JournalTOCs

Bulletin of Earthquake Engineering
Journal Prestige (SJR): 1.522

Citation Impact (citeScore): 3
Number of Followers: 10

Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1573-1456 - ISSN (Online) 1570-761X
Published by Springer-Verlag

[2469 journals]

A new region-specific empirical model for prediction of ground motion
significant duration in Turkey
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  Abstract: Abstract Ground motion amplitude, frequency content, and duration are commonly identified as the main features of seismic waves affecting structural demand. Among these parameters, earthquake duration can have a substantial influence on assessment of structural seismic demand. The paper proposes a new empirical model for predicting the significant duration of ground-motion records in Turkey. Significant duration is an important parameter in determining the damage potential of earthquakes and is defined as the time interval between two specific values of Arias intensity. The proposed model is as function of moment magnitude ( \({M}_{w}\) ), Joyner-Boore distance ( \({R}_{jb}\) ), time-averaged shear-wave velocity in the top 30 m ( \({V}_{S30}\) ), and fault mechanism ( \({F}_{m}\) ). In the regression process, a database consisting of 850 records from 408 earthquakes in Turkey is used. According to the physics of the problem, mixed effect regression is employed. Next, besides residual analysis, comparison of the mean values with the other prediction models are performed. The results of this study indicate that the new model is satisfactory while reliable estimates of significant duration could be assessed for the Turkish region.
  PubDate: 2022-05-20
Probabilistic residual capacity assessment of mainshock-damaged multi-span
simply supported concrete girder bridges subjected to aftershocks
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  Abstract: Abstract Since post-mainshock events following a major earthquake are likely to occur, it is imperative to have an understanding of the functionality status of mainshock-damaged bridges to make more informed decisions. This paper examines the post-earthquake operability of a typical highway bridge class in reference to the time-varying nature of aftershock hazard by using the residual collapse capacity of the mainshock-damaged bridge. A procedure for estimating the probabilistic system-wide residual capacities to withstand aftershocks resulting from the residual capacities of vulnerable major bridge components across damage states is discussed. Based on varying earthquake scenarios, the probability of transiting to all post-mainshock and post-aftershock damage states are calculated for intact and mainshock-damaged bridges, respectively. It is observed that as the level of mainshock-sustained damage increases, the probability of experiencing more damage due to aftershocks decreases. Using the probability distribution of the intact collapse capacity or residual collapse capacity across post-mainshock damage states in combination with the mainshock and aftershock hazard curves, respectively, the annual probability of collapse for the location of interest is obtained. Having determined the intact and residual collapse capacities, as well as the site-specific mainshock and aftershock hazards, the tagging condition of the damaged bridge in the aftermath of an earthquake due to the possible future aftershocks, is evaluated by computing the equivalent constant collapse rate. The required time for imposing traffic restrictions on the mainshock-damaged bridge due to the life-safety threats in the aftershock environment is specified for various earthquake scenarios.
  PubDate: 2022-05-19
Performance of RC cast-in-place buildings during the November 26, 2019
Albania earthquake
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  Abstract: Abstract This paper documents performance of cast-in-place reinforced concrete (RC) buildings in the Durrës municipality during Albania earthquake of November 26, 2019 (MW 6.4). Both mid- and high-rise RC buildings were affected by the earthquake, experiencing structural and/or non-structural damage and even collapse in some cases. The authors performed a reconnaissance study after the earthquake and were involved in seismic assessment of buildings in the affected area. Besides the observations related to physical damage of RC buildings, the paper also presents results of a statistical analysis of damaged RC buildings in the Durrës municipality. The discussion in the paper is focused on damage patterns and failure mechanisms that are relevant for the seismic response of RC structures. Most common damage pattern observed after the earthquakes was related to masonry infill walls, which experienced damage and failure in some cases, and affected the performance of adjacent RC columns due to the infill/frame interaction. Taller RC framed buildings (10 storeys and higher) were expected to have RC shear walls; however, these walls were reportedly absent in the damaged buildings of this type. In some cases, masonry infill walls (instead of RC shear walls) were used in the elevator shaft areas, which resulted in inadequate seismic performance. A case study has been presented to illustrate seismic behaviour of mid-rise and high-rise cast-in-place RC buildings in the November 2019 earthquake, and is based on post-earthquake field observations and a detailed seismic assessment of two earthquake-damaged buildings. Finally, relevant lessons and recommendations are presented in light of the observed performance of RC buildings.
