Damage Probability Assessment of Hospital Buildings in Yogyakarta, Indonesia as Essential Facility due to an Earthquake Scenario

Indonesia is a country located in an earthquake-prone region, and is characterized by significantly increased peak ground acceleration value. The seismic hazard map of Indonesia stated in SNI 1726-2012 and the current statistics published by PUSGEN in 2017 emphasized on the significance of assessing building damage probabilities, especially for essential structures in Yogyakarta. However, immediate action is required to handle response and recovery operations during and after a disaster. The aim of this study, therefore, is to ascertain the vulnerability and damage probability of hospital buildings in Yogyakarta by employing the 2006 earthquake scenario, where reports showed the destruction of over 156,000 houses and other structures. Furthermore, a Hazard-US (HAZUS) method was used for structural analysis, while a ground motion prediction equation was adopted to produce the building response spectra, following the characteristics of the earthquake incidence. The vital step in this assessment involves building type classification and identification of seismic design levels. However, the damage tendency of buildings is determined using the peak building response, which ensures the generation of capacity curves. The most significant findings on building damage probability value were less than 15% in each damage state (slight, moderate, extensive, complete). In addition, the optimum value was achieved at the minimum level of damage (minor), while the least values were recorded at the highest damage level (complete).

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Case Study of a Heavily Damaged Building during the 2016 MW 7.8 Ecuador Earthquake: Directionality Effects in Seismic Actions and Damage Assessment

Geosciences ◽

10.3390/geosciences11020074 ◽

2021 ◽

Vol 11 (2) ◽

pp. 74

Author(s):

Luis A. Pinzón ◽

Luis G. Pujades ◽

Irving Medranda ◽

Rodrigo E. Alva

Keyword(s):

Damage Assessment ◽

Strong Motion ◽

Response Spectra ◽

Seismic Action ◽

Damage State ◽

Ground Acceleration ◽

Intensity Measures ◽

Capacity Curves ◽

Building Orientation

In this work, the directionality effects during the MW 7.8 earthquake, which occurred in Muisne (Ecuador) on 16 April 2016, were analyzed under two perspectives. The first one deals with the influence of these effects on seismic intensity measures (IMs), while the second refers to the assessment of the expected damage of a specific building located in Manta city, Ecuador, as a function of its azimuthal orientation. The records of strong motion in 21 accelerometric stations were used to analyze directionality in seismic actions. At the closest station to the epicenter (RRup = 20 km), the peak ground acceleration was 1380 cm/s2 (EW component of the APED station). A detailed study of the response spectra ratifies the importance of directionality and confirms the need to consider these effects in seismic hazard studies. Differences between IMs values that consider the directionality and those obtained from the as-recorded accelerograms are significant and they agree with studies carried out in other regions. Concerning the variation of the expected damage with respect to the building orientation, a reinforced concrete building, which was seriously affected by the earthquake, was taken as a case study. For this analysis, the accelerograms recorded at a nearby station and detailed structural documentation were used. The ETABS software was used for the structural analysis. Modal and pushover analyses were performed, obtaining capacity curves and capacity spectra in the two main axes of the building. Two advanced methods for damage assessment were used to obtain fragility and mean damage state curves. The performance points were obtained through the linear equivalent approximation. This allows estimation and analysis of the expected mean damage state and the probability of complete damage as functions of the building orientation. Results show that the actual probability of complete damage is close to 60%. This fact is mainly due to the greater severity of the seismic action in one of the two main axes of the building. The results are in accordance with the damage produced by the earthquake in the building and confirm the need to consider the directionality effects in damage and seismic risk assessments.

