This paper presents a new hybrid passive control device, consisting of a viscoelastic and a friction damper connected in parallel, to mitigate the effects of wind and seismic events. The two components are synergized with the aid of a novel locking mechanism, which enables the action of one or both the components depending upon the device deformation. This provides an innovative two-phase energy dissipation

The method of incremental dynamic analysis (IDA) is one of the most accurate nonlinear seismic analyses. IDA is a time-consuming method and has a high computational cost. Also, an IDA curve should be obtained from the building analysis subjected to a series of earthquakes that should cover all regions of the structural responses. In this paper, the discrete wavelet transform is used to solve these

A novel integrated precast concrete (PC) structural system, which maximizes instead of minimizing the interaction between the PC sandwich cladding panel and main structure, is proposed through the introduction of U-shaped dampers. To systematically validate the feasibility and reliability of this system, a full-scale PC wall-frame substructure equipped with an energy dissipation PC sandwich cladding

Seismic performance of postmainshock buildings considering seismic mainshock-aftershock sequences are studied. The case studies correspond to three SAC steel MRF buildings of three, nine and twenty stories. The 2-D models are able to capture important properties of deterioration of strength and stiffness. Endurance time method is used to predict the response of structures in different hazard levels

In regions of low-to-moderate seismicity where representative strong motion data is lacking, the modelling of seismic hazard relies on the use of seismological models. This paper presents a set of expressions that can be used as ground motion prediction equations that have been transformed from seismological models which resolve the generation of seismic waves into several components. The feature of

A weighted scaling method (WSM) is developed for the selection and modification of structure-specific earthquake records in time-history analysis. The matching errors and scaling factors are calculated by weighted least-squares method to match with target spectrum. The weight factors are determined by the modal-mass participation factors. The 3-, 9-, and 20-story steel moment-resisting frame structures

The 2017 M5.4 Pohang, South Korea, earthquake damaged numerous buildings. Immediately after the main shock event, 1,880 professional engineers inspected the damaged buildings and assigned three damage grades (“Usable,” “Restricted use,” and “Unusable”). We investigate factors influencing the building damage. The built year, number of stories, and estimated peak ground acceleration are strongly related

In this paper, the problem of dynamic stress concentration in the process of anti-plane motion caused by a single circular cavity in a strip medium and the non-circular cavity in a porous strip medium is studied. In the case of only a single circular cavity, a numerical calculating example is presented to solve scattering around a circular cavity with a given SH guided wave and describe dynamic stress

Assessment of liquefiable soils strength is a challenging task in engineering practice especially when a structure is founded on top of the liquefied soil. While it has been addressed and studied in the literature, the lack of practically feasible approaches to calculate the bearing capacity of soil in such a condition is tangible. In this study, simple analytical equations have been proposed to calculate

Structure-canyon-structure interaction is investigated using a whole model of two shear walls supported by rigid foundations on both sides of a semi-circle river-canyon embedded in a homogenous half-space. A closed-form analytical solution is presented for the model response to incident plane SH-wave based on the wave function expansion method. The analysis focuses on the effects of the structure-canyon-structure

A hybrid force/displacement (HFD) performance-based seismic design method is proposed for two types of plane reinforced concrete structures, i.e., infilled moment-resisting frames (I-MRFs) and wall-frame dual systems (WFDS). The HFD seismic design method is a force-based method which controls with high accuracy both structural and non-structural deformation limits. The behavior factor is related here

This study introduced a new design of the grouted corrugated duct connection (GCDC), which improves the structure integrity, bond strength and ease of constructability. A two-phase experimental program was performed to fully understand the connection behaviour. Phase I focused on the pull-out tests of 32 specimens in two batches with various conditions. It indicates that a connection length of 30 times

To assess the dynamic stiffness of shallow foundations, as an alternative to the existing rigorous approaches, it is convenient to idealize the soil as some semifinite truncated cones representing the infinite nature of the supporting soil. The one-dimensional wave equation for cones which is usually defined in frequency domain has been extended to be solved directly in the time domain. The recently

Newmark analyses of lateral spreading induced by liquefaction were conducted using a database of 22 documented case histories. Site stratigraphy and SPT values for the liquefiable soil were based upon the case-history documentation. The yield acceleration was estimated based on post-liquefaction residual shear strength estimated using three different correlations with SPT blow count. Representative

Under near-field ground motions, fluid viscous dampers (FVDs) are effective in controlling deck longitudinal displacement but lead to the increase of bending moment and shear force at tower base. Negative stiffness (NS) devices are introduced in combination of FVDs for the bridge. The NS devices lengthen the fundamental vibration period of the bridge to reduce the spectrum acceleration whereas FVDs

