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This paper proposes an energy-based method to determine the structural responses of steel beam-concrete slab composite substructures under side column removal scenarios. A tri-linear resistance-displacement curve is proposed. Three factors contributing to the internal energy dissipation are accounted for, including the extension of reinforcing bars and steel beams, the additional bending moment induced from membrane forces in the slab and tensile forces in beams, and sectional bending moment along yield lines of the slab. Parametric studies are conducted based on validated finite element models to investigate the effect of slab planar aspect ratio, slab thickness, slab reinforcement ratio and beam section height on the behavior of composite beam-slab substructures subjected to side column loss. The numerical results show that these four parameters have limited effects on the yield displacement of the substructure. The accuracy and effectiveness of the proposed method are verified against numerical results with errors less than 15%. It is found that the first two factors considerably contributed to the collapse resistance of the substructures at large deflections, by accounting for more than 70% of the total energy dissipation capacity. The contribution from the slab at the collapse limit state is mainly influenced by its reinforcement ratio. [ABSTRACT FROM AUTHOR]

Violent vibrations have been reported in the vertical hangers of long-span suspension bridges, especially for those located in the vicinity of the towers. In the present study, an experimental investigation is performed to characterize the wake-flow-induced vibrations of vertical hangers behind the tower of a suspension bridge. The tower column and vertical cable models are determined by using a long-span suspension bridge with a geometrical scale ratio of 1:10. Regular vortex shedding from the tower column model is detected in the near wake with a Strouhal number ( St ) of 0.20, and the turbulence intensity of the wake flow behind the tower column model is found to be quite high. Arranged at different stations behind the tower column model, the vertical cables experience violent vibrations. The vibration frequencies of the vertical cables are synchronized with the vortex shedding from the upstream tower model within a certain velocity range, during which severe cable vibrations take place. When the incoming wind speed becomes high, the cable vibrations exhibit multimode characteristics. It is also found that the vertical cables arranged at the rear are subject to the combined interferences of the tower column model and the front cables. As a result, the vibration responses of the rear cables are more violent than those of the front cables. [ABSTRACT FROM AUTHOR]

The probabilistic estimation of the magnitude of historical earthquakes requires the analysis of actual building structures affected by those earthquakes. The analysis complicates because most of these buildings no longer exist or were greatly modified, present a great variety of features and the number of analysis for probabilistic assessment is high. As it is not practical to analyze all structures, an alternative is to use structural archetypes representing the affected buildings. This paper presents an approach to develop a quantitative framework for the generation of historical archetypes. The method is illustrated via the definition of a specific archetype for the study and assessment of the effects of the 1763 Komárom earthquake. The historical survey of Tata, Hungary, is assumed as representative of the region and one historical building is utilized to illustrate the archetypes evaluation process. [ABSTRACT FROM AUTHOR]

Rapid and reliable estimation of earthquake magnitude has a significant effect on proper performance of earthquake early warning system. In recent years, three methods including predominant period (τpmax), characteristic period τc, and log-average period (τlog) have been introduced for estimation of earthquake size based on frequency contents within the first few seconds of P-waves. In the current study, new power-spectrum parameter, τps in the modified form of τlog approach, is introduced by using waveforms of 70 earthquakes occurred in Japan with magnitudes ranging between MJMA 3.0 and 8.0. Results demonstrate that τps values have no significant weighted dependency on amplitude and frequency contents, and are better correlated with the reported magnitudes compared to other frequency-based proxies. It is also shown that τps and τpmax magnitude-scaling relationships provide more precise and robust event size estimation than τc and τlog approaches, especially for small events. Thus, by using τps parameter it has been expected that performance of earthquake early warning systems (EEWS) will improve by reducing the rate of false alarms. [ABSTRACT FROM AUTHOR]

Most of the existing studies on reticulated shells with a semi-rigid joint system have been focused on the mechanical properties under static loads. Taking material and geometric nonlinearities into account, the finite element analysis (FEA) model of a single-layer reticulated shell with semi-rigid joints was established using the software ABAQUS and then validated through comparison with the experimental result. Based on the bending stiffness of a bolt-column (BC) joint obtained through experiments, the dynamic behaviour and a seismic design method for single-layer reticulated shells with semi-rigid joints were investigated in this paper. First, analysis of the free vibration frequency of the single-layer latticed domes with semi-rigid bolt-column (BC) joints was conducted based on several different parameters, including joint stiffness, ratio of rise to span, initial geometric imperfection. Second, the seismic internal force coefficient of the members of the semi-rigidly jointed spherical single-layer reticulated shells of different parameters was studied in detail. Finally, the seismic internal force coefficients for spherical single-layer reticulated shells with semi-rigid joints under a common earthquake were derived. [ABSTRACT FROM AUTHOR]