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The Seismic Microzonation of the City of Catania (Italy) for the Etna Scenario Earthquake (M = 6.2) of 20 February 1818

Earthquake Spectra ◽

10.1193/1.4000013 ◽

2012 ◽

Vol 28 (2) ◽

pp. 573-594 ◽

Cited By ~ 18

Author(s):

Salvatore Grasso ◽

Michele Maugeri

Keyword(s):

Nonlinear Models ◽

Seismic Hazard Assessment ◽

Response Spectra ◽

Response Analysis ◽

Ground Response Analysis ◽

Ground Acceleration ◽

Ground Shaking ◽

Earthquake Scenario ◽

Lower Magnitude ◽

The City

Based on the seismic history of the city of Catania (Italy), the Etna earthquake of 20 February 1818 ( IMCS = VIII–IX, MS = 6.2) has been considered as an earthquake scenario. Despite its lower magnitude, the Etna 1818 earthquake can be accounted for in the seismic hazard assessment of Catania, since it may cause heavy damage to the city. The epicenter was located along the southeastern flanks of the Etna Volcano, close to the municipal area of the city of Catania. The ground-response analysis at the surface has been obtained by one-dimensional (1-D) nonlinear models. According to the response spectra obtained through the application of the nonlinear models, the city of Catania has been divided into zones with different peak ground acceleration at the surface. A ground-shaking map for the urban area of the city of Catania was generated via GIS for the 1818 earthquake scenario.

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Developed approach to determine the seismic vulnerability of reinforced concrete structures

MATEC Web of Conferences ◽

10.1051/matecconf/201814902078 ◽

2018 ◽

Vol 149 ◽

pp. 02078

Author(s):

Serraye Mahmoud ◽

Amri Salima

Keyword(s):

Seismic Vulnerability ◽

Fragility Curves ◽

Response Spectrum ◽

Response Spectra ◽

Seismic Intensity ◽

Point Of View ◽

Damage State ◽

Capacity Curves ◽

Performance Point ◽

Materials Used

Several evaluation methods of the seismic vulnerability have been developed around the world. Which are very use ful from humanitarian and socioeconomic point of view. Generally these methods use knowledge obtained from previous earthquakes and they are basing on seismic intensity scales and on buildings direct observation. But the macroseismic intensity expresses the consequences of the seism, and not its physical characteristics of the structures. Contrary to this type of methods, an approach based on a nonlinear analysis (Push-Over method) is proposed in this work. It consists in modeling the excitation of the earthquake by a response spectrum and building's behavior by capacity curves. These capacity curves are obtained from numerical modeling performed by Opensees software. The superposition of the two curves, response spectra and capacity curve, makes it possible to determine the performance point and consequently to deduce the state of expected damage. To estimate the probability of damage of a building at a given level of solicitation (defined by Sd), we excites a group of buildings characterized by different parameters related to the geometry of the building and those are related to the materials used (concrete, steel) by seismic solicitation (Response spectrum - RPA 99). The performance point for each building is determined by a procedure defined in FEMA 440. We classifies the buildings according to the position of performance point on their curve which defines a damage state of ds (Mild, Moderate, Important or Ruin) according to the damage levels of Risk-UE. A statistical analysis is then made for each class to build the fragility curves.

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Typological Damage Fragility Curves for Unreinforced Masonry Buildings affected by the 2009 L'Aquila, Italy Earthquake

The Open Civil Engineering Journal ◽

10.2174/1874149502115010117 ◽

2021 ◽

Vol 15 (1) ◽

pp. 117-134

Author(s):

Maria Zucconi ◽

Rachele Ferlito ◽

Luigi Sorrentino

Keyword(s):