In timber structures, connections traditionally provide ductility and energy dissipation under seismic loading. Capacity design ensures that the global structural response is ductile by applying overstrength to the design demand of brittle elements. Overstrength is often derived experimentally which is costly and time-consuming. This paper proposes an analytical method to estimate the overstrength

In removal and replacement technique, yielded hoops from the damaged joint core are not removed for practical difficulties, and it remains inside the joint core after rehabilitation. An attempt has been made in the present article to study the effect of yielding of hoops on cyclic performance of seismically detailed beam-column joint. It was observed that in case of specimens with pre-yielded hoops

A new experimental apparatus for performing impact tests is presented, to analyse the wave propagation phenomenon in pure sand and in composite sand-polyurethane specimens, with the final aim to explore the seismic mitigation given by a polyurethane inserted into a real soil under existing structures. Polyurethane layers at three different thicknesses are considered. Experimental results show that

In this study is investigated the performance of different glass fibre-reinforced polymer strengthening schemes on infilled reinforced concrete (RC) frames. The main objective was to limit the damage to beam–column joints and inter-storey drift ratios and to protect RC frames against the negative effects caused by infill-RC frame interaction. Five specimens were tested: one without infill and four

An all-steel bamboo-shaped energy dissipater (SBED) composed of a bamboo-shaped core and a buckling-restrained tube was recently proposed. However, systematic parametric studies on the effect of experimental parameters of SBED have not yet formed, as well as design method. In this paper, the numerical model established for SBED was firstly calibrated based on previous test results. Then, five series

A method for the estimation of expected annual losses under seismic action, using a component-level approach, is proposed. The method follows the general steps of current Performance-Based Earthquake Engineering approaches and two distinct alternatives are evaluated depending on how the collapse cases are identified. Results are compared with a commonly implemented structure level approach, showing

In this paper, reliquefaction studies of saturated sand deposits prepared at 40% and 60% relative density were tested using a uni-axial shaking table at repeated incremental acceleration loading conditions. The repeated acceleration loading was selected similar to continuous earthquake and associated foreshock/aftershock shaking events observed in recent earthquakes. For experimental testing, sinusoidal

The inerter-based systems have proven to be effective for vibration control of adjacent structures. The interaction through the soil medium between adjacent structures in urban areas is generally accepted. However, existing studies concerning the inerter-based adjacent structures are primarily based on the assumption of a fixed base, without considering the inevitable interaction. To address this issue

Strength hierarchy assessment method is a capacity analysis procedure that can be used to identify the sequence of failures likely to occur within reinforced concrete (RC) frame buildings under lateral actions such as earthquakes or wind loads. Previous publication on this method mainly focused on the application of this method to (a) the vulnerable RC beam-column joints without any joint shear reinforcement

A major limitation with conventional post-tensioned (PT) shear wall in seismic areas is its low energy dissipation, which is tackled by placing additional mild steel reinforcement at the intersection of the wall and the foundation, called internal energy dissipating reinforcement (EDR). While the behavior of hybrid walls with internal EDR is satisfactory, the replacement of them post-yielding (i.e

Existing Ground Motion Prediction Equations (GMPE) in practice for North East India have been developed using limited or simulated datasets of recorded ground motions. The current study presents the development of a new GMPE based on a well-established model considering actual recorded ground motion data comprising of acceleration, magnitude, and hypocentral distances. A larger dataset with magnitudes

High-Damping Natural Rubber (HDNR) bearings are widely employed for seismic isolation. These bearings are characterized by a remarkable nonlinear behaviour and often by a degrading cyclic response, induced by the addition of filler to enhance its dissipation capacity. This latter phenomenon, denoted as stress-softening or Mullins effect, can significantly influence the nonlinear dynamic response of

Prior studies, which have been limited to horizontal ground shaking, have generally concluded that soil–structure interaction (SSI) has a negligible influence on the seismic response of isolated buildings. In this study, the effect of SSI on the response of a computational model of an isolated building using triple friction pendulum bearings is investigated. The analysis shows that SSI can amplify

Many bridges in seismic prone regions suffer from serious foundation exposure caused by scouring of the riverbed. In this study, the seismic performance of a bridge at various scour depths is assessed using a nonlinear static procedure based on the capacity spectrum approach. The performance limit of the bridge is identified in the capacity spectrum. The level of seismic intensity, characterized as

Columns in building frame systems are subjected to the combined action of bidirectional horizontal loading and axial load variation during an earthquake. Whilst the behaviour of RC columns under unidirectional and bidirectional lateral loading with constant axial load is understood well, the behaviour under bidirectional lateral loading with axial load variation is rarely studied, especially for limited

