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Showing papers in "Journal of Earthquake Engineering in 2004"


Journal ArticleDOI
TL;DR: In this article, the authors present guidelines on procedures for the selection of appropriate suites of acceleration time-series for the purpose of dynamic analysis in geotechnical and structural engineering.
Abstract: The increasing availability of strong-motion accelerograms, and the relative ease with which they can be obtained compared to synthetic or artificial records, makes the use of real records an ever more attractive option for defining the input to dynamic analyses in geotechnical and structural engineering. Guidelines on procedures for the selection of appropriate suites of acceleration time-series for this purpose are lacking, and seismic design codes are particularly poor in this respect. Criteria for selecting records in terms of earthquake scenarios and in terms of response spectral ordinates are presented, together with options and criteria for adjusting the selected accelerograms to match the elastic design spectrum. The application of both geophysical and response spectral search criteria is illustrated using compatible scenarios, and the selected records are analysed and adjusted to produce suites of acceleration time-series suitable for dynamic analyses. The paper concludes with suggestions for mak...

483 citations


Journal ArticleDOI
TL;DR: In this article, a displacement-based adaptive pushover procedure is presented, whereby a set of laterally applied displacements, rather than forces, is monotonically applied to the structure, and the integrity of the analysis algorithm is veried through an extensive comparative study involving static and dynamic nonlinear analysis of 12 reinforced concrete buildings subjected to four diverse acceleration records.
Abstract: In this paper, an innovative displacement-based adaptive pushover procedure, whereby a set of laterally applied displacements, rather than forces, is monotonically applied to the structure, is presented. The integrity of the analysis algorithm is veried through an extensive comparative study involving static and dynamic nonlinear analysis of 12 reinforced concrete buildings subjected to four diverse acceleration records. It is shown that the new approach manages to provide much improved response predictions, throughout the entire deformation range, in comparison to those obtained by force-based methods. In addition, the proposed algorithm proved to be numerically stable, even in the highly inelastic region, whereas the additional modelling and computational eort, with respect to conventional pushover procedures, is negligible. This novel adaptive pushover method is therefore shown to constitute an appealing displacement-based tool for structural assessment, fully in line with the recently introduced deformation- and performanceoriented trends in the eld of earthquake engineering.

342 citations


Journal ArticleDOI
TL;DR: In this paper, the accuracy of adaptive pushover methods in predicting the horizontal capacity of reinforced concrete buildings is explored, through comparison with results from a large number of nonlinear time-history dynamic analyses.
Abstract: The recent drive for use of performance-based methodologies in design and assessment of structures in seismic areas has significantly increased the demand for the development of reliable nonlinear inelastic static pushover analysis tools. As a result, the recent years have witnessed the introduction of the so-called adaptive pushover methods, which, unlike their conventional pushover counterparts, feature the ability to account for the effect that higher modes of vibration and progressive stiffness degradation might have on the distribution of seismic storey forces. In this paper, the accuracy of these force-based adaptive pushover methods in predicting the horizontal capacity of reinforced concrete buildings is explored, through comparison with results from a large number of nonlinear time-history dynamic analyses. It is concluded that, despite its apparent conceptual superiority, current force-based adaptive pushover features a relatively minor advantage over its traditional non-adaptive equivalent, particularly in what concerns the estimation of deformation patterns of buildings, which are poorly predicted by both types of analysis.

227 citations


Journal ArticleDOI
TL;DR: In this article, the authors present the results of a study on the engineering characteristics of vertical ground motion and present a ground-motion model for the vertical-to-horizontal ratio (V/H) of peak ground acceleration.
Abstract: This paper presents the results of a study on the engineering characteristics of vertical ground motion. A ground-motion model for the vertical-to-horizontal ratio (V/H) of peak ground acceleration...

216 citations


Journal ArticleDOI
TL;DR: In this paper, nonlinear time domain site response analysis is used to capture the soil hysteretic response and nonlinearity due to medium and large ground motions, and soil damping is captured primarily through the...
Abstract: Nonlinear time domain site response analysis is used to capture the soil hysteretic response and nonlinearity due to medium and large ground motions. Soil damping is captured primarily through the ...