  PubDate: 2022-05-18
A non-ergodic ground-motion model of Fourier amplitude spectra for France
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  Abstract: Abstract We used an ergodic ground-motion model (GMM) of California of Bayless and Abrahamson (Bull Seismol Soc Am 109(5):2088–2105, 2019) as a backbone model and incorporated the varying-coefficient model (VCM), with a modification for anisotropic path effects, to develop a new non-ergodic GMM for France based on the French RESIF data set (1996–2016). Most of the earthquakes in this database have small-to-moderate magnitudes (M2.0 – M5.2). We developed the GMM for the smoothed effective amplitude spectrum (EAS) rather than for elastic spectral acceleration because it allows the use of small-magnitude data to constrain linear effects of the path and site without the complication of the scaling being affected by differences in the response spectral shape. For the VCM, the coefficients of GMM can vary by geographical location and they are estimated using Gaussian-process regression. There is a separate set of coefficients for each source and site coordinate, including both the mean coefficients and the epistemic uncertainty in the coefficients. We further modify the anelastic attenuation term of a GMM by the cell-specific approach of Dawood and Rodriguez-Marek (Bull Seismol Soc Am. 103 (2B): 1360–1372, 2013) and Kuehn et al. (Bull Seismol Soc Am 109 (2): 575–585, 2019) to allow for azimuth-dependent attenuation for each source which reduces the standard deviation of the residuals at long distances. As an example, we compute the 5 Hz seismic hazard for two sites using the non-ergodic EAS GMM. At the 1E-4 annual frequency of exceedance hazard level, there can be a large difference between the ergodic hazard and the non-ergodic hazard if the distance between the chosen site and the available data is smaller than the correlation length of the non-ergodic terms). The combination of the non-ergodic median ground motion and the reduced aleatory variability can have large implications for seismic-hazard estimation for long return periods. For some sites, the estimated hazard will increase and for other sites, the estimated hazard will decrease compared to the traditional ergodic GMM approach. Due to the skewed distribution of the epistemic uncertainty of the hazard, more of the sites will see a decrease in the mean hazard at the 1E−4 hazard level than will see an increase as a result of using the non-ergodic GMM.
  PubDate: 2022-05-17
Optimum weighted arithmetic means of peak- and spectral-based intensity
measures for probabilistic seismic demand modeling of modularized
suspended buildings
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  Abstract: Abstract Optimum intensity measures of ground motions have been extensively investigated in order to improve the quality of probabilistic seismic demand models. Common scalar-type intensity measures prevail in availability and computability but are less satisfactory when predicting seismic responses of systems with multiple contributing vibration modes and different forms of nonlinearity. For complex primary-secondary tuning structures, such as the modularized suspended building systems, optimal forms of scalar-type intensity measures have yet to be investigated. This study addresses this gap and particularly explores weighted arithmetic means of spectral accelerations or peak ground responses. Multi-objective optimizations of the weighting factors and the IM parameters are conducted for 5 performance indices and 10 targeted responses of a 10-story modularized suspended building on a shallow foundation when subjected to 660 ground motions. Frequency domain analysis and Pareto pattern analysis are used to interpret optimization results. It is shown that multiple elastic and elongated modes are attended to by the combination of spectral accelerations with various levels of modal periods and damping ratios, leading to a 0.22 proficiency index and a 0.96 correlation index which are 38% and 5% improvements from those of PGA. Optimal combinations of fractional order peak ground responses show distributions of derivative order between 0 and 3, achieving a 0.25 proficiency index and a 0.95 correlation index, but with notably fewer optimizing parameters.
