ABSTRACT The velocity pulses produced by forward-directivity effects in the near-fault regions can have destructive effects on structures. Proper estimation of the duration of such velocity pulses is an essential step in the near-fault seismic hazard analysis and mitigating potential damage. In this study, the effects of different source, path, source-to-site geometry, and local site parameters on

ABSTRACT Seismic retrofitting of exiting building structures is a technical and social issue aimed as earthquake risk mitigation. In this study, a new technique for seismic retrofitting via the attachment of an external steel frame with length-adjustment control box (ESFLC) was developed to strengthen medium-to-low-rise reinforced concrete (RC) buildings. The developed method, categorized as a strength

ABSTRACT The performance of a new type of concrete columns reinforced with multi-tied spiral transverse reinforcements called MTSTR columns has not yet been investigated and compared with other types of columns under eccentric loads. In this regard, three types of concrete columns, concrete-filled steel tube column (CFST), traditional concrete column (TCC) and MTSTR column were simulated in this study

ABSTRACT The rocking response of anchored rigid bodies with irregular geometry is evaluated, incorporating the non-linearity of restrainers. A parametric analysis is performed, introducing the concept of Probability Reduction Spectra (PRS) to identify the influence of the main parameters into the rocking response as a function of the fundamental frequencies (excitation/body). The results allow identifying

ABSTRACT Elastic flexibility of a viscous damper sub-system can alter the phasing of damper and structural forces. This paper investigates how damper sub-system flexibility affects overall seismic response, using linear and nonlinear dampers. A suite of analyses with damped single degree-of-freedom systems show that a damper with significant flexibility can experience median peak displacements 40%

ABSTRACT For underground structures with large spans, such as buried pipelines, the seismic motions may vary not only at distinct horizontal locations due to the wave passage, incoherence and local site effects; but also at different vertical soil depths owing to the site amplification effect. This paper numerically investigates the influences of underground spatially correlated earthquake motions

ABSTRACT Spatial correlations of peak ground and pseudo spectral acceleration are estimated as a function of intersite separation distance and natural vibration periods. More than 2286 three-component records from 461 Iranian earthquakes are employed to evaluate the intra-event residual correlation based on multiple earthquakes, considering both local and regional ground motion prediction equations

ABSTRACT Based on the proposed material model, through the finite element method, the influences of the strain rate and the recycled coarse aggregate (RCA) replacement ratio on the structural behaviors and the damage evolution of the recycled aggregate concrete (RAC) structure are thoroughly investigated. The corresponding empirical formulas of the influence factors are proposed. It is revealed that

ABSTRACT This article reviews the current state of practice in seismic risk mitigation, focusing on policies in ten of the most earthquake-prone countries around the world. In particular, the review compares policies to retrofit existing buildings and mechanisms for financing seismic risk mitigation, within the context of seismic risk and design standards for each country. The goal of the review is

ABSTRACT A methodology based on probabilistic seismic risk analysis to estimate damping factors (Fmd) which modify the spectrum of elastic displacement with uniform annual exceedance rates (UAER), is proposed. Such factors take into account both a) energy dissipation of the hysteretic dissipaters and b) seismic hazard of the site. It is shown the importance of taking into account the type of soil for

ABSTRACT In this research, dynamic characteristics of 46 damaged or retrofitted buildings (22 RC and 24 steel buildings) induced by Sarpol-e Zahab earthquake are determined by ambient vibration tests. The obtained results are compared with the results of proposed empirical relations between codes and literature. Furthermore, empirical relations are proposed for calculation of fundamental periods of

ABSTRACT The uplift effects on the seismic demands of flexible SDOF structures rocking on a stiff surface were numerically investigated, under impulse excitations. The final results were represented in the form of spectra for the seismic demands including the foundation rotation angle, structural drift and base shear. Comparing the results indicated that as the normalized natural frequency surpassed