181 citations


Journal ArticleDOI
TL;DR: Shape memory alloys (SMAs) are a class of materials that have unique properties, including Young's modulus-temperature relations, shape memory effects, superelastic effects, and high damping characteristics as mentioned in this paper.
Abstract: Shape memory alloys (SMAs) are a class of materials that have unique properties, including Young's modulus-temperature relations, shape memory effects, superelastic effects, and high damping characteristics. These unique properties, which have led to numerous applications in the biomedical and aerospace industries, are currently being evaluated for applications in the area of seismic resistant design and retrofit. This paper provides a critical review of the state-of-the-art in the use of shape memory alloys for applications in seismic resistant design. The paper reviews the general characteristics of shape memory alloys and highlights the factors affecting their properties. A review of current studies show that the superelastic and high-damping characteristics of SMAs result in applications in bridges and buildings that show significant promise. The barriers to the expanded use of SMAs include the high cost, lack of clear understanding of thermo-mechanical processing, dependency of properties on temperat...

176 citations


Journal ArticleDOI
TL;DR: In this paper, a number of purely observational studies demonstrate that ground motions have large site-to-site variability for a single earthquake and large earthquake-location-dependent variability in a single site.
Abstract: Large modifications of seismic waves are produced by variations of material properties near the Earth's surface and by both surface and buried topography. These modifica-tions, usually referred to as “site response”, in general lead to larger motions on soil sites than on rock-like sites. Because the soil amplifications can be as large as a factor of ten, they are important in engineering applications that require the quantitative spec-ification of ground motions. This has been recognised for years by both seismologists and engineers, and it is hard to open an earthquake journal these days without finding an article on site response. What is often missing in these studies, however, are discussions of the uncertainty of the predicted response. A number of purely observational studies demonstrate that ground motions have large site-to-site variability for a single earthquake and large earthquake-location-dependent variability for a single site. This variability makes site-specific, earthquake-specific predi...

129 citations


Journal ArticleDOI
TL;DR: In this paper, the authors derived a yield period-height formula for use in displacement-based assessment of European buildings using analytical fiber element models of RC frames of varying height and the yield period has been sought using eigenvalue, pushover and dynamic analyses.
Abstract: Simple empirical relationships are available in many design codes to relate the height of a building to its fundamental period of vibration. These relationships have been realised for force-based design and so produce conservative estimates of period such that the lateral shear force will be conservatively predicted from an acceleration spectrum. Where assessment of a structure is concerned, however, it is the displacement demand that gives an indication of the damage that can be expected; this displacement would be underestimated with the use of the aforementioned period-height formulae. Furthermore, the period of vibration of interest in assessment is the yield period, which is calculated using the yield stiffness, also often referred to as the cracked or elastic stiffness. The derivation of a yield period-height formula for use in displacement-based assessment of European buildings is thus the focus of this work. Analytical fibre element models of RC frames of varying height have been developed and the yield period has been sought using eigenvalue, pushover and dynamic analyses.

121 citations


Journal ArticleDOI
TL;DR: In this paper, the capacity curve of a structure with respect to the roof displacement is established, and a nonlinear static method of analysis is used to determine the capacity of the structure.
Abstract: Existing nonlinear static (pushover) methods of analysis establish the capacity curve of a structure with respect to the roof displacement. Disproportionate increases in the roof displacement, and ...

110 citations


Journal ArticleDOI
TL;DR: In this paper, the importance of including the vertical component of earthquake ground motion in seismic analysis and design was highlighted, and pioneering studies [e.g., Elnashai and Papa...
Abstract: Recent research clearly shows the importance of including the vertical component of earthquake ground motion in seismic analysis and design. In addition, pioneering studies [e.g., Elnashai and Papa...