The purpose of the present paper is to develop a simple methodology for seismic life cycle cost (LCC) estimation for a steel jacket offshore platform structure. This methodology accounts for accuracy of LCC modelling as well as simplicity of application. Accuracy is maintained through incorporating the effect of aleatory and epistemic uncertainties in the LCC estimation framework. Simplicity is achieved by using equivalent single-degree-of-freedom (ESDOF) system instead of the full structure and by eliminating full incremental dynamic analysis and fragility analysis. Instead, an approximate fragility curve and a localised incremental dynamic analysis curve are used along with a probabilistic simple closed-form solution for loss estimation. In the design of model structures, different bracing systems are used for the seismic design of the offshore platform, such as conventional and buckling-restrained braces. The proposed LCC methodology is validated through comparison with the results from a more rigorous method. It is found that even though the proposed methodology results in a slightly different solution compared to the reference method, the method can be used as an efficient tool for preliminary LCC evaluation of structures. [ABSTRACT FROM AUTHOR]

Tsunamis are rare destructive phenomena caused by the sudden displacement of a large amount of water in the ocean and can result in enormous losses to coastal communities. The resilience of coastal communities to tsunamis can be improved through the use of risk-informed decision making tools. Performance-Based Engineering (PBE) approaches have been developed for different natural hazards including earthquake, fire, hurricane, and wind to perform probabilistic risk assessment for structures. In this study, a probabilistic Performance-Based Tsunami Engineering (PBTE) framework based on the total probability theorem is proposed for the risk assessment of structures subject to tsunamis. The proposed framework can be disaggregated into the different basic analysis phases of hazard analysis, foundation and structure characterization, interaction analysis, structural analysis, damage analysis, and loss analysis. An application example consisting of the risk assessment of a three-story steel moment frame structure was performed using the proposed framework. The probability of exceedance of the total replacement cost including structural, nonstructural, and content losses were computed. [ABSTRACT FROM AUTHOR]

Two full-scale, two-story, low-ductility steel concentrically braced frame (CBF) systems were tested to evaluate failure mechanisms, postelastic frame behavior, reserve capacity, and overall collapse performance. These frames were designed for a moderate seismic region, where reserve capacity is emerging as a parameter that can be employed instead of primary system ductility to economically prevent seismic collapse. One test unit used a split-x bracing configuration and satisfied seismic detailing and proportioning requirements in the AISC Seismic Provisions for an ordinary concentrically braced frame (OCBF) with R ¼ 3.25. The other test unit used a chevron CBF configuration with R ¼ 3 and included no seismic detailing. Each test unit was subjected to a quasistatic cyclic loading protocol and was cycled to total frame drifts in excess of 3.0%. The split-x OCBF exhibited ductile brace buckling behavior up to 1.5% total frame drift, but possessed little reserve capacity after two weld fractures. The R ¼ 3 chevron CBF exhibited brittle brace buckling and subsequently developed several distinct reserve capacity mechanisms. These tests demonstrate overall hysteretic behaviors that are highly dependent on two underlying design parameters: system type and system configuration. OCBF brace local slenderness and connection capacity design requirements are effective for providing ductile brace-buckling behavior. The split-x configuration appears more vulnerable to developing multistory mechanisms that possess limited reserve capacity, but this can be improved with strategically placed, enhanced beam-column connections. The chevron configuration is more prone to single-story mechanisms that possess significant reserve capacity developed through beam and column flexure. [ABSTRACT FROM AUTHOR]

