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Seismic losses due to earthquakes have been shown to have significant economic, social and environmental consequences. Over recent years, research to predict potential economic and social impact due to seismic risk has been increasing. Recognizing that the traditional philosophy of life safety design can lead to extensive damage and demolition which has a large environmental cost, incorporating environmental impacts associated with the expected seismic damage over a building's life is a key step as the building industry moves towards both sustainable and seismically resilient design. This paper introduces a framework that uses environmental indicators quantifying losses from seismic response that can then be used to advocate for a change in seismic performance objectives. First, existing literature and previously developed approaches for quantifying potential environmental impact due to seismic damage are summarized. Next, performance based earthquake engineering concepts are used to demonstrate a probabilistic approach to quantify potential environmental impacts using a range of environmental and resource use indicators over the life span of a case study building. In addition, a case study is presented to compare different environmental indicators between a Code Minimum building and the same building redesigned for a higher seismic performance. The majority of the composition of the environmental indicator values are from the inclusion of the non-repairable scenario, and from the repair activities, the majority of the impacts are from damage to drift sensitive components including curtains walls, partitions and elevators. For the Code Minimum building the non-repairable scenario contributes to between 8 to 11% the total seismic cost. For the Stronger Stiffer building, the non-repairable scenario contributes around 3% of the initial impact. Neglecting non-repairable scenarios does significantly reduce the potential environmental impacts when analyzing buildings designed for current code minimum structural standards. [ABSTRACT FROM AUTHOR]

On the 26th of November 2019, an earthquake of moment magnitude 6.4 struck the northwest region of Albania as the result of thrust faulting near the convergent boundary of the Africa and Eurasia plates causing widespread damage to buildings in the city of Durrës and the surrounding areas. Based on the official data from the national authorities, the earthquake caused 51 casualties and 985 million-euro losses, corresponding to 7.5% of the 2018 gross domestic product. This paper summarises field observations made by the Earthquake Engineering Field Investigation Team (EEFIT) after the event. The paper presents an overview of the seismological aspects of the earthquake together with a brief overview of the damage, official loss statistics and the estimated macro- and socio-economic consequences of the event. In addition, it provides a summary of the observed damage to both recent and historical buildings as well as the description of several case studies to illustrate the characteristic damage patterns observed in the main structural typologies of the Albanian building stock. These observations try to identify possible links between the observed damage patterns and the deficiencies in construction practice and use of inappropriate retrofit techniques for historical assets. As many severe damages were observed on modern buildings, this also allows the identification of some gaps and possible areas of development of the current seismic design code. In the end, the lessons learned from the field survey are resumed. [ABSTRACT FROM AUTHOR]

In May 2012, two strong earthquakes hit the northern Italy revealing the significant seismic vulnerability of precast reinforced concrete structures and causing severe damage and many collapses, and high economic losses. After the lesson learnt from these events, more reliable seismic design criteria have been established for the design of new structures and different approaches have been proposed for the seismic assessment of the existing structures. In this context, the paper presents the results of a first application of the PRESSAFE-disp method, recently proposed by the authors, allowing to define the fragility curves of precast RC buildings at various limit states, including collapse. A stock of 91 precast buildings in the industrial area of San Felice sul Panaro (Modena) was selected as a benchmark case study to verify the reliability of the method in assessing seismic damage scenarios. In particular, with reference to the 2012 seismic ground-motion, two large-scale stochastic models are outlined to predict the number of the buildings collapsed in the area. The first one is based on a Monte Carlo simulation which incorporates the evaluation of the uncertainties, while the second one is a direct simplified calculation. Comparative considerations on the outcomes of the two methods for different seismic intensities are discussed, including the directionality effect of the ground-motion. To test the soundness of the simulations, the results of the two methods are compared with the real data collected through in-situ surveys. The procedures proposed here result, on average, in good agreement with the observed damage scenario. It is worth noting that, due to the inherent simplicity of the methods, they could be implemented to perform scenario-based seismic loss assessments to estimate the financial consequences of an earthquake affecting one or more industrial areas, and to drive the decision-making process for the seismic retrofit of existing precast RC buildings. [ABSTRACT FROM AUTHOR]