102 citations


Journal ArticleDOI
TL;DR: In this paper, the first and second peaks and the first trough in the H/V spectra are used in a simple resonance model to estimate depths of the bedrock in the Lower Rhine Embayment.
Abstract: In recent years, H/V measurements have been increasingly used to map the thickness of sediment fill in sedimentary basins in the context of seismic hazard assessment. This parameter is believed to be an important proxy for the site effects in sedimentary basins (e.g. in the Los Angeles basin). Here we present the results of a test using this approach across an active normal fault in a structurally well known situation. Measurements on a 50 km long profile with 1 km station spacing clearly show a change in the frequency of the fundamental peak of H/V ratios with increasing thickness of the sediment layer in the eastern part of the Lower Rhine Embayment. Subsequently, a section of 10 km length across the Erft-Sprung system, a normal fault with ca. 750 m vertical offset, was measured with a station distance of 100 m. Frequencies of the first and second peaks and the first trough in the H/V spectra are used in a simple resonance model to estimate depths of the bedrock. While the frequency of the first peak shows a large scatter for sediment depths larger than ca. 500 m, the frequency of the first trough follows the changing thickness of the sediments across the fault. The lateral resolution is in the range of the station distance of 100 m. A power law for the depth dependence of the S-wave velocity derived from down hole measurements in an earlier study [Budny, 1984] and power laws inverted from dispersion analysis of micro array measurements [Scherbaum et al., 2002] agree with the results from the H/V ratios of this study.

Journal ArticleDOI
TL;DR: In this paper, a time-domain parametric study for the seismic response of a region located on the eastern bank of the Kifisos river canyon is performed to evaluate the significance of topography and soil effects on the seismic responses of slopes.
Abstract: A time-domain parametric study for the seismic response of a region located on the eastern bank of the Kifisos river canyon is performed to evaluate the significance of topography and soil effects on the seismic response of slopes. This region experienced unexpectedly heavy damage during the 7 September 1999 M_s 5.9 earthquake. Two-dimensional finite-element and spectral-element analyses are conducted using Ricker wavelets of various central frequencies as horizontal and vertical base excitation. The significance of a layered soil profile and the frequency content of the input motion, the emergence of "parasitic" acceleration components, and the effect of the angle of incidence on the amplification of the incoming waves are all discussed in detail. It is shown that the presence of a surface soil layer significantly affects the amplification pattern. The so-called Topographic Aggravation Factor (defined as the 2D/1D Fourier spectral ratio) achieves its maximum value very near the crest, in function of the frequency content of the excitation. For the particular soil conditions and geometry analysed, vertically propagating SV waves incite at about the critical angle, resulting in the highest topographic amplification.

Journal ArticleDOI
TL;DR: In this article, a strain rate independent, phenomenological model is presented which effectively represents the stiffness, damping, and degradation response of high-damping rubber (HDR) bearings.
Abstract: High-damping rubber (HDR) bearings are used in seismic isolation applications for buildings and bridges, although no models are currently available for the accurate description of the shear force-deformation response under bidirectional loading. A strain rate-independent, phenomenological model is presented which effectively represents the stiffness, damping, and degradation response of HDR bearings. The model decomposes the resisting force vector as the sum of an elastic component in the direction of the displacement vector and a hysteretic force component parallel to the velocity vector. The elastic component is obtained from a generalised Mooney—Rivlin strain energy function, and the hysteretic component is described by an approach similar to bounding sur-face plasticity. Degradation is decomposed into long term (“scragging”) and short term (“Mullins' effect”) components. Calibration is carried out over a series of bidirectional test data, and the model is shown to provide a good match of slow strain-r...