ABSTRACT This paper presents an application of the Conditional Mean Spectrum (CMS) methodology for sourcing accelerogram records for use in dynamic analyses of structures in intraplate regions of lower seismicity. The main challenges with deriving CMS for selecting and scaling accelerograms in regions of lower seismicity stem from the paucity of representative strong motion data and event recurrence

ABSTRACT The site fundamental period plays a key role in the characterization of site conditions to construct design spectrum models. For layered soil profiles on bedrock, it is generally believed that radiation damping caused by energy leaking into the bedrock does not change the fundamental period. This study finds that radiation damping can significantly affect the fundamental period. The effect

ABSTRACT This paper focuses on the ductility demand of self-centering structures with flag-shaped (FS) hysteretic behavior under near-fault (NF) pulse-like ground motions. To this end, the general features of spectral regions for the NF pulse-like ground motion are first described. The effects of structural and ground motion characteristics on the ductility demand spectra are further carried out. The

ABSTRACT This paper investigates the total life-cycle cost of designed structures with different increasing seismic response coefficient from the aspects of the structural and social life-cycle damage costs combined with environmental impacts. The environmental impacts are converted to the equivalent costs as much as possible, to be integrated with other social and economic factors. The proposed framework

ABSTRACT This study investigates the effects of near- and far-fault ground motion on the seismic behavior of historically inclined minarets. Inclined minarets built in Aksaray and Sivas, Turkey, are selected as numerical applications. The top of the Aksaray and Sivas minarets is 1.30 m and 1.23 out-of-plumb and the inclination values are 2.45° and 1.97°, respectively. Firstly, 3D finite element models

ABSTRACT A new external retrofitting sub-structure is proposed, namely, self-centering precast bolt-connected steel-plate reinforced concrete buckling-restrained-brace-frame (SC-PBSPC BRBF). Based on the 3D numerical model and stiffness-based design method, five retrofitting scenarios are performed on a deficient frame building to compare the upgrading effects. Probabilistic seismic performance assessments

ABSTRACT This work aims estimating seismic losses in residential-reinforced concrete buildings, highlighting the influence of infills and services. First, the mechanical-based “POST”-method is used to perform simplified (nonlinear static) structural analyses, in the “shear-type” building hypothesis. Then, drift-based fragility curves and repair cost analysis, specific for infills and services, are

ABSTRACT The seismic performance of a two-story building was investigated through a small-scaled quasi-static test. The test results show that the bolt-assembled PC panel building system can present reliable structural integrity, including transferring shear action and performing deformation ability. Based on the results, the failure mode and force-transfer mechanisms of the system were discussed and

ABSTRACT The displacement-based assessment procedure of Priestley and co-authors was formulated to provide either a pass-fail type of assessment or an indication of the likelihood of exceeding a selected limit state. To account for the effect of uncertainty in demand and capacity as part of the displacement-based assessment, it has also been shown that the SAC-FEMA approach can be adopted. In this

ABSTRACT A variety of yielding dampers have been proposed with different materials and configurations and constructed for various structures to improve their seismic performance. ADAS dampers are considered as energy dissipation tools to experience uniform yielding according to their specific geometry. However, the damper cannot perform ideally in large deformations due to an unexpected tensile axial

ABSTRACT This study presents a mathematical solution to evaluate the response characteristics of a tapered pile embedded in cross-anisotropic medium, under lateral harmonic force. The resistance of the cross-anisotropic viscoelastic half-space to a harmonic force acting in the lateral direction is obtained. The soil is demarcated into an interior weakened and an exterior linear region. The proposed

ABSTRACT Seismic performance of flexurally-dominated reinforced concrete (RC) walls largely depends on the ability of its confined end regions to withstand axial stress reversals. Observed compression failure modes in these end boundary regions during the Chile (2010) and New Zealand (2010–11) earthquakes led to extensive experimental research that involved testing isolated rectangular columns (or