The level of structural damage and the associated economic impact caused by recent earthquakes worldwide have spurred an increased interest in high-performance seismic-resisting systems that can sustain severe earthquakes with minimal damage. A particularly efficient high-performance wall system consists of precast concrete panels vertically posttensioned to the foundation with unbonded posttensioning steel. The system relies on the vertical unbonded posttensioning steel for flexural strength and recentering, while mild bonded steel bars provide energy dissipation and additional flexural strength. Experimental results are presented from a dynamic test on a full-scale 4-story precast concrete building that utilized unbonded posttensioned (UPT) walls in one direction and bonded posttensioned concrete frames in the orthogonal direction. The excellent performance of the test building in the wall direction of response, exhibiting minimal damage and no residual deformations, confirms that UPT walls are a viable alternative to conventional RC structural walls. [ABSTRACT FROM AUTHOR]

The three most common nonlinear displacement-based methods were applied in the seismic design of two bridges in western Tennessee, and their results in terms ofmaximum seismic displacement demand and displacement ductility were compared. In addition, two different support-modeling configurations were evaluated. The results indicate that use of the simplified LRFD procedure results in a displacement demand higher than that of the other procedures. The support configuration with simplified seat-type abutments with rigid bent foundations provides results not significantly different than those achieved from the more detailed configuration with stub-wall abutment with flexible bent foundations, but it required fewermodeling efforts. [ABSTRACT FROM AUTHOR]

Different from previous researches which mostly focused on linear response control of seismically excited high-rise buildings, this study aims to control nonlinear seismic response of high-rise buildings. To this end, a semi-active control strategy, in which H∞ control algorithm is used and magneto-rheological dampers are employed for an actuator, is presented to suppress the nonlinear vibration. In this strategy, a modified Kalman-Bucy observer which is suitable for the proposed semi-active strategy is developed to obtain the state vector from the measured semi-active control force and acceleration feedback, taking into account of the effects of nonlinearity, disturbance and uncertainty of controlled system parameters by the observed nonlinear accelerations. Then, the proposed semi-active H∞ control strategy is applied to the ASCE 20-story benchmark building when subjected to earthquake excitation and compared with the other control approaches by some control criteria. It is indicated that the proposed semi-active H∞ control strategy provides much better control performances by comparison with the semi-active MPC and Clipped-LQG control approaches, and can reduce nonlinear seismic response and minimize the damage in the buildings. Besides, it enhances the reliability of the control performance when compared with the active control strategy. Thus, the proposed semi-active H∞ control strategy is suitable for suppressing the nonlinear vibration of high-rise buildings. [ABSTRACT FROM AUTHOR]

Seismic vulnerability analysis of historical masonry buildings, addressed to earthquake emergency management and protection strategy planning, requires large-scale vulnerability and damage assessment. In this sense, two seismic vulnerability index methods and damage estimation have been adapted and applied to a pilot-scale urban area located in Annaba city (Algeria). The first method is based on the EMS-98 building typologies, and the second is based on the Italian GNDT approach. To accomplish this task, the authors employed an existing data survey, which, however, was not originally developed for seismic purposes. It was used herein to provide input to the vulnerability methods. The main goal of this research is not only to assess the seismic vulnerability and expected damage within Annaba, but also to adapt the two mentioned approaches to the existing data survey, aiming to use such nonspecific building database and to study the possibility of its application for seismic risk estimation in similar regions. The results obtained from the application of these two methods were integrated and compared using a geographic information system, proving that the vulnerability of the buildings surveyed in Annaba is significant, and therefore risk mitigation efforts and public awareness are required. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop modeling strategies to accurately model column behavior under seismic loading, including residual displacement. To this end, seven shaking table tests are considered to evaluate the accuracy of existing modeling approaches in capturing residual displacement, maximum displacement and base shear. It is found that, although the recommended modeling strategies can estimate maximum displacement and maximum base shear with reliable accuracy, but the discrepancy of their results corresponding to residual displacement are unacceptable. Following this, a modified concrete constitute model representing damage accumulation from cyclic loading is implemented for the fiber-element analysis. Analyses using modified concrete constitute model leads to decrease the error of modeling strategies in capturing residual displacement. [ABSTRACT FROM AUTHOR]