Journal ArticleDOI
TL;DR: In this article, the authors investigated the dynamic performances of multi-degree-of-freedom shear-type structures equipped with manufactured viscous dampers and found that the mass proportional damping (MPD) matrix provides the best overall performance in terms of minimum top-storey response variance to a Gaussian band limited white noise input.
Abstract: In this paper the authors investigate the dynamic performances of multi-degree-of-freedom shear-type structures equipped with manufactured viscous dampers The system of added viscous dampers that leads to a mass proportional damping (MPD) matrix is identified as the one providing the best overall performance in terms of minimum top-storey response variance to a Gaussian band limited white noise input within the class of classically damped systems A performance index developed by the authors and based upon modal damping ratios confirms that, within the class of Rayleigh damping systems, the MPD limiting case provides the largest damping effect For a 6-dof system, a comparison with results available in literature also shows that the MPD system provides better performance than optimised (as suggested by other research works) non-classical damping schemes A physical explanation for the optimum damping performance offered by MPD systems is also provided herein, together with clear indications about how

Journal ArticleDOI
TL;DR: In this paper, a complex mode superposition method for the seismic responses of general multiple degrees of freedom (MDOF) discrete system with complex eigenvectors and eigenvalues was proposed.
Abstract: This paper deals with a complex mode superposition method for the seismic responses of general multiple degrees of freedom (MDOF) discrete system with complex eigenvectors and eigenvalues. A delicate general solution, completely in real value form, for calculating seismic time history response of the MDOF system which cannot be uncoupled by normal modes, is deduced based on the algorithms of the complex superposition method. This solution comprises of two parts which are in relation to the Duhamel integration to sine and cosine function respectively. The related term of the Duhamel integration to sine function is actually the displacement response of the oscillator with corresponding modal frequency and the damping ratio. The other can be transferred into a combination of the displacement and velocity responses of the same oscillator. In order to meet the practical needs of seismic design based on code design spectra for various kinds of structures equipped by viscous dampers, the complex complete quadratic combination (CCQC) method is deduced following similar procedures such as the well-known CQC method, in which a new modal velocity correlation coefficient, together with a new modal displacement-velocity correlation coefficient are involved besides the modal displacement correlation coefficient in normal CQC formula. The new algorithm of CCQC is not only as concise as that of the normal CQC but also has explicit physical meaning. The results obtained from complex mode superposition approaches are discussed and verified in some examples through step by step integration computation under a prescribed earthquake motion input. From these examplary analyses, it may be pointed that the CCQC algorithm normally yields conservative outcome and that the forced mode uncoupling approach has good approximation even the discussed examplary structures are strongly non-proportional.

Journal ArticleDOI
TL;DR: An extensive program of shaking table tests on 1/4-scale three-dimensional R/C frames was jointly carried out by the Department of Structure, Soil Mechanics and Engineering Geology (DiSGG) of the U...
Abstract: An extensive program of shaking table tests on 1/4-scale three-dimensional R/C frames was jointly carried out by the Department of Structure, Soil Mechanics and Engineering Geology (DiSGG) of the U...

Journal ArticleDOI
TL;DR: In this article, the authors deal with the seismic assessment of hollow bridge piers strengthened with fiber-reinforced polymer (FRP) by means of a parametric analysis considering different fibres and geometrical parameters applied to typical case studies.
Abstract: The research work presented in this paper deals with the seismic assessment of hollow bridge piers strengthened with fibre-reinforced polymer (FRP). The scope of the strengthening is to overcome some common deficiencies derived from the use of non-seismic design rules, which can often lead to inadequate response when operating in cyclic loading. The strengthening design was studied by means of a parametric analysis considering different fibres and geometrical parameters applied to typical case studies. Quasi-static cyclic tests were performed on five 1:4 scaled piers designed according to old non-seismic Italian codes and strengthened according to the previous analytical study. Efficiency of FRP strengthening was evaluated by comparing the experimental results with those obtained in a previous experimental research performed on similar non-strengthened specimens. Base shear versus lateral deflection curves, dissipated energy and collapse mechanisms comparison shows the achievable effectiveness once the debonding risk has been overcome.

