded steel frame (SFRC) under bidirectional loading was conducted to study the spatial failure mechanism systematically. The coupled shear wall and the single limb shear wall were respectively set in two directions of the specimen to reflect the effect of coupling beams. Subsequently, numerical simulation was adopted for parametric

This study builds on previous site-specific hazard studies for North Iceland, specifically regarding delineation of seismic sources and seismicity parameters. Using a Monte Carlo approach to generate synthetic earthquake catalogues for North Iceland, and multiple ground motion models (GMMs) that have been proposed and used for probabilistic seismic hazard analysis (PSHA) in Iceland in the past, the

Ground motion record selection methodologies are commonly developed to ensure that the input excitation used in response history analyses embodies essential conditions such as spectral compatibility, hazard and intensity measure consistency, seismological and site-specific criteria, always performing in a computationally efficient manner. A methodology utilizing genetic algorithms is revisited here

Crossing active faults has proven to cause significant damage in tunnels. In this study, a large–scale plate thrust model stimulating the LongMenShan Fault (LMSF) dislocation was established numerically. The characteristic dislocation curve of the fault generated at the stick-slip incidence was derived. Furthermore, a soil-structure FE model was established with a tunnel structure crossing the LMSF

Historic buildings and cultural relics are valuable and must be preserved carefully. However, such structures may be destroyed during earthquakes owing to the deterioration of their structural performance over time. Therefore, retrofitting protection measures must be adopted. The typical structural style of ancient buildings in China and East Asia involves timber structures. Due to the diversity of

According to the dramatic increase in construction near loose coastal saturated soils, stabilizing these soils due to saturation conditions has always faced challenges. The main purpose of this investigation is to assess the static and dynamic performance of saturated sand stabilized with polyvinyl acetate powder - as a newly introduced source of polymers which besides helping vegetation grow, owing

The technical note investigates the tensile force-displacement response of the hysteretic steel yielding brace known as Crescent Shaped Brace and characterized by a boomerang-like geometrical shape. The force-displacement curve is governed by three key performance points which correspond to the transition points separating the initial elastic behaviour, the flexural plastic behaviour, the geometrical

Liquefaction of foundation soil causes significant damage to infrastructures. The sand compaction pile (SCP) method is a countermeasure against liquefaction to densify the ground by installing dense sand piles. In recent years, an innovative method has been developed to install sand piles into the ground at any angle. In this study, a series of dynamic centrifuge tests are carried out to investigate

Herein, analytical and experimental investigations are conducted to characterize the performance of a novel variable friction pendulum bearing (VFPB) capable of progressively exhibiting different hysteretic properties for different displacement amplitudes. An analytic scheme comprising existing nonlinear elements is proposed, which can be easily implemented using currently available analysis software

The Gulf of Aqaba Dead Sea Transform fault (DSTF) is a plate boundary. Its southern section separates Sinai Peninsula, Egypt and Saudi Arabia. Also, it passes through several countries. A development plan with a huge budget is drawn to develop the Gulf of Aqaba region. This plan includes the construction of King Salman Bridge. Therefore, the assessment of the seismic hazard (SH) at this seismically

The effectiveness of remedial measures for the stability of onshore buried pipelines against the uplift mechanism induced by soil liquefaction, in the event of an earthquake, is investigated through 1-g shaking table tests. This study aims at proposing mitigation solutions that may be an alternative to the already existing and currently adopted systems, accounting for a set of requirements that cannot

Under seismic conditions a bridge abutment can transfer significant inertial effects to the superstructure due to its interaction with a large volume of soil. These effects can lead to a marked dynamic amplification of the abutment response that should be accounted for in bridge design. In order to quantify these effects, we present analytical solutions for the modal characteristics of the soil-abutment

The conventional Incremental Dynamic Analysis (IDA) used to evaluate the seismic response of structures, involves a series of nonlinear dynamic analyses, which requires extensive computational time and effort. This technical note utilizes a computationally efficient method to estimate IDA curves using Strength Variation (SV) curves. The accuracy of the proposed method is verified through comparisons

To implement the energy-based seismic design, it is important to quantify the energy dissipation within a structure. This paper evaluates the hysteretic energy demand (EH) within self-centering concrete frames (SCCF) with hybrid joints. Twelve SCCFs with different stories and self-centering parameters λ were designed. Two-dimensional analytical models were developed in OpenSees and subjected to forty-four

Quantifying the seismic fragility, risk, and resilience of structures is a computationally demanding step in the performance-based earthquake engineering framework as it commonly requires a large number of nonlinear dynamic analyses. The Endurance Time Method (ETM), which leverages just a small number of intensifying dynamic loads to obtain full responses of structures from elastic to collapse, has

The present work studies the combined in-plane (IP) and out-of-plane (OOP) collapse of unreinforced masonry infills (MIs) of strategic infrastructures such as hospitals retrofitted by hysteretic damped braces (HYDBs), where immediate occupancy (IO) and structural safety (SS, e.g. life-safety or collapse prevention) are the performance levels required after low-to-high amplitude earthquakes. Despite

The prediction equation of various construction induced ground vibration have been documented in the literature. However, no research is available in the literature to model the vibroflotation induced vibration. The major objective of this paper is to propose a methodology to predict the vibroflotation induced free-field ground vibration using large recorded data. The major contribution of this work

Retrofit of existing bridges founded on pile groups can be a challenging, costly, and time-consuming operation, especially when foundation interventions are required. The optimization of retrofit design, and hence of such complicated interventions, may be done by allowing controlled strongly nonlinear response of pile groups and associated energy dissipation mechanisms to develop during seismic loading

In this study, the pore water pressure accumulation laws in sand reinforced with randomly distributed fibers was investigated through cyclic triaxial compression tests. The effects of relative density, cyclic stress ratio, fiber content, and fiber length were examined. The test results showed that reinforcing the sand with randomly distributed fibers effectively delayed the pore water pressure accumulation

Numerous researches were conducted to explore the response of a pipe or tunnel to fault-induced deformation, most of which concentrated on strain distribution and failure mechanism. In this study, both centrifuge and numerical modeling are performed to investigate the active lengths of stainless steel pipes and concrete tunnels subjected to reverse faulting. The active length is assumed as the part

Steel plate-reinforced concrete (SPRC) coupling beams, in the form of a reinforced concrete (RC) beam with one (or more) internally embedded steel plate, have become a promising alternative in concrete coupling beam design. While existing studies have been carried out to demonstrate the favorable seismic performance of SPRC coupling beams, the effects of various factors on the seismic behavior of such

Earthquake ground motions (GMs) may display distinct characteristics in all directions within the horizontal plane. However, the causes of GM polarization are still not fully understood. Structural designs use maximum rotated intensity measures (IMRotD100) to accommodate variations of the GM with orientation, but the orientation associated with IMRotD100, β, is not easily predictable. This study investigates

Extraction of Rayleigh waves from earthquake signals has become an important topic in civil engineering and seismology. In this study, we propose an automatic filtering procedure to extract retrograde and prograde Rayleigh waves and their propagation azimuths from the earthquake signals, separately. In this method, the users do not need to specify an initial filtering limits. The proposed procedure