The present work aims at exploring the application of nonlinear principal component analysis in dimensionality reduction and prediction of response spectra. The evaluation is performed based on log10 scaled response spectra at 91 spectral periods corresponding to 13552 records available in the NGA-West2 database. The non-linear principal component analysis performed on the data showed that 91 spectral

Four new kinds of corrugated metal dampers were designed to investigate the behavior of energy consumption. The experimental results show that the mild steel damper has a preferable seismic capability. In addition, the method of simulating weld failure is proposed through using the cohesive crack model, and the mild steel damper is analyzed from the views of weld failure. The recommended value of the

The deformation behavior of beam-column sub-assemblages has a significant impact on the lateral displacement of frame structures. Understanding and realistically predicting the deformation constitution of beam-column sub-assemblages are important aims in the control of frame structural lateral displacement. In this study, experimental tests on three reinforced concrete frame structures were carried

Buckling-restrained braces (BRBs) are commonly used as a kind of energy dissipator in structures, which can be quickly replaced after strong earthquakes. However, there is no reasonable and effective damage assessment method to quantitatively analyze the damage degree in a BRB. Since the cumulative plastic deformation (CPD) of a BRB is closely related to its loading history, the CPD can reflect the

Recent worldwide earthquakes have emphasized the severe damage potential of pulse-like ground motions caused by forward directivity close to a fault rupture. We investigate the effect of such directivity-induced pulse-like ground motions on the fracture fragility and fracture risk of pre-Northridge welded column splices (WCSs) in near-fault regions. To this aim, incremental dynamic analysis (IDA) is

Due to soil -structure-interaction (SSI), the seismic lateral structural deformations may be substantially different from the ones traditionally calculated from the fixed-base structure on free-field approach. Additionally, the actual displacements of foundations considering soil compliance are of practical interest in some applications. In the present study, seismic elastic displacement demand of

After the 2010 Maule earthquake, Chilean authorities now require the implementation of base isolation systems in new public hospital build-ings. However, in Chile the typical seismic force-resisting system of non-isolated hospitals is made up of reinforced concrete shear walls, whereas that of isolated buildings is made up of reinforced concrete frames. Since the former is much stiffer than the latter

Full-capacity large-scale liquefied natural gas (LNG) tanks comprise a steel inner tank and a concrete outer tank. The space between the walls of these two tanks is filled with expanded perlite and a resilient blanket as an insulation layer. It is well known that interactions between the outer tank, insulation, inner tank, and liquid occur under seismic loads. In this study, to investigate the effect

Sliding implant-magnetic bearing (IMB) is a new type of seismic isolators that benefits from its adaptive energy-dissipation behavior. In order to assess the performance of the sliding IMB for seismic protection, a complete shaking table test on the base-isolated structure is reported in the present paper. Tri-directional-recorded earthquake ground motions and mono-directional artificial earthquake

This paper presents an analytical solution to the ground motion of an isosceles hill with slope change under incident SH waves. A new partitioning method, multi-region-matching technique (MRMT), is proposed in this paper to establish an accurate analytical solution model. Based on the complex function method and multipolar coordinate transformation, the infinite algebraic equations are established

This study aims to estimate attenuation characteristics of the central Himalayan region of India concerning various strong-motion parameters such as Kappa value (κ) and site effects. We have tried to elaborate on the regional structural heterogeneities and their implications towards the seismic hazard assessment of the study region. A total of 81 earthquakes recorded at 50 stations situated in the

This paper presents a new structure, called a cassette structure, and the modified design method of its core vertical elements, called a grid frame wall, is proposed. The advantages, mechanical properties and performances of the original grid frame wall are introduced, and its weaknesses are discussed based on practical engineering buildings and cycling load tests. To improve the structural performance

A precast concrete frame with replaceable energy-dissipating connectors (REDC) is designed as an innovative system. The REDCs are placed at the top and the bottom of the beam-ends to dissipate energy during major earthquakes. A displacement spectrum-based design method is presented, which can directly determine the target period under strong earthquakes. The results of nonlinear time-history analysis

Site amplification coefficients and acceleration design response spectra (ADRS) for the shallow sites in SI are derived based on non-linear site response analysis at 125 locations. Input motions are selected by considering the seismic hazard map for 475 years as return period and inputted at depth where VS ≥ 1,500 m/s. The new site factors, i.e. FPGA, Fa, and Fv, are proposed for Southern India (SI)

This study aims to assess the seismic performance of typical reinforced concrete buildings constructed in Australia before the enforcement for seismic design. The response of both the primary lateral load resisting system and the gravity load resisting system is considered. A brief description of the modelling approaches adopted to simulate the response of the buildings’ components is provided. Nonlinear