Journal ArticleDOI
TL;DR: In this paper, the authors define a rational procedure for seismic vulnerability assessment of standardised industrial constructions in a probabilistic framework, which covers a range of components of the same structural type.
Abstract: National and international regulatory standards require industrial risk assessment, taking into account natural hazards including earthquakes, in the framework of Quantitative Risk Analysis (QRA). Seismic fragility analysis of industrial components may be carried out similarly as what has been done for buildings, even though some peculiar aspects require the development of specific tools. In the present paper a contribution to the definition of a rational procedure for seismic vulnerability assessment of standardised industrial constructions in a probabilistic framework is given. The method covers a range of components of the same structural type. Seismic reliability formulation for structures is used. Both seismic capacity and demand are considered probabilistic with the latter assessed by dynamic analyses. The application example refers to shell elephant foot buckling of unanchored sliding tanks. A regression-based method is applied to relate fragility curves to parameters varying in the domain of varia...

Journal ArticleDOI
Abstract: This paper presents the seismic hazard assessment and seismic zoning of the United Arab Emirates (UAE) and its surroundings based on the probabilistic approach. The area that has been studied lies ...

Journal ArticleDOI
TL;DR: In this article, it was shown that no strong earthquake has ever occurred during a certain period of time, and the mechanical behaviour of spines has not been studied in the literature.
Abstract: Is it really plausible that earthquakes break speleothems? May unbroken speleothems prove that no strong earthquake has ever occurred during a certain period of time? The mechanical behaviour of sp...

Journal ArticleDOI
TL;DR: In this article, the effects of axial load variations on the seismic response of bridges isolated with friction pendulum systems (FPSs) are investigated, and a series of parametric time history non-linear analyses are performed for different bridge configurations.
Abstract: The effects of the axial load variations on the seismic response of bridges isolated with friction pendulum systems (FPS) are investigated. A series of parametric time history non-linear analyses are performed for different bridge configurations, defined after an extensive investigation on typical existing cases. The influence of both horizontal and vertical components of the ground motion is considered. The behaviour of the pier-isolator-deck system is predicted using two analytical models characterised by hysteretic loops sensitive or insensitive to axial force variations, in order to compare the different responses. Level of axial force, maximum displacements and induced bending moment are investigated, as well as shear and torsion demand, caused by different shear actions acting on the isolator devices. A comparison between demand and resistance capacity of the bridge piers is performed, in order to investigate possible non-conservative approaches in the current design methods and to raise controversi...

Journal ArticleDOI
TL;DR: In this paper, the three dimensional pounding phenomenon of two adjacent buildings during earthquakes with aligned rigid horizontal diaphragms is investigated for the linear and nonlinear structural response, taking into account three dimensional dynamic contact conditions for the velocities and accelerations based on the impulse-momentum relationship, using the coefficient of restitution e and the ratio μ, of tangential to normal impulses.
Abstract: The three dimensional pounding phenomenon of two adjacent buildings during earthquakes with aligned rigid horizontal diaphragms is investigated for the linear and nonlinear structural response. The developed formulation takes into account three dimensional dynamic contact conditions for the velocities and accelerations based on the impulse-momentum relationship, using the coefficient of restitution e and the ratio μ, of tangential to normal impulses, which corresponds to the coefficient of friction under certain conditions. The contact points are determined geometrically from the displacements of the diaphragms' centre of mass. The results of the proposed formulation are compared with those obtained with the Lagrange multipliers approach. Test results are performed for two sets of multi-storey adjacent buildings subjected to real earth-quake motions with elastic and inelastic structural response.

Journal ArticleDOI
TL;DR: In this paper, an approach devoted to quickly assessing the thickness of soft sedimentary cover in areas of unknown subsurface morphology is applied in order to estimate the soil thickness (h).
Abstract: An approach devoted to quickly assess the thickness of soft sedimentary cover in areas of unknown subsurface morphology is applied in this study. In particular, soil thickness (h) is derived by com...