The study of the seismic response of long bridges under non-uniform seismic excitation date back to the early 80 s. So far, many methods have been developed to estimate the bridge responses under such excitation. Eurocode-8 is considered the first seismic design code that provided a simplified method for linear seismic analysis of long bridges under non-uniform seismic excitation. In this method, earthquake ground motion at each bridge support is decomposed into uniform and relative excitations. Any desired elastic response quantity of bridge for each input is obtained and results are combined using the SRSS combination rule. In this paper, it is shown that the SRSS method leads to very conservative and unrealistic responses. An alternative combination rule is then recommended for response estimation, and random vibration analysis is used to calculate the correlation coefficient between the two mentioned responses. Efficiency evaluation of the proposed method is investigated by Monte Carlo simulation results of nine long bridges with different geometrical and dynamic characteristics. Two simplified mathematical bridge models for longitudinal and transverse directions are developed. Then, a simple mathematical formula for the correlation coefficient is extracted, and its accuracy and performance are evaluated. Finally, it is concluded that the proposed formula is relatively accurate and appears in acceptable results. [ABSTRACT FROM AUTHOR]

In May 2012, a series of medium–high intensity earthquakes struck a highly industrialized area of central-northern Italy and in particular the Emilia-Romagna region. As a consequence, there were 28 casualties, numerous injuries, and vast damage to thousands of civil structures, infrastructures and industrial facilities. After that, the regional political authority, Regione Emilia-Romagna, spent billions of euro of state funding on reconstruction; as of 2018, almost EUR 1.9 billion was granted to business sector. In order to be able to fairly distribute financial aid to damaged productive facilities, a vast information system was created and data were stored in a database called SFINGE. Collected information regards losses, induced costs, reimbursements paid by the insurance companies, and money finally granted by the state. In this paper, we present the results of a study we conducted on the database; the requests for public funding were accessed and examined within a special scientific agreement between Regione Emilia-Romagna and RWTH Aachen University. Study results will be useful in predicting costs, economic losses and insurance refunds for business activities damaged by seismic events. Public authorities can learn too, as the paper presents a way of accounting consequences and granting public money that proved to work effectively. Finally, reported data can be included within the existing theoretical framework of Performance Based Earthquake Engineering, significantly contributing to the definition of seismic performance assessment tools. [ABSTRACT FROM AUTHOR]

The influence of distanced uniform strip load on the design of cantilever sheet pile walls under static as well as seismic condition is sudied in this paper. A simplified theoretical solution based on limit equilibrium approach is proposed to design the cantilever sheet pile walls having a distanced strip load in cohesionless soil. By considering the rigid rotation about pivot point and the displacement pattern, the active and passive earth pressure are assumed fully mobilise. To completely define the earth pressure distribution, horizontal force and moment equilibrium are considered to calculate the embedded depth. The influence of distanced uniform strip load has been observed by emplying Coulomb earth pressure theory. Expressions are given to calculate bending moment and shear force at any depth of the cantilever sheet pile walls. Some aspects to design the cantilever sheet pile walls with distanced strip load are also highlighted in terms of maximum bending moment, embedded depth and depth of pivot point from dredge level. Design charts in non-dimensional form are also given as a ready reference. [ABSTRACT FROM AUTHOR]

An investigation on seismic response characteristics and modal parameters of a cable-stayed bridge with movable bearings using vibration records obtained from a seismic monitoring system is presented in this paper. The object of this study is the Tokachi cable-stayed bridge, a single plane prestressed cable-stayed bridge that is equipped with moveable spherical frictional plate (SFP). The bridge seismic responses subjected to various levels of earthquake including the 2003 Tokachi Great earthquake were obtained from a permanent seismic monitoring system. The bridge dynamic characteristics that include frequency and damping were estimated by both the time-invariant and time-variant recursive subspace identification methods. The identification results reveal that damping ratios of the low order modes estimated during the largest earthquake can reach more than 10% of the critical damping, which is higher than what usually assumed in the seismic design code. Supplementary damping caused by friction force at the movable SFP bearings was identified as the main source of the large damping, and it was quantified by a modal-based inverse analysis using the sparse regularization method. Results of the analyses confirm the influence of moveable SFP bearings performance with its Coulomb-friction type stick–slip behavior on the dynamic characteristics of the bridge. The bearings remain stuck at smaller excitation causing higher stiffness of the structure and slip during a larger excitation resulting in stiffness reduction. The sliding process induces friction force between contacting surfaces of the SFP bearings which results in the increase of damping as the excitation level increases. The damping, however, does not increase continuously, but becomes steadier after a certain level of excitation. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive geological and geotechnical study of the whole area affected by liquefaction following the 2012 Emilia earthquakes, including all the available information from the field reconnaissance surveys, in situ tests, and laboratory analyses. The compilation was performed at 120 liquefied sites to verify and validate the reliability of liquefaction charts in alluvial sediments, and to assess liquefaction induced by the 2012 seismic sequence in the Emilia plain. The results reveal a wide range of grain sizes (from clean sands to sandy silts) and compositional characteristics (quartz-rich to litharenitic) in the 2012 ejecta, and show a strong relationship between the liquefaction and stratigraphic architecture of the subsurface. The availability of in situ tests at the liquefied sites makes it possible to verify and validate the reliability of the liquefaction charts in alluvial sediments with respect to the real observations. For the analyzed Emilia case studies, the use of non-liquefiable crust provides better estimations of the liquefaction manifestations when coupled with the thickness of the liquefiable layer rather than with the liquefaction potential index. Altogether, this work makes available to the international scientific community a consistent liquefaction database for in-depth earthquake studies. [ABSTRACT FROM AUTHOR]