ABSTRACT For the tridirectional time histories for seismic analysis, current codes and standards cannot guarantee isotropy in the horizontal directions, the code formula for statistical independence between components is not rigorous, and the bounds are arbitrary. In this paper, three conditions are defined for the horizontal inputs to be isotropic. Orthogonality is proposed to replace the statistical

ABSTRACT Accelerometers in smart devices have been used to successfully provide valuable information such as early warnings of earthquake activity and health monitoring of buildings. The next important step of using the acceleration measurements from smart devices is to assess building seismic damage, which is a more challenging application. A main challenge is related to the sliding motions of smart

ABSTRACT Glazing damage reported following recent New Zealand earthquakes, i.e. the 2011 (Mw 6.2) Christchurch and 2016 (Mw 7.8) Kaikōura earthquakes, exceeded what would be expected from glazing designed or tested to council’s compliance pathways, which indicates improvements are required to the existing pathways. Two series of proof-of-concept tests were conducted to induce simulated seismic actions

ABSTRACT The Korean peninsula is in a stable continental region with moderate seismicity. The first and second largest instrumented earthquakes occurred in the peninsula on September 12, 2016 and November 15, 2017, respectively, which inflicted major damage on structures in nearby populated cities. This study aims to propose a ground motion prediction equation (GMPE) for the peninsula using both ground

ABSTRACT This article develops ground-motion models (GMMs) by using a support vector regression (SVR) for western part of China. These SVR GMMs constitute mathematical equations that can predict the peak ground acceleration (PGA) and response spectral acceleration at different periods. Given the earthquake magnitude (M w), hypocentral distance (R hypo) and shear-wave velocity averaged over the top

ABSTRACT The paper discusses the performance of prefabricated reinforced concrete (RC) buildings, known as large-panel buildings (LPE), that were affected by the November 26, 2019 Durrës, Albania earthquake (M 6.4). This was a common typology for multi-family housing in urban areas of Albania and neighbouring countries, e.g. ex-Yugoslavia, Romania, and Bulgaria, in the period from 1960 to 1990. The

ABSTRACT The improvement of the seismic performance of existing buildings is majorly accomplished by adopting one or more retrofitting interventions. The selection of the latter is generally made considering conventional parameters, based on e.g. economic or structural considerations, without carrying out a comprehensive and integrated comparison of different retrofitting solutions. Instead, for an

ABSTRACT This study investigates the effects of seismic damages and retrofitting on dynamic characteristics of substandard reinforced concrete buildings. Two identical 3-story buildings were constructed, one of which was retrofitted through application of carbon fiber-reinforced polymer jacketing on its columns. Ambient vibration tests were conducted at undamaged states, and after formation of damages

ABSTRACT In this paper, the influence of brick masonry infill walls on the seismic performance of reinforced concrete (RC) frames is investigated. The presence and the location of a door opening are considered as test variables. Four RC frames were tested: a control specimen (RC bare frame), an infilled RC frame, an infilled RC frame with door opening at the loading end, and an infilled RC frame with

ABSTRACT The hybrid steel frame is a new laterally resistant steel frame composed of rigid and semi-rigid connections. The objective of this study is to select a hybrid frame with an appropriate seismic performance based on a multi-criteria decision-making approach. The seismic performance of different patterns and positions of semi-rigid connections within the selected frames is examined. Static,

ABSTRACT The poor out-of-plane behaviour of masonry infill-walls (MIW) in recent earthquakes, resulted in several casualties and economic losses. The main objective of this work is to present an experimental campaign comprised of four out-of-plane tests of full-scale MIW with the main goal to assess the possible effect of the previous damage, workmanship and test setup in the MIW out-of-plane behaviour

ABSTRACT This paper presents a simplified numerical modeling technique for nonlinear static and dynamic seismic analysis of Dhajji-Dewari structures. The technique comprised idealizing timber beam/column members as an elastic beam-element, diagonal and horizontal braces as an inelastic beam-element with fiber-section, and the connection capacity is simulated using lumped plasticity hinges for tension/rotational