Journal ArticleDOI
TL;DR: In this paper, the effect of the dominant frequency of ground motion on the optimum parameters and effectiveness of multiple tuned mass dampers with identical stiffness and damping coefficient but with unequal mass was examined.
Abstract: Utilising the Kanai-Tajimi and Clough-Penzien spectrums and the pseudo-excitation algorithm in the frequency domain, parametric study is performed to examine the effect of the dominant frequency of ground motion on the optimum parameters and effective-ness of multiple tuned mass dampers (MTMD) with identical stiffness and damping coefficient but with unequal mass. The examination of the optimum parameters is con-ducted through the minimisation of the minimum values of the maximum displacement and acceleration dynamic magnification factors of the structure with the MTMD. The optimum parameters of the MTMD include the optimum frequency spacing reflecting the robustness, the average damping ratio and the tuning frequency ratio. Minimisation of the minimum values of the maximum displacement and acceleration dynamic mag-nification factors, nondimensionalised respectively by the maximum displacement and acceleration dynamic magnification factors of the structure without the MTMD, is used to measure the effectiv...

Journal ArticleDOI
TL;DR: In this article, the authors evaluated the non-linear behavior of non-ductile reinforced concrete short columns under lateral cyclic deformations and evaluated rehabilitation schemes using carbon fiber reinforced polymers (CFRP).
Abstract: Non-ductile response of structural elements, particularly columns, has been the cause of numerous documented failures during earthquakes. The objective of this experimental study was to evaluate the non-linear behaviour of non-ductile reinforced concrete short columns under lateral cyclic deformations and to evaluate rehabilitation schemes. Three reinforced concrete short columns were tested under cyclic lateral loads and constant axial load. The behaviour and effectiveness of different rehabilitation systems using carbon fibre reinforced polymers (CFRP) were investigated. Two different techniques to improve concrete confinement were used in the two rehabilitated specimens. It was found that it is possible to eliminate the non-ductile modes of failure of short column using anchored CFRP wraps. In addition, an analytical model to predict the confining effect and the total shear resistance of rectangular reinforced concrete columns with anchored fibre wraps was introduced. The confinement model is an extens...

Journal ArticleDOI
TL;DR: In this paper, a simple shear beam model is used to model the landfill resonant behavior and to estimate the landfill stiffness and damping properties by minimising the difference between computed and recorded acceleration response spectra at the landfill top.
Abstract: Assessment of landfill seismic response necessitates the availability of reliable dynamic material properties. During the past decade, geophysical surveys and computational studies have been conducted to investigate the seismic response of the Operating Industries, Inc. (OII) landfill in Southern California. In this paper, a survey and summary of available research results is presented. In addition, a set of OII input-output seismic records during six earthquakes is thoroughly analysed. Spectral analyses are conducted to shed light on the landfill dynamic response characteristics. A simple shear beam model is found to be useful in modelling the landfill resonant behaviour. System identification techniques are employed to estimate the landfill stiffness and damping properties. These properties are defined by minimising the difference between computed and recorded acceleration response spectra at the landfill top. The identified stiffness properties are found to be near the lower bound of those documented through geophysical measurements. Identified damping of about 5% (at resonance) is within the range of earlier investigations. Comparisons of the computed and recorded accelerations show: (i) effectiveness of a linear viscous shear beam model in simulating the landfill dynamic behaviour, for the recorded small to moderate levels of dynamic excitation (up to 0.26 g peak lateral acceleration), and (ii) potential of the employed system identification procedure for analysis of input-output seismic motions.

