Propagation of long-period ground motion in sedimentary basins has been a subject of great interest among seismologists and engineers. Intense long-period ground motions consist primarily of surface waves that get trapped or generated locally as seismic energy travels through sedimentary deposits. In the present work, we investigate the propagation of surface waves in the basins of Kanto and Nobi in

During an earthquake, soil deposits are often subjected to complex stress/strain time histories that are quite different from the simplified ones used in laboratory tests for evaluation of the stress-strain-strength of these soils. To mimic the stress/strain time histories experienced at different depths of a mildly sloping soil deposit, a series of direct simple shear tests were conducted on Ottawa

This paper presents results from geotechnical centrifuge tests performed at the Japanese Institute of Occupational Safety and Health (JNIOSH) in Tokyo, Japan. A range of shallow footing configurations with different bearing pressures founded on saturated sand in a laminar box on a shake table was studied using harmonic excitations. The free-field condition was also studied as a reference. The study

In order to reduce the displacement demand of the isolation layer under strong earthquakes, especially strong near fault pulse-like ground motions, the base isolation system-tuned mass damper inerter (BIS-TMDI) system is explored taking the nonlinear hysteretic characteristics of the isolation layer into inclusion. Likewise, different from traditional layout of the BIS-TMDI systems, the TMD is placed

Bender elements are shear wave transducers, used for the computation of small strain shear moduli of geomaterials. However, the distortion of the output signal caused by residual compression waves may lead to important errors in the shear modulus estimates. We present a novel procedure for the optimisation of the location of the receiver bender element, to avoid regions where the distortion of the

A new method for predicting inelastic displacements of reinforced concrete moment resisting frames under seismic motions is presented. The method uses modal behavior (or strength reduction) factors for the first few significant modes, which are functions of period, interstorey drift ratio, plastic rotation, performance level and soil type. Explicit empirical expressions for these factors have been

The mechanical behaviours of soft clays under cyclic loading are not only related to loading parameters, but also the physical indices of soft clay. One-way cyclic triaxial tests with constant confining pressure were adopted, however, the stress field induced by traffic loads includes cyclic confining pressure and cyclic deviator stress. So far, the damping ratio evolution of soft clays under traffic

Dry and moist tamping methods are widely used for the investigation of sandy soil liquefaction. However, the effect of these two tamping-based reconstitution methods on composite soil liquefaction behavior have been rarely assessed. In this study, the dry and moist tamping methods were assessed using loose silica sand matrix (HN31) containing various amounts of non-plastic silt particles (C500), and

Deep dynamic site characterization was conducted at the Central United States Seismic Observatory (CUSSO), which is a 587 m deep vertical seismic array situated in the Mississippi embayment. This characterization included a combination of active and passive source surface wave methods and horizontal to vertical spectral ratio (HVSR). These measurements were used in a multimodal joint inversion of Rayleigh

Assessing the dynamic stability of earth slopes is an important topic in geotechnical engineering field. In this study, the duration effect on the seismic performance of a multi-layer earth slope is quantitatively investigated, using two pairs of ground-motion suites selected matching a scenario-based response spectrum and a design spectrum, respectively. The four ground-motion suites are selected

A 1/70-scale soil-pile-bridge model was designed and constructed according to an extremely long-span cable-stayed bridge with a 1400 m-main span. Shaking table tests were performed to estimate the effects of the near-fault earthquake waves on the seismic responses and pile-soil interactions of the bridge model under near-fault and far-field earthquake waves in the longitudinal direction. A three-dimensional

In-situ soil deposits often have an initial shear stress that significantly affects their subsequent cyclic behavior and liquefaction susceptibility. This is closely related to the internal structure of the soil but is very difficult to study thoroughly through conventional laboratory tests. In this study, a numerical procedure that can impose arbitrary two-dimensional stress or strain paths was developed

A rocking steel frame with buckling-restrained braces (RSFB) with excellent deformation controlling and energy dissipating capacities is proposed to retrofit conventional steel frames. Notably, previous studies have shown that the seismic performance of structures with buckling-restrained braces (BRBs) was influenced by the connection forms of the BRBs within the structures. In this study, a series

Screw micropile is a new type of steel pipe pile that consists of a smooth, threaded segment and a tapered segment. It is installed using the torque method. To examine the axial cyclic behavior of the piles, six one-way compressive and load-controlled axial cyclic tests were performed at a sandpit site. The axial cyclic load, with 15 cycles and an equivalent peak vertical acceleration ranging from

This article proposes an efficient procedure for the probabilistic seismic analysis of slopes and applies it to two slope examples including a real engineering project. The proposed procedure evaluates the stability condition of a non-homogeneous slope by using a discretization kinematic approach (DKA), and accounts for the time and space variations of a seismic loading by employing pseudo-dynamic