Peak Ground Acceleration ◽

Risk Mitigation ◽

Fragility Curves ◽

Relative Size ◽

Unreinforced Masonry ◽

Building Damage ◽

Economic Losses ◽

Structural Elements ◽

Damage State ◽

Ground Acceleration

Background: Seismic risk mitigation has become a crucial issue due to the great number of casualties and large economic losses registered after recent earthquakes. In particular, unreinforced masonry constructions built before modern seismic codes, common in Italy and in other seismic-prone areas, are characterized by great vulnerability. In order to implement mitigation policies, analytical tools are necessary to generate scenario simulations. Methods: Therefore, data collected during inspections after the 2009 L’Aquila, Italy earthquake are used to derive novel fragility functions. Compared to previous studies, data are interpreted accounting for the presence of buildings not inspected due to those being undamaged. An innovative building damage state is proposed and is based on the response of different structural elements recorded in the survey form: vertical structures, horizontal structures, stairs, roof, and partition walls. In the suggested formulation, the combination of their performance is weighted based on typical reparation techniques and on the relative size of the structural elements, estimated from a database of complete geometrical surveys developed specifically for this study. Moreover, the proposed building damage state estimates earthquake-related damage by removing the preexisting damage reported in the inspection form. Results: Lognormal fragility curves, in terms of building damage state grade as a function of typological classes and peak ground acceleration, derived maximizing their likelihood and their merits compared with previous studies are highlighted. Conclusion: The correction of the database to account for uninspected buildings delivers curves that are less “stiff” and reach the median for lower peak ground acceleration values. The building feature that influences most the fragility is the masonry quality.

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Fragility Curves Based on Data from the 2011 Tohoku-Oki Tsunami in Ishinomaki City, with Discussion of Parameters Influencing Building Damage

Earthquake Spectra ◽

10.1193/053013eqs138m ◽

2015 ◽

Vol 31 (2) ◽

pp. 841-868 ◽

Cited By ~ 25

Author(s):

Anawat Suppasri ◽

Ingrid Charvet ◽

Kentaro Imai ◽

Fumihiko Imamura

Keyword(s):

Fragility Curves ◽

Building Damage ◽

Steel Buildings ◽

Design Code ◽

Damage Level ◽

Inundation Depth ◽

Damage Probability ◽

New Findings ◽

Earthquake Resistant ◽

Vulnerability Functions

The 63,605 damaged buildings from the 2011 Tohoku-oki tsunami in Ishinomaki were used to develop 52 fragility curves using linear regression. The data comprise the damage level and the measured inundation depth for each building. In agreement with previous studies, the present results indicate that reinforced concrete and steel buildings with three stories or more perform better under tsunami loading. Performance with respect to their intended function was found to depend mainly on structural material. Moreover, based on Japan's design code for earthquake-resistant buildings, buildings constructed after 1981 do not display a better performance compared to more recent constructions. Finally, the results show that for the same inundation depth, a higher damage probability exists along a ria coast due to higher flow velocities, confirmed by numerical simulation and survivor videos. These new findings are useful for building damage assessment, town reconstruction, and comparison of vulnerability functions in future studies.

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Evaluation of floor acceleration demands from the 2017 Mexico City code seismic provisions using a continuous elastic model and records of instrumented buildings

Earthquake Spectra ◽

10.1177/8755293020974692 ◽

2020 ◽

Vol 36 (2_suppl) ◽

pp. 213-237

Author(s):

Miguel A Jaimes ◽

Adrián D García-Soto

Keyword(s):

Mexico City ◽

Seismic Design ◽

Soft Soil ◽

Response Spectra ◽

Elastic Model ◽

Ground Acceleration ◽

Nonstructural Components ◽

Floor Response Spectra ◽

Instrumented Buildings ◽

Floor Acceleration

This study presents an evaluation of floor acceleration demands for the design of rigid and flexible acceleration-sensitive nonstructural components in buildings, calculated using the most recent Mexico City seismic design provisions, released in 2017. This evaluation includes two approaches: (1) a simplified continuous elastic model and (2) using recordings from 10 instrumented buildings located in Mexico City. The study found that peak floor elastic acceleration demands imposed on rigid nonstructural components into buildings situated in Mexico City might reach values of 4.8 and 6.4 times the peak ground acceleration at rock and soft sites, respectively. The peak elastic acceleration demands imposed on flexible nonstructural components in all floors, estimated using floor response spectra, might be four times larger than the maximum acceleration of the floor at the point of support of the component for buildings located in rock and soft soil. Comparison of results from the two approaches with the current seismic design provisions revealed that the peak acceleration demands and floor response spectra computed with the current 2017 Mexico City seismic design provisions are, in general, adequate.