The restoring (or re-centring) capability is an important feature of any isolation system and a fundamental requirement of current standards and guideline specifications for the design of seismically isolated structures. In this paper, the restoring capability of spherical sliding isolation systems, often referred to as friction pendulum systems (FPSs), is investigated through an extensive parametric study involving thousands of non-linear response history analyses of SDOF systems. The dynamic behavior of the isolation system is described with the visco-plastic model of Constantinou et al. (J Struct Eng 116(2):455-474, ), considering the variability of the friction coefficient with sliding velocity and contact pressure. Numerical analyses have been carried out using a set of approximately three hundred natural seismic ground motions recorded during different earthquakes and differing in seismic intensity, frequency content characteristics, magnitude, epicentral distance and soil characteristics. Regression analysis has been performed to derive the dependency of the residual displacement from the parameters governing the dynamic response of FPS. The influence of near-fault earthquakes and the accumulation of residual displacements due to real sequences of seismic ground motions have been also investigated. Finally, the restoring compliance criteria proposed in this study are compared to the lateral restoring force requirements of current seismic codes. Based on the results of this study, useful recommendations for a (more) rational design of FPSs are outlined. [ABSTRACT FROM AUTHOR]

An innovative displacement-based seismic design procedure for regular planar framed structures considering sidesway collapse prevention is presented. The method proposed, based on the characterization of a multiple degree of freedom system by means of a single degree of freedom system, allows the design of structures with a P-Delta induced negative stiffness to satisfy an interstorey drift threshold and/or prevent dynamic instability. The design procedure relies on the use of elastic analysis of simplified models and collapse or constant ductility spectra, hence, non-linear dynamic analyses are not required. To illustrate the potential of the method proposed, example applications and validation of the results obtained via incremental dynamic analysis are shown. [ABSTRACT FROM AUTHOR]

Integral abutment bridges have certain advantages over conventional seat-type abutment bridges due to increased redundancy, higher damping, smaller displacements, and, thus, the elimination of unseating potential. However, there is a lack of information on their seismic modeling, system response, and seismic design. This paper presents the recommended guidelines for the seismic design of steel bridges with integral abutments. These guidelines are based on extensive analytical investigations as well as available experimental research. Contrary to the common assumption in analysis and design, nonlinear finite element analyses showed that the typical girder-to-abutment connection is not rigid and can influence the overall seismic response of the bridge. A procedure for calculating the minimum required embedment length of the girder into abutment stem to achieve a rigid connection is proposed. A procedure to evaluate the steel pile ultimate lateral displacement capacity is also proposed. The use of the system-level damping due to yielding and inelastic response of the various components including the soil behind the abutments and around the piles is discussed. [ABSTRACT FROM AUTHOR]

A computational framework is proposed as an automated design cycle for the optimal seismic design of steel frames with self-centering connections. This paper demonstrates the approach by considering steel frames retrofitted with posttensioned energy dissipating (PTED) connections. A multiphase genetic algorithm is applied for discrete optimization to determine robust steel moment-resisting frame (MRF) designs incorporating PTED connections. Nonlinear dynamic time history finite-element analyses are employed to evaluate potential designs. For the case studies in this paper, results indicate that the performance of the MRF with optimal PTED connections exceeds that of MRFs with conventional moment-resisting connections for a specified seismic environment. This suggests that the PTED connections are a promising alternative to conventional welded moment-resisting connections in seismic regions. Furthermore, the developed computational framework is shown to provide an attractive approach for the design of MRFs with PTED connections and may be employed for the optimal design of other self-centering systems. [ABSTRACT FROM AUTHOR]

Three RC frame structure models were designed with various moment magnifying coefficients of columns and analyzed based on randomly incremental dynamic analysis in consideration of the parameter randomness of material, loads and the ground motion, using seismic peak acceleration as the vibration intensity indicators and the maximum vertex displacement angle as the reaction parameters of the structures to obtain the IDA curves of the structures, on the basis of the IDA, the seismic demand probability model of each structure was established, and four seismic performance levels were defined. Then the random pushover analysis for each structure was carried out to determine the various performance level limit value. Finally, seismic fragility analysis was carried out for each structure to obtain fragility curves. The results show that the moment magnifying coefficient value has a certain impact on the fragility of the structure. The greater its value is, the smaller the collapse probability of the structure under a specific earthquake motion is. Within a certain range (0. 2g ⩽ apg ⩽ 1. Og) , the larger the plastic degree of the structure is, the more obviously the seismic performance of the structure with a larger moment magnifying coefficient value is improved, the paper proposes that it may be appropriate to increase the moment magnifying coefficient value in the subsequent code revision. [ABSTRACT FROM AUTHOR]