  PubDate: 2022-05-16
Geological and geotechnical investigation of the seismic ground response
characteristics in some urban and suburban sites in Chile exposed to large
seismic threats
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  Abstract: Abstract The central area of Chile’s Valparaiso Region has been classified as a seismic gap for a major earthquake, which makes it very important to understand the seismic hazard of the zone. Generally, seismic codes consider a qualitative classification of sites to estimate the possible damage in the case of an earthquake scenario. Estimating the values of acceleration could be very important to prevent damages and increase preparedness for these rare events. In this research, a qualitative and quantitative estimation of seismic hazard is performed in the study area (Valparaiso region between Papudo and San Antonio 32°–34° S). This is achieved through an integrated and relatively economical approach which considers the information from Geology, Geophysical experiments (Gravity and seismic methods), and Geotechnical analyses. The results of the geophysical survey and geology information allow dividing the zone into five site types through a new proposal of site classification that depends not only on the Vs30, but also on the sites predominant period (T0), which is an innovation of this work for the Chilean code. The Peak Ground Acceleration (PGA) values in the study zone were estimated using a Ground Motion Predictive Equation developed for the Chilean subduction zone. Additionally, we consider three different seismic scenarios according to the history of events in Central Chile. The results of this quantitative analysis show PGA values up to 0.52 g for the median and 1.2 g for the 84th percentile of the scenarios. Overall, the highest accelerations (PGA) are in zones with low shear wave velocities (< 500 m/s), a long predominant period (> 0.4 s) and where geology establishes the presence of low stiffness soils. The comparison of response spectra from the model against records from 2010 Maule and 1985 Valparaiso earthquakes shows available models tend to overpredict the intensities.
  PubDate: 2022-05-16
Efficient non-ergodic ground-motion prediction for large datasets
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  Abstract: Abstract An efficient numerical method for non-ergodic ground-motion inference and prediction is proposed that alleviates the large computational and memory requirements associated with the traditional approach based on Gaussian Processes described in Landwehr et al. (Bull Seismol Soc Am, https://doi.org/10.1785/0120160118, 2016). The method uses the latest developments in Gaussian Processes and Machine Learning from Wilson and Nickisch (in: International Conference on Machine Learning, pp 1775–1784, 2015) (SKI) and Gardner et al. (in: International Conference on Artificial Intelligence and Statistics, pp. 1407–1416, 2018) (SKIP) and uses sparse approximations combined with efficient matrix decompositions to accurately approximate the large covariance matrices involved in the calculations. This efficient method can be used for both inference of hyperparameters of the non-ergodic ground-motion models and for forward predictions of non-ergodic median ground-motion. The application to predictions are presented. For large datasets of 100,000 to 1,000,000 ground motion values, the proposed method increases the computation speed by factors of 100 to 1000, reducing run times from days to minutes. In addition, the memory requirements are reduced from hundreds of GB to a few GB only, which makes the development of non-ergodic ground-motion models practical using traditional desktop computers.
  PubDate: 2022-05-10
Dynamic properties of polyurethane from resonant column tests for
numerical GSI study
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  Abstract: Abstract The paper focuses on the detailed analysis of the dynamic characterisation of polyurethane to evaluate the effects of polyurethane injections into soil with the aim of geotechnical seismic isolation. To determine the dynamic properties, resonant column (RC) tests were performed at the University Kore of Enna (Italy) on specimens of pure polyurethane with different values of density and subjected to different mean confining pressures. The results obtained by means of RC tests, in terms of shear modulus G and the damping ratio D as a function of shear strain γc, allowed to develop an analytical formulation for G-γc and D-γc curves, taking into account the linear relationship with density, of both the maximum value of shear modulus Gmax and the minimum value of damping ratio Dmin. The analytical formulation derived from the experimental results is applied for ground response seismic analyses of cohesive soils injected with polyurethane, using a finite element code. The numerical results show that the polyurethane injections reduce the value of maximum acceleration on the ground surface and the reduction varies with the thickness of the soil modified by polyurethane injections.
  PubDate: 2022-05-09
Pin-supported walls as seismic retrofit for existing RC frames:
feasibility and preliminary design
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  Abstract: Abstract The seismic retrofit of the existing building heritage represents an urgent issue to be faced and innovative solutions which allow to overcome renovation barriers are needed. In this scenario, pin-supported (PS) walls represent an eligible solution, enabling linearization of the deformation of the frame along its height and inhibiting soft storey collapse mechanisms. The PS wall can be connected to the existing building from outside, thereby avoiding disruption to occupants or their relocation, which are acknowledged as the main barriers to the renovation nowadays. Suitability of PS wall solutions in the seismic retrofit of the existing building stock has been investigated herein, particularly in the case of existing reinforced concrete (RC) buildings, preliminarily focusing on 2D RC frames. The paper shows the weaknesses and strengths of the PS wall solution in relation to the specific features of the considered buildings. An analytical closed-form formulation is proposed and applied as a preliminary tool to evaluate the load distribution in the existing frame and in the PS wall after the retrofit considering the first mode of vibration of the retrofitted system. The results show that, in some conditions, the application of PS walls may be detrimental to the structural response. Along with the evaluation of the effectiveness of the retrofit solution, the proposed formulation allows a preliminary design of the retrofit system. Finally, a series of finite element model analyses have been carried out for validation purposes showing a good agreement between the proposed analytical formulation and the numerical results.