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From scenario-based seismic hazard to scenario-based landslide hazard: fast-forwarding to the future via statistical simulations

Stochastic Environmental Research and Risk Assessment ◽

10.1007/s00477-021-02020-1 ◽

2021 ◽

Author(s):

Luigi Lombardo ◽

Hakan Tanyas

Keyword(s):

Ground Motion ◽

Landslide Susceptibility ◽

Additive Model ◽

Landslide Hazard ◽

Northridge Earthquake ◽

Ground Acceleration ◽

Temporal Dimension ◽

Earthquake Scenario ◽

The Mean ◽

Ground Motion Scenarios

AbstractGround motion scenarios exists for most of the seismically active areas around the globe. They essentially correspond to shaking level maps at given earthquake return times which are used as reference for the likely areas under threat from future ground displacements. Being landslides in seismically actively regions closely controlled by the ground motion, one would expect that landslide susceptibility maps should change as the ground motion patterns change in space and time. However, so far, statistically-based landslide susceptibility assessments have primarily been used as time-invariant.In other words, the vast majority of the statistical models does not include the temporal effect of the main trigger in future landslide scenarios. In this work, we present an approach aimed at filling this gap, bridging current practices in the seismological community to those in the geomorphological and statistical ones. More specifically, we select an earthquake-induced landslide inventory corresponding to the 1994 Northridge earthquake and build a Bayesian Generalized Additive Model of the binomial family, featuring common morphometric and thematic covariates as well as the Peak Ground Acceleration generated by the Northridge earthquake. Once each model component has been estimated, we have run 1000 simulations for each of the 217 possible ground motion scenarios for the study area. From each batch of 1000 simulations, we have estimated the mean and 95% Credible Interval to represent the mean susceptibility pattern under a specific earthquake scenario, together with its uncertainty level. Because each earthquake scenario has a specific return time, our simulations allow to incorporate the temporal dimension into any susceptibility model, therefore driving the results toward the definition of landslide hazard. Ultimately, we also share our results in vector format – a .mif file that can be easily converted into a common shapefile –. There, we report the mean (and uncertainty) susceptibility of each 1000 simulation batch for each of the 217 scenarios.

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Broadband Strong-Motion Prediction for Future Nankai-Trough Earthquakes Using Statistical Green’s Function Method and Subsequent Building Damage Evaluation

Applied Sciences ◽

10.3390/app11157041 ◽

2021 ◽

Vol 11 (15) ◽

pp. 7041

Author(s):

Baoyintu Baoyintu ◽

Naren Mandula ◽

Hiroshi Kawase

Keyword(s):

Green’S Function ◽

Green's Function ◽

Nankai Trough ◽

Ground Motions ◽

Building Damage ◽

Steel Buildings ◽

Ground Acceleration ◽

Attenuation Relations ◽

Strong Ground Motions ◽

Strong Ground

We used the Green’s function summation method together with the randomly perturbed asperity sources to sum up broadband statistical Green’s functions of a moderate-size source and predict strong ground motions due to the expected M8.1 to 8.7 Nankai-Trough earthquakes along the southern coast of western Japan. We successfully simulated seismic intensity distributions similar to the past earthquakes and strong ground motions similar to the empirical attenuation relations of peak ground acceleration and velocity. Using these results, we predicted building damage by non-linear response analyses and find that at the regions close to the source, as well as regions with relatively thick, soft sediments such as the shoreline and alluvium valleys along the rivers, there is a possibility of severe damage regardless of the types of buildings. Moreover, the predicted damage ratios for buildings built before 1981 are much higher than those built after because of the significant code modifications in 1981. We also find that the damage ratio is highest for steel buildings, followed by wooden houses, and then reinforced concrete buildings.