Seismic hazard maps from probabilistic seismic hazard analysis or PSHA collect, at different sites, the values of the (site-specific) ground motion intensity measures of interest that, taken individually, have the same exceedance return period. For large-scale analyses, a widely used intensity measure is the macroseismic (MS) intensity, that provides an assessment of the earthquake effect based on the observed consequences in the hit area. Hazard maps can be developed in terms of MS intensity, and some examples exist in this respect. In the case of Italy, the last MS hazard map is based on the same seismic source model (known as MPS04) adopted to derive the design seismic actions of the current building code, a study dating more than ten years ago. It provides results in terms of countrywide Mercalli–Cancani–Sieberg (MCS) intensity level with 475 years return period. This short paper presents and discusses MCS probabilistic seismic hazard maps for Italy based on a recent grid-seismicity source model, herein named MPS19, synthetizing the large effort of a wide scientific community. The results, which are obtained by means of classical PSHA, are given in the form of maps referring to the 475 years return period, and also others of earthquake engineering interest. Moreover, it is discussed that the return period does not univocally identifies the MS intensity because, although MS is, by definition, a discrete random variable, it is modelled, in a given earthquake, by means of a normal distribution, that is, treated as continuous. Thus, the maps of the minimum return period causing the occurrence or exceedance of different MCS intensities are also provided. Finally, the comparison between the 475 years return period hazard map presented and the one which is currently the point of reference in Italy, that is, computed using MPS04, is briefly discussed. All the computed maps are made available to the reader as supplemental material. [ABSTRACT FROM AUTHOR]

The existing precast reinforced concrete structures not specifically designed against earthquakes have proved to be very sensitive to seismic demands. After the lesson learnt from the Emilia earthquake of May 2012, causing many collapses and severe damage, reliable seismic design criteria have been established for the design of new precast structures and for the strengthening of the existing ones. Despite this, a large percentage of the existing precast buildings in the Italian territories actually has not been object of interventions and remains in an unsafe condition with regard to the seismic actions. In this context, the methods for a rapid seismic assessment can be very helpful both to estimate the current safety level of large building stocks and to plan the necessary strengthening interventions, possibly at the large scale of an industrial area. To this aim, the paper proposes the PRESSAFE-disp (PRecast Existing Structure Seismic Assessment by Fast Evaluation-displacements) method, useful for the fast evaluation of the fragility curves of precast structures. The damage criteria, applicable both to structural elements and non-structural cladding elements on the perimeter, have been selected in order to capture the damage mechanisms observed during the building inspections conducted by the authors in the aftermath of the 2012 Emilia earthquakes. The method allows a comprehensive explanation of the seismic in-plane behaviour of existing precast RC buildings and could be effectively adopted, for example, in earthquake loss estimations and seismic risk assessments of large Italian industrial areas, as well as of wide seismic-prone territories of the Mediterranean area. [ABSTRACT FROM AUTHOR]