  PubDate: 2022-05-06
The influence of strip load on the seismic design of cantilever sheet pile
walls: a simplified analytical solution
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  Abstract: Abstract 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.
  PubDate: 2022-04-26
Multi-platform simulation of infilled shear-critical reinforced concrete
frames subjected to earthquake excitations
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  Abstract: Abstract This paper proposes a multi-platform simulation method for the seismic performance assessment of masonry infilled reinforced concrete (RC) frames, especially for those that, due to inadequate reinforcing details, tend to undergo shear failure during an earthquake. The multi-platform method is based on a micro–macro modeling approach in which a detailed finite element model of the RC frame is incorporated with a strut model of the infill wall. It exploits the strut model to increase its computational efficiency and the finite element model based on the modified compression field theory to capture the nonlinear behaviour of the RC frame. The proposed method is validated against previously tested frames subjected to lateral loads, and its advantages over the conventional strut models are demonstrated through both quasi-static and dynamic analyses.
  PubDate: 2022-04-26
Seismic resilience of extra-large LNG tank built on liquefiable soil
deposit capturing soil-pile-structure interaction
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  Abstract: Abstract Assessment of seismic resilience of critical infrastructure such as liquefied natural gas (LNG) storage tanks, is essential to ensure availability and security of services during and after occurrence of large earthquakes. In many projects, it is preferred to build energy storage facilities in coastal areas for the ease of sea transportation, where weak soils such as soft clay and loose sand with liquefaction potential may be present. In this study, three-dimensional finite element model is implemented to examine the seismic response of a 160,000 m3 full containment LNG tank supported by 289 reinforced concrete piles constructed on liquefiable soil overlaying the soft clay deposit. The seismic soil-structure interaction analysis was conducted through direct method in the time domain subjected to the 1999 Chi-Chi and the 1968 Hachinohe earthquakes, scaled to Safe Shutdown Earthquake hazard level for design of LNG tanks. The analyses considered different thicknesses of the liquified soil deposit varying from zero (no liquefaction) to 15 m measured from the ground surface. The key design parameters inspected for the LNG tank include the acceleration profile for both inner and outer tanks, the axial, hoop and shear forces as well as the von Mises stresses in the inner tank wall containing the LNG, in addition to the pile response in terms of lateral displacements, shear forces and bending moments. The results show that the seismic forces generated in the superstructure decreased with increasing the liquefied soil depth. In particular, the von Mises stresses in the inner steel tank exceeded the yield stress for non-liquefied soil deposit, and the elastic–plastic buckling was initiated in the upper section of the tank where plastic deformations were detected as a result of excessive von Mises stresses. However, when soil liquefaction occurred, although von Mises stresses in the inner tank shell remained below the yield limit, localised stress concentrations were observed in the lower section of the tank near the base, increasing the risk of the elephant foot buckling. The lateral displacements, shear forces and bending moments in the piles increased with increasing depth of the liquefied soil. Indeed, increasing the pile lateral displacement amplified the bending moment at the pile head, thus resulting in increases in the pile bending moments especially when the liquefied soil depth exceeded one third of the entire soil deposit. In particular, the bending moment at the pile head exceeded the yield moment capacity of the pile and subsequent plastic hinges were formed. Moreover, when the thickness of the liquefied soil was more than half of the entire soil depth, the mobilised bending moments in the piles exceed the ultimate moment capacity of the pile and thus total failure of the piles were observed. In addition, in the absence of liquefied soil layer, the inertial interaction had a dominant impact on the pile response in this study. However, with increasing the thickness of the liquefied layer, further loads were developed in the piles due to amplified kinematic interaction, while the inertial interaction-induced loads decreased.