The seismic protection of buildings by seismic isolation is continuously improving since many years. Many new materials and different shapes are contributing to the development of recent high performance devices. As seismic isolators installed between a structure and its foundation to protect it from damage due to earthquake shaking, double sliding bearings use the characteristics of a pendulum to lengthen the natural period of the isolated structure so as to avoid the strongest earthquake forces. They can protect structures and their contents during strong magnitude earthquakes, and architectural innovations are encouraged by the enhanced structural response achieved through seismic isolation. [ABSTRACT FROM AUTHOR]

The Retrofit Yield Spectrum (RYS) is a new spectrum-based device that relates seismic demand of a retrofitted structure with the fundamental design parameters of the retrofit. This is obtained from superposition of Yield Point Spectra with design charts that summarize in pertinent spectrum-compatible coordinates the attributes of a number of alternative retrofit scenarios. Therefore, once the requirements for upgrading a given structure have been determined, the RYS enable direct insight of the sensitivity of the seismic response of the upgraded structure to the preliminary design decisions made while establishing the retrofit plan. By virtue of their spectrum-based origin, RYS are derived with reference to a single mode of structural vibration; a primary objective is to control the contribution of this mode in the retrofit design so as to produce a desirable distribution of damage at the ultimate limit state by removing soft storey formations and engaging the maximum number of structural members in deformation, in response to the input motion. Calculations are performed with reference to the yield-point, where secant stiffness is proportional to the flexural strength of reinforced concrete members. Derivation and use of the Retrofit Yield Spectra (RYS) refers to the seismic demand expressed either in terms of spectral acceleration, spectral displacement or interstory drift, at yield of the first storey. A reinforced concrete building that has been tested in full scale to a sequence of simulated earthquake excitations is used in the paper as a demonstration case study to examine the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures, designed according to proper capacity design guidelines, can deform inelastically without loss of strength. Therefore, such structures need not be designed for full elastic seismic demand, but could be designed for a reduced demand. In codified design procedures this reduced demand is obtained by dividing the full elastic seismic demand by a code-defined behaviour factor. There is, however, no consensus in the international community regarding the appropriate value to be assigned to the behaviour factor. The purpose of this study is to assess the value of the behaviour factor currently prescribed by SANS 10160-4 (2011) for the design of reinforced concrete structural walls. This is done by comparing displacement demand to displacement capacity for a series of structural walls. The first step in seismic forcebased design is the estimation of the fundamental period of the structure. The influence of this first crucial step is investigated in this study by considering two period calculation methods. It was found that, regardless of the period calculation method, the current behaviour factor value prescribed in SANS 10160-4 (2011) is adequate to ensure that inter-storey drift of structural walls would not exceed code-defined drift limits. [ABSTRACT FROM AUTHOR]

To explain the failure mechanism of a retaining wall in an earthquake and put forward effective aseismic measures based on energy theory, and taken from the upper bound theorem as a measure, the safety of anchor system is defined, and then the mechanism of input and dissipation of seismic energy is studied. Furthermore, by analyzing the wave characteristics of a destructive earthquake, an aseismic design of a retaining wall is proposed according to the flexible retaining theory. At last, an example is given and the result shows that the seismic behavior of a common rigid retaining wall is poor and the structure fails quickly under large seismic force with specific direction. On the contrary, the new system with an EPS damping layer can dissipate seismic energy well. [ABSTRACT FROM AUTHOR]

Existence of hollow sections in precast hollow core wall makes it sceptical to resist earthquake loading. However, this wall can resist earthquake loading if it is designed as a hybrid wall system. It is equipped with unbonded tendons and bonded "fuse-bars" to dissipate energy. It rocks steel-on-steel without inducing any structural damages. In-plane lateral cyclic loading is applied on the wall. Experimental results show that the wall is able to resist earthquake loading without any structural damage. Direct displacement based approach is used to validate the experimental results. There are good correlations between them with very a small percentage of discrepancies. [ABSTRACT FROM AUTHOR]