A complicated natural topography, such as a cavity beneath a canyon, can cause considerable ground motion during earthquakes. This phenomenon is referred to as a site effect. An awareness of site effects can help to reduce damage to property and loss of life. However, modeling the highly complex interactions between a cavity and a canyon requires considerable mesh skills. In this study, we developed

The manufacturing of rubber bearing is complicated, the horizontal stiffness of the final product maybe greatly affected by the uncertainties during the processing, thus, it is necessary to study the distribution characteristics of the rubber bearings’ horizontal stiffness, and its influence on the seismic performance of the isolation structure. The rubber layer thickness was taken as a comprehensive

Corrosion represents one of the most important problems affecting the global behaviour of reinforced concrete (RC) buildings; in presence of aggressive environmental conditions reinforcing steel bars, as well as concrete, suffer from relevant modifications of the mechanical performance. Steel rebars show a high decrease of the deformation capacity, with reduction of the elongation to maximum load up

A vertical-to-horizontal (V/H) response spectral ratio of 2/3 is commonly adopted in earthquake engineering for assessing the magnitude of vertical motion. However, higher V/H ratios are found in some earthquake records. This study evaluates the factors that can influence the V/H ratio on the basis of vertical and horizontal site response analyses. Two sets of rock motions representing near-source

This paper investigates the potentials of inter-story isolation systems (IIS) for retrofitting irregular masonry buildings by means of an isolated vertical addition realised on the roof of the existing structure. By assuming a case study, a wide parametric analysis is firstly carried out on lumped-masses model for identifying the dynamic properties of the isolated superstructure that minimizes the

This study investigates the effect of torsional components of the ground motions (TGM) on the floor acceleration response of flexible special moment-resisting frame (SMRF) buildings. For this purpose, computational models of three SMRF buildings were subjected to far-field ground motions with and without TGMs. Accordingly, the effect of TGM on the floor acceleration of structures with relatively short

A parametric study is performed on the cyclic behavior of reinforced concrete connections. A number of 64 analytical cases are developed being different in the value of the axial force of column, volume of the transverse reinforcement in the connection, ratio of the bending capacity of column and beam, and the continuity index of the longitudinal bars of beam in the connection. The stiffness, dissipated

The main objective of this study is to assess the accuracy and suitability of Nonlinear Static Procedures (NSPs) in the development of analytical damage fragility curves for seismic risk assessment of large portfolios of Reinforced Concrete (RC) bridges. Seven NSP approaches, from widely used single-mode conventional pushover-based approaches to the more rigorous multi-mode conventional or adaptive

This paper focuses on the effects of near-fault motion characteristics on the seismic performance of tall pier bridges. Using the analytical models calibrated by shake table tests, fragility analysis was conducted investigating the influence of near-fault motion features (i.e., period (Tv) and number (N) of velocity pulses). Results show that seismic fragility of the tall pier under near-fault motions

We analyze the global and local uncertainties of ground motion-macroseismic intensity conversion equations and derive new probabilistic relationships between the macroseismic intensity and peak ground motion parameters (peak ground acceleration and peak ground velocity) for western China based on the assumption that the peak values of ground motion are randomly distributed for each MMI level, bounded

Thin reinforced concrete walls may fail due to out-of-plane instability when subjected to seismic loading. While previous numerical studies on wall instability have focused on the behaviour of members with two layers of vertical reinforcement, this work addresses the response of walls with a single layer of rebars. Such walls are particular prone to out-of-plane failure when subjected to cyclic in-plane

This manuscript quantifies the effects of aftershocks with pulse characteristics on the cumulative damage of structures. The revised randomization method is developed to generate the artificial mainshock-aftershock (MSAS) ground motions showing pulse characteristics. The efficiency of period normalization is discussed from the point of view of dispersion, and the effects of the aftershocks are quantitatively

In practice, elastic response spectra are generally obtained by utilizing the 5% value for the damping ratio. The Damping Reduction Factor (DRF) allows to account for higher damping values. As proved by many literature studies, the DRF mainly depends on the structural damping ratio, until now essentially treated in a deterministic way. In this framework, the main aim of the present study is to explore

The study presents a liquefaction potential analysis for the Thailand-Myanmar border area due to the earthquake. Three sites reported liquefaction during Tarlay earthquake in 2011 were investigated including a microtremor to obtain the shear wave velocity profile and depth of engineering bedrock. Next-generation attenuation model was used to estimate the peak ground acceleration at the liquefied sites

Within the European FP7 Project “INSYSME”, the research unit of the University of Pavia has developed a seismic-resistant masonry infill system with original details, which subdivides the masonry panel into horizontal stripes through the insertion of “sliding joints” and deformable joints at the infill–frame interface. The out-of-plane stability is governed by the flexural/arching resistance of the