  PubDate: 2022-04-23
Simplified numerical approach for the structural analysis of monumental
historical aggregates: the case study of Certosa di Calci
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  Abstract: Abstract Monumental historical buildings are worldwide recognized as a fundamental component of the World Cultural Heritage to be preserved for future generations. Their structural performance analysis needs to face challenging issues such as the usually limited initial knowledge, the generally large dimensions, and the great structural complexity coming from overlapped construction phases over centuries. The structural behavior of historical constructions, therefore, differs from ordinary buildings, since resulting from the interaction of different parts, recognizable as ‘structural units’. A methodology accounting for all the peculiarities of monumental masonry buildings is proposed with reference to the specific case study of La Certosa di Calci (Italy). The monumental cluster is ideally decomposed into its structural units based on a preliminary knowledge phase, allowing to perform detailed structural analyses only on selected areas without resorting to a cumbersome and time demanding global model. The aggregate-effect influence over the structural behavior of a single unit is investigated by means of nonlinear analysis performed on different configurations. Achieved results are accurately analyzed, finally proposing a simplified model where one structural unit is represented through a FEM model and the interaction effects due to the adjacent portions are simulated through a calibrated spring system.
  PubDate: 2022-04-22
Experimental seismic performance of a reduce-scale stone masonry loess
cave with traditional buildings
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  Abstract: Abstract The seismic behavior of the independent type of a stone masonry loess cave (SMLC) is examined. A tri-directional shake table test was employed on 1:4 reduced-scale specimen of SMLC. The specimen represented a typical traditional dwelling of the loess region in China, consisting of unreinforced masonry walls and inner loess, without any seismic treatment. The dynamic parameters directly measured by the test include the acceleration response, displacement response of each key position of the stone masonry loess cave, and the detailed record of the damage form of the structure under each loading. The analysis results indicated that the simplified model design method not only satisfied the main similarity relationship of the reduced-scale structure shaking table test, but also achieved excellent test results. Through the calculation results to determine the torsion angle of the node and the deformation between the layers, corresponding strengthening measures could be proposed for the life extension protection of this traditional building. Finally, according to the analysis of the test results, the damage state and damage level of the prototype of the SMLC is established.
  PubDate: 2022-04-19
Damage tracking and evaluation of RC columns with structural performances
by using seismic monitoring data
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  Abstract: Abstract A methodology of data-driven damage state quantification with a probability estimation for structural hysteresis of RC columns is presented in this paper. The knowledge learned from a large-volume structural behavior database is fully considered for developing monitoring-oriented damage indicators, with the established relationship between data-driven damage prediction and physics-based damage state evaluation. In the present study, a database of the hysteresis behavior of 1015 RC columns with different design parameters is first generated by adopting OpenSees, with categorization according to the primary design parameter of the axial load ratio. Four limit states of seismic performance with the corresponding values of the proposed damage index are calculated to generate an informative mapping between critical damage states and damage index values. By fitting probabilistic models on the grouped data of damage indices, the exceeding probabilities of damage states corresponding to damage index values can be obtained. Illustrative examples of full-scale RC columns with cyclic loading and shaking table tests are adopted to illustrate the proposed performance-based damage evaluation process.
  PubDate: 2022-04-19
Seismic response behavior of deep flexible underground structures in
sand-insights from an experimental–numerical investigation
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  Abstract: Abstract The evaluation of soil-structure response behavior and the development of soil pressures under dynamic loading is critical for the design of closely spaced underground structures. 3D effects, kinematic soil-structure interaction (SSI), and elastic–plastic soil behavior are common limitations to current analytical approaches and 2D numerical models. Results from large-scale shake table tests conducted at E-Defense are used to create and calibrate a 3D FEM model in Abaqus. The complex SSI behavior was validated in terms of depth-dependent soil accelerations and magnitude and distribution of seismic soil pressures along the vertical shaft walls. Parametric studies were executed to assess the influence of soil friction angle, soil cohesion, as well as structural rigidity on the development of seismic soil pressures and wall deformations. Results suggested the soil cohesion to be instrumental on the wall-soil-interaction, and superior in its influence compared to friction angle. The paper presents valuable details and lessons learned from the extensive 3D modeling exercise and provides guidance for numerical replication of shake table experiments, including the simulation of laminar shear rings, contact elements, soil-ring friction, as well as membrane and boundary effects.