By comparing damage and loss predictions with those observed for a 22-storey steel building with eccentrically based frames (EBF) that underwent the Canterbury earthquakes, this paper gauges the performance and explores the benefits of applying the PEER performance-based earthquake engineering assessment procedure. The study shows that steel EBF repair costs are significantly affected by the work required to remove and reinstate non-structural elements in order to access the steel structure. It is therefore concluded that the location of non-structural elements relative to structural elements should be considered in the seismic design of new buildings and within loss assessment procedures. Two retrofit and/or rehabilitation options are considered for the building; improving the deformation capacity of drywall partitions, and re-detailing the exterior cladding connections to better accommodate structural deformations. The findings show that, for the specific building, improving the drywall partitions should lead to a reduction in expected annual losses whereas the use of improved detailing for the precast concrete cladding would not. This suggests a general strategy for cost-effective decisions might be to focus on increasing the performance of the most vulnerable components (plasterboard partition walls, in this case). An examination of the potential effects of aftershocks to the selection of cost-effective options adds support to this conclusion. Aftershocks are found to increase the predicted losses by around 10%, emphasizing the need to consider aftershocks when assessing expected annual losses due to earthquakes. [ABSTRACT FROM AUTHOR]

The earthquake sequence started on May $$20$$ th 2012 in Emilia (Italy) affected a region where masonry constructions represent a large part of the existing building stock and the construction of new modern masonry buildings is a common practice. The paper is focused on the performance of common architectural configurations, typical for residential or business use. The large majority of old masonry buildings is made of fired clay bricks. The seismic performance of these buildings is particularly interesting since major past earthquakes in Italy affected areas with mainly stone masonry structures. Apart from examples showing systematic or peculiar structural deficiencies governing the vulnerability of several buildings, the overall seismic performance of these structures to repeated shaking, with PGA as large as 0.25-0.3 g was rather good, despite the major part of them were only conceived for carrying vertical loads. In fact, seismic design is mandatory in the area only since 2003. Modern low-rise masonry buildings erected after this date and incorporating seismic design and proper detailing resulted in most cases practically undamaged. The examples reported in the paper allow an evaluation of the superior performance of seismically designed modern masonry buildings in comparison to older ones. [ABSTRACT FROM AUTHOR]

Residual risk exists in our buildings even if they were designed in conformance with modern codes of practice. Various approaches have been implemented or proposed in the last decade for setting risk-based performance requirements for seismic design of building structures. However, there is insufficient consideration about the aggregated risk for society, which could be significant especially for a densely populated metropolitan city. This paper introduces a rational and universal approach for evaluating the adequacy of structural safety requirements by comparing societal risk functions based on probabilistic loss assessment with a proposed regulatory requirement that aims to limit the mortality rate to "as low as reasonably practicable (ALARP)". The proposed approach is then applied to Melbourne, Australia, in a case study, which shows that the earthquake fatality risk for the society appears to be unacceptable. The outcome can be used for justification of a seismic retrofitting policy or a required change of the design code level. The proposed scheme is also applicable to other natural hazards and for safety engineering applications generally. [ABSTRACT FROM AUTHOR]

The assessment of maximum displacement demand is a crucial point in the design of seismic isolating systems, in particular when the non linear behaviour of devices is modeled through visco-elastic equivalent schemes, as common in the design practice. Several phenomena influence the maximum demand assessment, among which the torsional and earthquake directionality effects can be of great impact. International codes use some formulations which allow to consider torsional effects, while the impact of the other phenomena is commonly assessed through time-history analyses. In this paper an innovative design method is developed based on an exact linear elastic formulation with response spectrum, which keeps in count both torsional and directivity effects considering natural and accidental eccentricity and by using the CQC3 (Menun and Der Kiureghian in Earthq Spectra 153–163, 1998. 10.1193/1.1586025) as directional combination rule. The method models the seismic action through the response spectra of a set of natural recorded ground motions, properly oriented along their principal axes to assess the correct ratio between the horizontal components of spectral accelerations; thus accounting for the site-specific earthquake source, without the need to perform time-history analyses. A specific formalization of the dynamic problem is presented to emphasize the parameters which more affects the response (e.g. torsional factor, eccentricity, geometrical aspect ratio) and simplify its interpretation. Results obtained on two case studies are compared with time-history analyses to show the effectiveness of the procedure. [ABSTRACT FROM AUTHOR]