Journal ArticleDOI
TL;DR: In this article, the cyclic responses of four rectangular hollow section R/C bridge piers were simulated at scale 1/2.5 and tested experimentally, where both tall and short piers are considered, covering situations where bending or shear are of relevance.
Abstract: In the search for robust constitutive models suitable for reproducing the performance of bridge piers during a seismic event, this paper details the simulation of the cyclic responses of four rectangular hollow section R/C bridge piers. These four R/C bridge piers were built at scale 1/2.5 and tested experimentally. Both tall and short piers are considered, covering situations where bending or shear are of relevance. Furthermore, the four piers were reinforced according to rather different design strategies: (i) the first is a 30-year-old bridge designed without allowance to the seismic action, and (ii) the second is a bridge fulfilling the EC8 provisions. The detailed constitutive model that provides the numerical predictions includes two submodels: one with two scalar damage variables, reproducing the tensile and compressive degradations of concrete, and the other is based on the Giuffre-Menegotto-Pinto formulation, simulating the cyclic behaviour of the reinforcement. The Damage Mechanics submodel is implemented at the Gauss points of the finite elements that discretize the concrete, whereas the steel submodel is implemented on the 2-noded truss elements adopted for the rebars. A comparison between the numerical and the experimental results is discussed in detail in this paper.

Journal ArticleDOI
TL;DR: In this paper, an approach capable of synthesising strong ground motion from a basic understanding of fault mechanism and of seismic wave propagation in the Earth is applied to model the seismic input at a set of 25 sites along a chosen profile at Russe, NE Bulgaria, due to two intermediate-depth Vrancea events.
Abstract: An approach, capable of synthesising strong ground motion from a basic understanding of fault mechanism and of seismic wave propagation in the Earth, is applied to model the seismic input at a set of 25 sites along a chosen profile at Russe, NE Bulgaria, due to two intermediate-depth Vrancea events (August 30, 1986, M ω=7.2, and May 30, 1990, M ω=6.9). Accordingly to our results, once a strong ground motion parameter has been selected to characterise the ground motion, it is necessary to investigate the relationships between its values and the features of the earthquake source, the path to the site and the nature of the site. Therefore, a proper seismic hazard assessment requires an appro-priate parametric study to define the different ground shaking scenarios corresponding to the relevant seismogenic zones affecting the given site. Site response assessment is provided simultaneously in frequency and space domains, and thus the applied procedure differs from the traditional engineering approach that discu...

Journal ArticleDOI
TL;DR: An assessment of the completeness of parametric earthquake catalogues shows early journalistic sources can yield “new” earthquake data, i.e. data on previously unknown damaging earthquakes and previously unknown data on such already known events to have a high informative content.
Abstract: This study was started in the frame of an assessment of the completeness of parametric earthquake catalogues. Its primary aim was to check whether early journalistic sources can yield "new" earthquake data, i.e. data on previously unknown damaging earthquakes and previously unknown data on such already known events. Another aim was to assess the quality of the resulting information, an important matter given the widespread opinion that early journalistic sources are highly unreliable. A large sample of monographical (pamphlets) and serial (gazettes) early journalistic sources was systematically searched for "new" earthquake data. The results show them to have a high informative content, while being no more unreliable than most historical sources. It is safe to assume that a large-scale combined effort to put this informative potential within general reach would give a great impetus towards increasing the completeness of the parametric earthquake catalogues of most European (and also non-European) countries.

Journal ArticleDOI
TL;DR: In this article, the results of the seismic hazard assessment of the archaeological site of Jam using both the probabilistic explanation (PSHA) and the deterministic explanation (DSHA) approaches are presented.
Abstract: The Minaret of Jam in Afghanistan was recently included in UNESCO's List of World's Endangered Monuments. The minaret is the world's second tallest (∼60 m) after the Qutub Minar in New Delhi and it is also one of the oldest (∼800 years). It is situated at the centre of the Hindukush range in the Ghor Province at the junction of Rivers Hari-Rud and Jam-Rud, at an elevation of 1900 m. The Minaret of Jam is in danger of collapse due to a 3.4° northward inclination inducing high stresses in its deteriorated brick masonry. The precarious conditions of the monument render it highly vulnerable to earthquakes. Therefore prior to any intervention to protect it, an assessment of the seismic hazard at the site, followed by an evaluation of the tower's seismic vulnerability, is of foremost importance. This article illustrates the results of the seismic hazard assessment of the archaeological site of Jam using both the probabilistic explanation (PSHA) and the deterministic explanation (DSHA) approaches. Uncertainty in...