Triple friction pendulum isolation bearings are typically designed with only earthquakes in mind, or perhaps with a large enough initial friction coefficient to limit displacement under wind loads. However, for potential application in high-rise buildings, wind demand is of greater concern, and the increased flexibility of the structure can lead to wind-induced floor accelerations that exceed the serviceability

With mining depth increasing, the mining structure becomes more and more complex. It is easy to cause dynamic disaster during coal mining. To reveal the failure process of gas-bearing coal at complex mining environment, the dynamics experiments were conducted through Split Hopkinson Pressure Bar of gas-bearing coal (SHPB-GAS) experimental system. The results showed that the filtered stress waveform

Three shaking table tests were carried out to investigate the influence of loading frequency on seismic performance of MSE walls constructed with full-height panel facing. Results of this study provide quantitative results on how base excitation frequency in combination with base acceleration amplitude could influence the dynamic response of these MSE walls relative to their deformations, earth pressures

An analytical solution to the scattering of plane P and SV waves by a composite lining tunnel with imperfect interfaces in full space is presented using the wavefunction expansion method. The spring model is introduced to depict the imperfect interfaces among the surrounding rock, primary support, isolation layer and final lining of the tunnel. The influences of incident wave types, interface spring

The dynamic mechanical properties and fracture process of rock materials with pre-existing flaws are crucial for explaining the failure mechanisms of deeply buried constructions. To investigate the mechanical properties and fracture behavior of flawed granite subjected to dynamic loading, dynamic experiments were conducted on granite specimens by using a split-Hopkinson pressure bar test system. The

Rectangular closed diaphragm walls (RCDW) has recently been used as a new type of liquefaction mitigation foundation; however, the mechanisms of liquefaction mitigation have scarcely been studied. This paper proposes a 3D nonlinear solid-fluid fully coupled effective stress numerical model in the OpenSees software to study the liquefaction mitigation mechanisms of RCDW. Data from centrifuge tests of

Large stock of scrap tyres in waste disposal ground is a huge threat to the environment. In many civil engineering applications, potential of using scrap tyres have been explored in the last two decades. In this paper, effectiveness of Un-bonded Scrap Tyre Isolator (U-STI), as a seismic isolation system, has been evaluated by both experimental and numerical studies. Simple design approach of low-cost

This paper investigates the combined effect of the vertical component of the input motion and of the weakening effect associated to pore-pressure build-up with reference to a zoned earth dam for which the most recent probabilistic seismic hazard analyses promoted the need of evaluating its seismic performance. The two effects were studied through advanced plane-strain non-linear dynamic analyses using

Reduced-scale centrifuge experiments are widely used to simulate complex boundary-value geotechnical problems and to validate numerical or analytical models. The recordings obtained from these experiments can also help researchers back-calculate soil properties, which are subsequently used in model analysis. In this paper, we investigate how the container boundaries and scaling at different levels

Seismic microzonation maps for Guwahati metropolitan area are presented based on the Uniform-Hazard-Spectrum (UHS) methodology. UHS method satisfies the performance-based design (PBD) criteria, which are based on two sets of spectral amplitudes, one for which the structure will remain linear, and the other for which it may undergo nonlinear response. The UHS method also considers contributions from

Near-field records with long-period velocity pulses can be considered as a most important factor in causing structural damage. In order to understand the effects of near-field records on the seismic behavior of a 2.0 MW land-based wind turbine, a 1/20-scaled model is designed and investigated by shaking table test. Two pulse-type near-field records (Westmorland record, Chi-Chi record) and two far-field

Pile-supported wharves, as one of the main components in marine harbor systems, are subjected to multiple hazards such as earthquakes and corrosion during their lifetime. In this paper, the corrosion initiation time due to chloride ion diffusion (using both the deterministic and probabilistic approaches), temperature and humidity variations are calculated for various steel materials in the typical

This work focuses on site response analyses in the Amatrice area (Central Italy), taking advantage of the 3A temporary seismic network, installed after the first shock (MW 6.0) of the 2016–2017 seismic sequence, and of a detailed site characterization. Classical empirical methods are applied on seismic signals to evaluate their capabilities to infer site response parameters. For about one-third of

Lightweight expanded clay aggregate (LECA) is a geomaterial that is low in density, porous, and has an enamel surface. A series of unconfined compression and resonant column tests were performed to understand the dynamic performance of LECA. Testing results show that the uncemented LECA is poorly graded but possesses a stable internal structure. The initial shear modulus, shear modulus reduction, and

The void ratio limits and their range are mostly governed by their grain size, distribution, particle shape and fabric for cohesionless soils. For the purpose of developing a probability-based predictive model, a database, which consists of minimum and maximum void ratios, their range, as well as particle morphology (roundness, sphericity), size and distribution (mean grain size, fines content and