Non-structural elements represent most of the total construction cost of typical buildings. A significant portion of the total losses in recent earthquakes worldwide, has been attributed to damage to non-structural elements. Damage to non-structural elements occurs at low levels of ground shaking, and can significantly affect the post-earthquake functionality of buildings. However, in Europe, limited prescriptions are provided in the codes for seismic design of non-structural elements and this may partially explain why it is so common for these elements to perform poorly during earthquakes. This paper describes the observed damage to non-structural elements following the 2016 Central Italy earthquake. The most commonly damaged elements were partition walls, ceiling systems, non-structural vaults, chimneys, and storage racks. As a result, it was highlighted the need to introduce seismic regulations devoted to improving the seismic performance of non-structural elements and to reduce the associated economic losses, loss of functionality, and potential threats to life safety. [ABSTRACT FROM AUTHOR]

Historical earthquakes in developing countries, particularly in South America, have caused devastating effects in essential buildings, such as hospitals. As a result, some structural retrofits and new designs of essential facilities in South American countries have concentrated on increasing the seismic design forces beyond what is normally required by building codes. This increased-strength approach can lead to quasi-elastic structural response during earthquakes with much larger induced floor accelerations than expected from code-designed structures. In critical structures, sub-par performance of critical non-structural elements, such as medical equipment in a hospital, due to high-induced floor accelerations can have consequences as devastating as structural failures. Passive seismic protection systems, such as seismic isolation, provide a practical means of controlling seismic demand and are now common in developed countries. However, the applications of protection systems have been far fewer in developing countries due to economic considerations and lack of technical expertise. This paper presents the experimental and numerical studies supporting the development of a novel low-cost sustainable protection system incorporating recycled automobile tires for isolating designated floors or rooms in essential buildings in developing countries. The main innovation of the proposed floor isolation system is the geometric arrangement of the rubber tires that allows isolation from both, horizontal and vertical floor accelerations. Horizontal and vertical cyclic testing conducted on tire specimens are first described followed by the development of a numerical model able to reproduce the experimental results. Finally, an existing case-study hospital in Ecuador is considered for evaluating numerically the seismic performance of the proposed floor isolation system. [ABSTRACT FROM AUTHOR]

The evaluation of realistic time histories for various locations around Marmara Region is aimed to provide reliable input for performance-based seismic design, hazard or risk management studies and developing new seismic standards. The applicability of empirical Green’s functions methodology and physics-based solution of earthquake rupture have been assessed in terms of modeling complex geologic structures. This paper has two main objectives. The first one is to simulate five medium-size magnitude earthquakes (Mw ≈ 5.0) recorded in the Marmara Region. A series of synthetic ground motion waveforms for three components are evaluated with a ‘physics-based’ solution of earthquake rupture. The simulation methodology is based on the studies of Hutchings and Wu (J Geophys Res 95:1187-1214, 1990), Hutchings (Seismol Soc Am 81:88-121, 1991; Seismol Soc Am 84:1028-1050, 1994), Hutchings et al. (Geophys J Int 168:569-680, 2007), and Scognamiglio and Hutchings (Tectonophysics 476:145-158, 2009). For each earthquake, we calculate synthetic seismograms by using 500 different rupture scenarios that are generated by Monte Carlo method for a selection of parameters within a range based on prior knowledge of where the earthquakes will occur. The second objective is to validate synthetic seismograms with real seismograms. To improve the credibility of synthetic seismograms from an engineering point of view, the methodology presented by Anderson (in 13th world conference on earthquake engineering, Vancouver, 2003) is followed. This methodology proposes a similarity score based on averages of the quality of fit measuring ground motion characteristics and uses a suite of measurements. In order to compute goodness of fit, ten different ground motion parameters were compared on a scale from 0 to 100, where 100 means perfect agreement. Because the methodology produces source- and site-specific synthetic ground motion time histories, and the goodness-of-fit scores of obtained synthetics are between ‘good’ and ‘excellent’ range (61.128-82.164) based on the Anderson’s score, we conclude that it can be used to produce reliable ground motion time histories for seismic risk regions to develop or improve seismic codes and standards. [ABSTRACT FROM AUTHOR]