Concrete structures are often subjected to dynamic loads, such as seismic, blast or impact loads. Under such loads, distinct changes may occur in the dynamic and damage behaviour of concrete. This paper presents the results of dynamic tensile tests of plain concrete specimens with axial strain rates ranging from 10/s to 10/s that were carried out on a servo-testing machine. Observed stages of damage evolution are divided into three phases: undeveloped, steadily developed and unsteadily developed. This study found that the stress threshold ratio of ultimate strength increases with strain rate, and that the initial tangent elastic modulus and Poisson's ratio are independent of the strain rate for the test specimens. Moreover, the tensile strength and critical strain of concrete increased approximately linearly with the logarithm of the strain rate, and an experimental relationship between strain rates and tensile strength, critical strain was established. Furthermore, dynamic tensile damage tests of concrete were carried out with axial strain rates ranging from 10/s to 10/s. The effects of loading histories on dynamic tensile strengths, dynamic stress-strain curves, and dynamic damage behaviour of concrete were studied. Results indicate that both dynamic tensile strengths and damage thresholds of concrete decreased while the given rated loading was applied compared with those samples that were not subjected to the load history. However, damage of concrete at the same stress ratio and strain ratio increased with the increasing load history. [ABSTRACT FROM AUTHOR]

Significant research efforts have been devoted in recent years to the development of displacement-based seismic assessment and design methodology, recognising the shortcomings of traditional, code-specified force-based procedures. Recent advances in direct displacement-based seismic design of columns rely on the estimates of yield curvature for determining seismic design forces to satisfy the specified seismic performance levels. This paper presents simple expressions for estimating the effective yield curvature for normal- and high-strength circular reinforced concrete columns based on moment-curvature analyses of a large number of column sections. Such expressions can be programmed into spreadsheet format and can be used for the direct displacement-based design of circular reinforced concrete columns. Influences of different parameters on the effective yield curvature have been quantified. Effective yield curvature is presented in terms of the gross diameter of the section and the yield strain of longitudinal reinforcement together with three modification factors that take into account the effects of the strength of concrete, axial load ratio and the amount of longitudinal reinforcement. An example illustrating the preliminary design of bridge columns based on the developed expressions is presented. [ABSTRACT FROM AUTHOR]

Plastic hinge length and ultimate curvature are the crucial parameters that enable inelastic deformability (deflection and rotation) of reinforced concrete columns to be evaluated. Prediction of deformability beyond the elastic range is important in the performance-based design of earthquake-resistant structures. Although large numbers of tests have been conducted in the past by numerous researchers on reinforced concrete columns subjected to simultaneous axial load and large inelastic displacement, available design tools that enable rapid evaluation of deformability of reinforced concrete columns are still limited. The situation is even worse for high-strength reinforced concrete columns. The objective of this paper is to investigate plastic hinge length and ultimate curvature for deformability evaluation of high-strength reinforced concrete columns. In connection with this, two equations are proposed in this paper for estimating the plastic hinge length and ultimate curvature of high-strength reinforced concrete columns leading to their deformability evaluation. The proposed equations are used to evaluate the theoretical deflection of other researchers' column test specimens, and it is proven that these theoretical deflections mostly underestimate slightly their respective measured deflections. Therefore, the proposed equations can be used for conservative estimation of high-strength reinforced concrete column deformability at an early design stage without performing the tedious load-deflection analysis. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a methodology for developing earthquake‐resilient structures (ERSs). This is achieved by following principles of full cycle performance control and embracing a holistic approach to design led analysis (DLA) of ERS. Collapse prevention (CP) and postearthquake realignment and repairs (PERRs) are the basic traits of ERS. Despite the availability of several systems involving combinations of gap opening link beams (GOLBs), rigid rocking cores, buckling‐restrained braces, replaceable energy dissipating moment connections, and so forth, neither CP nor PERR are addressed in any code of practice. Although most of these devices have passed several tests of experiments and time–history analysis they have rarely been examined as integral parts of actual buildings. Real buildings cannot be ideally recentered unless specifically designed and detailed for CP and PERR. Almost all simple beam–column joints, especially standard hinged supports absorb small but sufficient amounts of residual strains that hinder PERR. The proposed methodology is introduced by way of developing an earthquake‐resilient rocking core‐moment frame, as the lateral resisting component of a gravity resisting structure that has been detailed not to develop residual effects while sustaining large lateral deformations. [ABSTRACT FROM AUTHOR]

Seismic Design of Buildings to Eurocode 8, 2nd edition [ABSTRACT FROM AUTHOR]