In practical engineering, the pile foundation is often subjected to lateral load while bearing vertical load. And the lateral and vertical bearing capacity of pile generally are calculated separately during the design of pile, without considering the effect of existing vertical load on the lateral capacity of pile. Based on the theory of elastic foundation beam, the stress in the pile units of laterally

The 2.5D dynamic response of a half-space to an internal point load moving at sub- and super-critical speeds is studied in Cartesian coordinates both analytically and numerically. Firstly, the partial differential equations of waves are converted to the ordinary differential equations by the Fourier transformation. Then, a multiplying factor is derived and added to the stiffness matrix to account for

In this paper, the seismic performance of a reinforced concrete (RC)-framed underground subway station structure which has three stories and three spans was analyzed firstly under strong earthquakes. It was found that the central columns in the top and the bottom stories were the weakest seismic components in this type of underground structure. Thus, lead-core rubber bearings (LRBs) were installed

There is a need for benchmarking and validating simulated ground motions in order for them to be utilized by the engineering community. Such validation may be geared towards a specific ground motion simulation method, a target engineering application, and a specific location; the validation presented herein focuses on a bridge engineering application in southern California. Catalogs of simulated ground

Prototype and physical scale numerical models were created using OpenSees to simulate centrifuge experiments representing a sloping ground condition in accordance with LEAP-Asia-2019 guidelines. The PM4Sand constitutive model calibrated for Ottawa F65 sand was used. Simulated results showed reasonable agreement between prototype and physical centrifuge test scale models. Modeling fundamental characteristics

The cross-section and the structural twist angle of a typical wind turbine blade vary along its span. This complicates its realistic modeling in nonlinear dynamic analysis of wind turbines when seismic performance estimates are sought. As a result, the lumped mass approach is most commonly used to model the rotor-nacelle-assembly (RNA). The RNA is eccentric to the tower top, and the blades tend to

This paper presents experimental results from shaking table tests on two reduced-scale geogrid reinforced soil retaining wall (RSRW) constructed using standard soil, modular facing blocks, and uniaxial geogrid reinforcement to investigate the distribution of the lateral displacement, observe the failure mode of the RSRW, and analyse the lateral displacement control index under seismic loading. Similitude

A series of cyclic direct simple shear tests are performed to investigate the liquefaction resistance of sandy soils from Christchurch, New Zealand. The study focuses on the combined effects of soil density and fines content on liquefaction resistance of sandy soils. Two sands, a non-plastic silt, and their mixtures prepared at different fines contents are tested at two sets of relative densities.

“Basin effects” refers to trapped and reverberating earthquake waves in soft sedimentary deposits overlying convex depressions of the basement bedrock, which significantly alter frequency content, amplitude, and duration of seismic waves. This has played an important role on shaking duration and intensity in past earthquakes such as the Mw 8.0 1985 Michoa'can, Mexico, Mw 6.9 1995 Kobe, Japan, and Mw

For the monopile-supported offshore wind turbine (OWT), scour can significantly affect the seismic responses of the structure. However, the combined effects of scour and earthquakes are not fully appreciated. This study proposed a new method to evaluate the post-scour seismic responses of monopole-supported OWTs, considering various scour-hole dimensions and soil stress-history changes due to different

In this paper, a method for generating samples of a fully non-stationary zero-mean Gaussian process, having a target acceleration time-history as one of its own samples, is presented. The proposed method requires the following steps: i) divide the time axis of the target accelerogram in contiguous time intervals in which a uniformly modulated process is introduced as the product of a deterministic

The present paper articulates a mathematical model for the propagation of horizontally polarised shear (SH) wave in an initially stressed composite layered structure under the influence of an impulsive line source. The initially stressed composite structure is comprised of a transversely isotropic fluid saturated porous layer over a foundation with dry sandy elastic stratum and functionally graded

Cushioned pile-raft foundation (Cushioned-PR) is a new type of foundation for sea-crossing bridges in deep water (more than 50 m in depth). Cushioned-PR is able to tolerate a certain amount of slide that occurs between the raft and the piles under strong earthquakes. This characteristic could reduce the seismic motion transmitted to the superstructure to maintain the integrity of the bridge. Thus,

On automatic block lines, there is a time interval between two trains traveling on a track in the same direction. Therefore, the dynamic load on the railway subgrade is composed of the periodic vibrations generated when the train passes, and the intermittent period when there is no train passing. To study the influence of the train interval time on the dynamic behavior of a railway subgrade, a series

In this paper, the utility of power spectral density (PSD) in ground motion prediction for hazard analysis is examined. The main advantage of PSD is that the area under PSD of excitation gives the energy of the excitation and it is structure independent. The PSD of ground motion from past earthquakes and properties of PSD in terms of spectral moments are studied. 1487 accelerograms from 25 major past