ABSTRACT This paper describes techniques for detecting bearing malfunction directly from the seismic response of the bridge using wavelet transform time-varying identification. Instantaneous frequency of continuous wavelet and detail components of discrete wavelet transform are utilized as structural features, and they characterize isolation bearing condition via statistical clustering technique. Accuracy

ABSTRACT Three T-shaped concrete walls built with HRB 600 MPa reinforcement were tested under cyclic loading, and research parameters included axial load ratio and lateral loading direction. As part of the study, the method to obtain the yield strength and deformation was proposed. Test results show that compared to the specimen loaded along the web length direction, the wall loaded at 45° direction

ABSTRACT The effect of mainshock-aftershock (MS-AS) sequences on seismic performance of ordinary reinforced concrete (RC) moment frames (ORCFs) is studied by considering various levels of mainshock damage represented by maximum inter-story drift (MID) parameter. Incremental dynamic analysis (IDA) is performed to extract collapse capacity of structures under aftershock records after imposing the intended

ABSTRACT Base shear and sloshing response control in ground-supported circular cylindrical liquid storage tank is achieved by oblate spheroid base isolation (OSBI) system used along with floating surface diaphragm on the contained liquid. The new base isolation system, OSBI proposed herein is based on rolling-friction mechanism in ellipsoidal-shaped isolators in both the horizontal axes. The surface

ABSTRACT Soil–structure interaction (SSI) effects on the dynamic response of reinforced concrete (RC) wall-frame dual system have not adequately been investigated and are usually not considered in the engineering practice. In this study, the seismic behavior of the RC wall-frame dual system is studied in detail. The main goal of this research is to obtain the base shear contribution ratios of the dual

ABSTRACT Shake-table tests of a 3-story reinforced concrete building with cladding casted to be monolithic with frame elements, with seismic slits or cut reinforcing bars present in some cladding elements to ensure a desirable deformation mechanism, was performed at E-Defense to evaluate its post-disaster functionality. The building satisfied response objectives; behaving elastically with 0.33% drift

ABSTRACT A novel three-dimensional (3D) seismic isolator combining the quasi-zero stiffness (QZS) system in the vertical direction with the friction pendulum system in the horizontal direction is presented and applied to a moderately tall building model. The isolation system dynamic properties are first assessed in vertical and rotational directions separately using a simplified 3D model based on an

ABSTRACT This article proposes a rotation-restrained energy-dissipation device (RED) for the seismic control of a three-span curved isolated bridge. The configuration and working mechanism of RED are introduced in detail, and the finite element and simplified model are therefore derived. The seismic responses, parametric analysis and ground motion sensitivity analysis of the isolated bridge with and

ABSTRACT The geometry of skewed and curved bridges can cause complexity of their dynamic response and difficulty of analysis against earthquakes. In addition, when vibration occurs in the curved bridges, due to their specific geometry, the vertical, flexural, and torsional vibrations of the deck are coupled. The present study was carried out aiming to investigate the effect of non-uniform vertical

ABSTRACT Base shear and sloshing response control in ground-supported circular cylindrical liquid storage tank is achieved by oblate spheroid base isolation (OSBI) system used along with floating surface diaphragm on the contained liquid. The new base isolation system, OSBI proposed herein is based on rolling-friction mechanism in ellipsoidal-shaped isolators in both the horizontal axes. The surface

ABSTRACT Soil–structure interaction (SSI) effects on the dynamic response of reinforced concrete (RC) wall-frame dual system have not adequately been investigated and are usually not considered in the engineering practice. In this study, the seismic behavior of the RC wall-frame dual system is studied in detail. The main goal of this research is to obtain the base shear contribution ratios of the dual

ABSTRACT This article proposes a rotation-restrained energy-dissipation device (RED) for the seismic control of a three-span curved isolated bridge. The configuration and working mechanism of RED are introduced in detail, and the finite element and simplified model are therefore derived. The seismic responses, parametric analysis and ground motion sensitivity analysis of the isolated bridge with and