  PubDate: 2022-04-13
The 2021 seismic hazard model for Slovenia (SHMS21): overview and results
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  Abstract: Abstract Slovenia is an earthquake-prone country with a moderate seismic hazard, characterized by relatively long recurrence intervals for strong earthquakes. With newly compiled data and revised info on active faults of the region, we are now able to supplement and enhance the probabilistic seismic hazard assessment, which was previously based mainly on the seismic catalog. The core of the seismic hazard model is the seismogenic source model combining various seismogenic representations i.e. area and gridded sources, and active faults. The ground motion model is characterized by a backbone model with regionalized parameters, which was also used to update the European seismic hazard model. We considered epistemic uncertainty in the most influential input parameters, implemented in a logic tree with 1377 branches. Considering the existing and forthcoming requests of the seismic design standard—Eurocode 8, we have developed the peak ground acceleration map of Slovenia and spectral acceleration maps for ten spectral periods, as well as seismic hazard curves and spectra for selected locations. The highest peak ground acceleration values (0.325 g) are at the western border of Slovenia with Italy. Other high-hazard areas extend across the Dinarides, in southeast Slovenia, and around the capital Ljubljana.
  PubDate: 2022-04-12
Vulnerability prediction model of typical structures considering empirical
seismic damage observation data
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  Abstract: Abstract To deeply explore the seismic vulnerability characteristics of typical structures and obtain the differences in the seismic capacity of multiple structural categories in actual earthquakes, combined with mathematical statistics and probabilistic damage model analysis methods, the bulk of collection and statistics were made on the structural seismic damage observation data (98,051.8122 × 104 m2 and 995,269 buildings) of 213 destructive earthquakes in China from 1975 to 2013. Seismic damage sample databases of wooden roof truss structures, adobe and timber structures, brick wood structures, masonry structures, RC structures, and bottom frame seismic wall masonry structure were established. A seismic damage investigation and analysis were conducted. All samples’ vulnerability grades were evaluated using the latest version of the Chinese seismic intensity scale (CSIS-20). The actual damage vulnerability probability matrix and surface model of structures in multiple intensity regions based on the investigated area and quantity parameters were established. A nonlinear regression prediction model analysis method was proposed. A typical structural vulnerability prediction model considering the failure ratio and exceedance probability in the multi-intensity region was established and verified by the earthquake damage database. In addition, a vulnerability matrix prediction model considering updating the mean vulnerability index parameter was proposed, and a comparison model of the vulnerability prediction matrix of typical regional structures was developed.
  PubDate: 2022-04-10
Usage of Tyre Derived Aggregates as backfill around buried pipelines
crossing strike-slip faults; model tests
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  Abstract: Abstract Buried pipelines crossing active faults are exposed to excessive soil forces under fault movements due to large relative movement between pipes and the soil surrounding them. As a result, extreme longitudinal strains develop within pipelines under large fault movements and this leads to pipeline failures. Several seismic mitigation techniques were proposed to improve the performance of buried pipelines crossing active faults. In this study, the potential of using Tyre Derived Aggregates (TDA) as a backfill material for mitigating the effects of strike-slip faulting are investigated through physical model tests. First, the details of the physical model test setup and model configuration are presented. Then a comparative study is carried out to study the effect of TDA content in the backfill and trench configurations on TDA mitigation. Model tests revealed that using a sloped trench with 100% TDA content in the backfill can decrease peak axial pipe strains up to 62% and peak bending strains up to 19%. It is observed that enlarging the trench and using an inclined trench improve the performance of the TDA mitigation technique.
  PubDate: 2022-04-09
Selection and spectral matching of recorded ground motions for seismic
fragility analyses
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  Abstract: Abstract Ground motion selection is one of the most important phases in the derivation of fragility curves through non-linear dynamic analyses. In this context, an easy-to-use software, namely S&M—Select & Match, has been adopted for the selection and spectral matching of recorded ground motions approaching a target response spectrum in a broad period range. In this paper, after a brief description of the key features of the S&M tool, two sets of 125 accelerograms, separately for stiff (i.e. site classes A and B according to the Italian code) and soft soil (i.e. site classes C and D) conditions, have been selected on the basis of the elastic design spectra of the Italian seismic code defined for different return periods. The selected ground motions have been analysed and used for non-linear dynamic analysis of a case study representative of a common Italian RC building type designed only to gravity loads. Results have been analysed in order to check the capability of the considered signals to adequately cover all the damage levels generally adopted in seismic risk analyses, as well as the effects on seismic response due to the selection criteria permitted by the proposed tool.
  PubDate: 2022-04-08