The damped outrigger system, an improvement of the conventional outrigger system, can contribute to better vibration control in high-rise buildings through proper supplemental damping. Using a spectrum-analysis-based simplified model, the optimal seismic performance of single-viscous damper-outrigger system is investigated in this study. This simplified model is first calibrated by an ANSYS model via

Temporary seismic frequency wandering of buildings during and after seismic events has often been observed and has not yet been investigated, in particular with regards to the effects of the pore pressures generated within the soil mass. This paper investigates the influence of delayed soil response on the observed temporary natural frequency wandering induced by seismic actions. The focus is on the

In the shaking table tests of underground structures, the scale ratios of the soil and structure are inconsistent. To this end, a scaled model soil was developed in this study. Through a series of tests, the dynamic response of the model soil was investigated. A clay mixed with sawdust was designed for shaking table tests based on the predominant period similarity relationship between the structure

This study investigates the deformation properties of recycled concrete aggregate (RCA) when blended with up to 70% of recycled glass (RG) for pavement base applications. A multi-stage repeated load triaxial (RLT) testing procedure was proposed and utilized for evaluating the permanent deformation behavior of RCA/RG blends. The resilient modulus (Mr) of the blends was examined by performing RLT test

The more accurate prediction of the seismic input energy spectrum contributes to a more efficient energy-based design and seismic assessment. This study presents a model to estimate the inelastic seismic input energy imposed on structures, employing a wide range of ground shaking and structural features. In this regard, the pseudo-velocity spectrum and the proposed Scaled Energy Index (SEI) are utilized

Seismicity related to industrial mining activities needs to be understood and quantified in order to ensure safe mining operations. It is of great important to determine if the sources of such events follow the common models and theories, and determine the source rupture property and scale of such events. Moreover, the location of the source is very important to obtain the source parameters. For this

We revisit previous results in small-strain One-dimensional Site Response Analysis of heterogeneous soil deposits. Specifically, we focus on sites whose shear modulus distribution is described by means of a power law that yields zero stiffness at the free surface. First, we show that in some cases (which we characterize in detail) considerations of energy finitude should prevail over considerations

The realistic simulation of the train dynamic loading is essential to the study of the dynamic behaviors and long-term stability of the railway subgrade. Considering the loading intermittence caused by the time interval between adjacent trains and the increasing dynamic stress response of the subgrade caused by the increasing axle load and running speed of trains, a series of dynamic triaxial tests

Large-scale E-Defense shaking table tests were performed using a 3 × 3 pile group in dry sand layers to clarify dynamic lateral pile behavior in a group. The mechanism behind the seismic response of piles in a group was investigated based on the earth pressure acting on piles and soil deformation in the vicinity of the pile and that in the free field. The test results indicated that soil deformation

This study investigated the effect of foundation type and layout on the seismic vulnerability of tall reinforced concrete buildings using fragility curves. To this end, the seismic fragility of 12-, 18-, and 24-story buildings sitting on shallow and pile foundations (i.e., with rigid and flexible pile caps) were evaluated. The uncertainty in the structural and soil properties was assessed by using

Numerous highway bridges have been constructed with slender tall piers over 40 m in Southwest China, due to the mountainous topography. Current researches on this type of bridges mainly focus on the higher mode effects on the seismic behavior of pier columns, while the responses of group pile foundations are generally neglected. The objective of this paper is to investigate how the dynamic demand of

During the past two decades, many emerging smart lateral force-resisting systems have been proposed for achieving better post-earthquake recoverability than the conventional ones in steel buildings. The Self-centering Energy-absorbing Dual Rocking Core (SEDRC) system has been developed recently by the authors for achieving excellent self-centering behavior with large deformability in steel buildings

The paper presents and discusses the dynamic foundation impedance functions calculated from full-scale field tests on soil-structure interaction at the prototype facility of EuroProteas at Euroseistest in Greece. The experimental campaign included ambient noise, free- and forced-vibration tests throughout a wide frequency and amplitude range. The response of the soil-structure system was observed to

Traditional bilinear hysteretic dampers (BHDs) are installed in buildings to enhance their seismic performance by increasing the effective stiffness and damping and are usually designed to guarantee the structural safety for severe ultimate limit state seismic events. As a negative consequence, only minimal damping is provided during weak but more frequent serviceability limit state earthquakes since

The seismic failure mechanism of a shallow-buried prefabricated corrugated steel utility tunnel on the liquefiable ground was investigated by the shaking table test and numerical simulation. Firstly, A scaled model of prefabricated corrugated steel utility tunnel, inside pipelines, and three kinds of brackets were designed and fabricated. The model system was then excited by two seismic ground motions