In this paper economic seismic risk analysis of API 5L buried steel gas pipelines is carried out through incremental dynamic analysis using an ensemble of 20 ground motion records. Multiple performance limit states for buried steel pipelines are proposed. Fragility curves of 15 pipeline models of various diameter to thickness (D/t) ratios, burial depth to diameter (H/D) ratios, assumed soil conditions and steel grades are plotted for damage states corresponding to the defined limit states. Expected global economic loss of 1 km length of the pipelines for a given peak ground velocity is obtained using the fragility curves, a pipeline repair ratio as well as costs of leakage repairing and break-induced pipe replacement. The mean annual frequency of exceedance of loss for the investigated pipelines is calculated using a seismic hazard curve and the expected annual loss (EAL) is obtained. It is concluded that in case of the pipelines with the D/t ratio greater than 39.9, the probabilities of failure for a given return period increase with increasing D/t ratio. It is obtained that the probabilities of failure for a given return period increase with increasing H/D ratio and shear modulus of the soil (Gs). The results show that the probabilities of failure decrease with increasing steel grade of the pipes. It is found that for a given return period, the global economic loss increases for an increase in the D/t, H/D and Gs values. The results show that EAL of the pipelines decreases with increasing steel grade of the pipes and decreasing D/t ratio, H/D ratio as well as Gs value. It is obtained that frequency of exceedance of a given loss value increases with an increase in D/t, H/D and Gs values. It is noteworthy that the obtained results are valid only for Tehran, and the pipe and soil characteristics used in the study. [ABSTRACT FROM AUTHOR]

The paper introduces a number of new analytic techniques and practical technologies that lead to the development of an efficient earthquake resistant system. The proposed structural system consists of a grade beam supported moment frame connected to a rigid rocking core through story level rigid links. The new system tends to bend and tilt as an upright simply supported beam with minimal uniform drift and prevents the formation of soft story failure within the moment frame. It is capable of preventing severe damage to its columns and footings and can be equipped to prevent catastrophic collapse due to strong ground motion and re-center itself afterwards. The analytic development is based on global, design led analysis and results in closed form, exact solutions that are highly suitable for preliminary, manual, as well as spread sheet computations. Several examples have been provided to verify and demonstrate the applications of the proposed formulations. All numerical results have been verified by independent computer analysis. [ABSTRACT FROM AUTHOR]

This paper proposes a modification of the empirical method for seismic vulnerability assessment of reinforced concrete buildings in urban areas. In the RISK-UE LM1 framework, the values of the behaviour modifiers related to: (i) the level of seismic code design; (ii) the number of storeys above ground; and (iii) the structural joint between adjoining buildings, have been modified according to an analysis of the actual seismic performance of buildings and a review of the currently available models, providing continuity to the progress of the previous works published to date. The new model has been applied to the city of Lorca, Spain following the damage data from the earthquake of May 11, 2011. Less dispersion between actual observed and estimated damage in buildings is presented in comparison with the previous studies, with a statistical significance level of 5%, thus achieving a more accurate evaluation of seismic risk based on the typological, structural and urban parameters of the buildings. Nevertheless, future work to further improve these modifiers is necessary in order to achieve a better adjustment between the estimated and observed damage. By using GIS techniques, the proposal can also be used to develop the planning and management of post-earthquake emergency situations, allowing for a better definition of several damage scenarios. [ABSTRACT FROM AUTHOR]

In seismic design of extended multi-span bridges the question always arises whether using either natural or artificially generated earthquake records that are identical at all bridge supports is valid or not. It is likely that earthquake ground motion remarkably differs at the various support/pier locations in terms of amplitude, frequency content and arrival time, inducing under certain circumstances significant forces and deformations that would not develop if the assumption of synchronous excitation was adopted. This paper hence illustrates the impact of ground motion spatial variability on the seismic performance and vulnerability of extended continuous box girder bridges in both bridge orthogonal directions (longitudinal and transverse). For illustration purposes, a nine-span bridge with a total length of 430 m is adopted. Non-linear time history analyses are carried out using opensees software. The effects of the spatial variability in the ground motions at the different bridge supports are investigated using a set of 20 artificially simulated seismic ground motions generated using sim software developed in the mid-nineties, considering different degrees of loss in coherency and various soil types (i.e., frequency contents). Results of the non-linear time history analyses performed in an incremental dynamic analysis context are hence manipulated through a probabilistic analysis framework to generate fragility curves associated with various performance levels for the case study bridge. Fragility curves giving the conditional probability of exceeding various performance levels are then integrated with generated hazard curves defining the expected seismic hazard in Egypt. The outcome of this integration process results in values of mean annual frequency of exceeding pre-defined performance levels. [ABSTRACT FROM AUTHOR]