ABSTRACT A methodology is developed for generating floor response spectra (FRS) considering the effect of dynamic soil–structure interaction (SSI) based on the substructure technique and a recently-developed direct spectra-to-spectra method. Dynamic stiffness matrix of a three-dimensional structure with a rigid foundation subject to three translational and three rotational base excitations is derived

ABSTRACT In many researches and engineering projects, in order to control the uncertainty of ground motions, a large number of Time History Analyses (THAs) are used with a time-consuming process. To reduce the computation time, this study proposed four truncation methods that truncates the trailing records based on the principle of structural maximum displacement response equivalence. By investigating

ABSTRACT The dynamic response of freestanding structures is poorly predicted due to known sensitivity to geometry and input motion. To further elucidate the salient features of this dynamic response, the aim of this study is to investigate the response of complex freestanding systems under real-world conditions. Two statue-pedestal systems that overturned during the 2014 South Napa Earthquake are employed

ABSTRACT Pounding among internal structural parts of seismically isolated structures may happen because of high horizontal deformability of the isolation system. To study this poorly investigated issue, a reinforced concrete (r.c.) framed structure built in Sicily (Italy) is considered, with a hybrid isolation system combining elastomeric and sliding bearings. The building consists of four-storey,

ABSTRACT The use of elastomeric bearings for base isolation is well established through several studies. This paper is mainly focused on an innovative Fiber-Reinforced Bearing (FRB) developed using recycled rubber (RR-FRBs) and glass fabric reinforcement. These bearings tend to have better dissipation capacity, low weight and reduced cost in comparison with conventional Laminated Rubber Bearings (LRBs)

ABSTRACT Bidirectional quasi-static cyclic loading was applied to a subassembly of drywall partition walls integrated with cross-laminated timber rocking walls. Details aimed to reduce seismic damage to the partition walls were investigated, such as slip connections of partition walls to the diaphragm and gap detailing for the wall intersections. Telescoping detailing eliminated damage to the framing

ABSTRACT This study presents an overview of seismic hazards in Bhutan and the vulnerability of Bhutanese vernacular constructions derived from damage caused by two earthquakes that occurred in 2009 and 2011. Interpretations of damage and seismically vulnerable features of such constructions are provided from field observations. The taxonomy and vulnerability of all existing Bhutanese buildings are

ABSTRACT The close proximity of some populated cities all over the world to the active faults shows the necessity to investigate the consequences of the prominent characteristics of near-fault pulse-like ground motions (i.e., the forward directivity and fling-step) on the seismic performance of the code-compliant multi-story buildings. This paper attempts to quantify the effects of pulse-like near-fault

ABSTRACT This paper summarizes a sophisticated field investigation of the seismic damage to a continuous rigid frame bridge. Cracking and deformation of main girder, failure of bearings, and damage of piers were examined. The whiplash effect of the long side span of main bridge caused the prominent damage of bearings and restrainers on the transition piers. A numerical model was developed for supplementary

ABSTRACT The precise description of reinforced concrete shear wall (RCSW) systems under severe dynamic loading remains a difficult research question owing to the intrinsically multi-scale underlying mechanisms, ranging from building’s irregularity to individual core walls, and even to the millimeter length-scales nonlinear shear over cracks and progressive steel bar buckling. This study adopted a parallel

ABSTRACT This study presents a novel hybrid self-centering system aiming to overcome critical shortcomings identified in the existing self-centering solution. Two types of hybrid brace incorporating shape memory alloy elements and integrated viscoelastic dampers are first introduced, followed by a system-level analysis on a series of prototype buildings. The results show that using viscoelastic material

ABSTRACT In recent earthquakes in Japan, it was difficult for some reinforced concrete buildings to maintain their functionality after earthquakes due to damage to nonstructural RC walls. Currently, society expects quick recovery, if not uninterrupted functionality, of buildings after earthquakes. In this paper, four hybrid rocking wall specimens, along with rocking wall and RC wall were tested to