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Fragility estimation for global building classes using analysis of the Cambridge earthquake damage database (CEQID)

Bulletin of Earthquake Engineering ◽

10.1007/s10518-021-01178-x ◽

2021 ◽

Author(s):

Robin Spence ◽

Sandra Martínez-Cuevas ◽

Hannah Baker

Keyword(s):

Fragility Curves ◽

Resistance Index ◽

Earthquake Damage ◽

Ground Acceleration ◽

Damage Level ◽

Ground Motion Parameter ◽

Geographical Regions ◽

Concrete Building ◽

Damage Data ◽

Regional Comparisons

AbstractThis paper describes CEQID, a database of earthquake damage and casualty data assembled since the 1980s based on post-earthquake damage surveys conducted by a range of research groups. Following 2017–2019 updates, the database contains damage data for more than five million individual buildings in over 1000 survey locations following 79 severely damaging earthquakes worldwide. The building damage data for five broadly defined masonry and reinforced concrete building classes has been assembled and a uniform set of six damage levels assigned. Using estimated peak ground acceleration (PGA) for each survey location based on USGS Shakemap data, a set of lognormal fragility curves has been developed to estimate the probability of exceedance of each damage level for each class, and separate fragility curves for each of five geographical regions are presented. A revised set of fragility curves has also been prepared in which the bias in the curve resulting from the uncertainty in the ground motion parameter has been removed. The uncertainty in the fragility curves is evaluated and discussed and the curves are compared with those from other studies. A resistance index for each class of building is developed and cross-regional comparisons using this resistance index are presented.

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Attenuation relationships of peak ground motions in the Jazan Region

Arabian Journal of Geosciences ◽

10.1007/s12517-020-06442-z ◽

2021 ◽

Vol 14 (3) ◽

Author(s):

Ali K. Abdelfattah ◽

Abdullah Al-amri ◽

Kamal Abdelrahman ◽

Muhamed Fnais ◽

Saleh Qaysi

Keyword(s):

Saudi Arabia ◽

Ground Motions ◽

Prediction Equation ◽

Peak Ground Velocity ◽

Local Magnitude ◽

Ground Acceleration ◽

Data Set ◽

Hypocentral Distance ◽

Distance Range ◽

Attenuation Relationships

AbstractIn this study, attenuation relationships are proposed to more accurately predict ground motions in the southernmost part of the Arabian Shield in the Jazan Region of Saudi Arabia. A data set composed of 72 earthquakes, with normal to strike-slip focal mechanisms over a local magnitude range of 2.0–5.1 and a distance range of 5–200 km, was used to investigate the predictive attenuation relationship of the peak ground motion as a function of the hypocentral distance and local magnitude. To obtain the space parameters of the empirical relationships, non-linear regression was performed over a hypocentral distance range of 4–200 km. The means of 638 peak ground acceleration (PGA) and peak ground velocity (PGV) values calculated from the records of the horizontal components were used to derive the predictive relationships of the earthquake ground motions. The relationships accounted for the site-correlation coefficient but not for the earthquake source implications. The derived predictive attenuation relationships for PGV and PGA are$$ {\log}_{10}(PGV)=-1.05+0.65\cdotp {M}_L-0.66\cdotp {\log}_{10}(r)-0.04\cdotp r, $$ log 10 PGV = − 1.05 + 0.65 · M L − 0.66 · log 10 r − 0.04 · r , $$ {\log}_{10}(PGA)=-1.36+0.85\cdotp {M}_L-0.85\cdotp {\log}_{10}(r)-0.005\cdotp r, $$ log 10 PGA = − 1.36 + 0.85 · M L − 0.85 · log 10 r − 0.005 · r , respectively. These new relationships were compared to the grand-motion prediction equation published for western Saudi Arabia and indicate good agreement with the only data set of observed ground motions available for an ML 4.9 earthquake that occurred in 2014 in southwestern Saudi Arabia, implying that the developed relationship can be used to generate earthquake shaking maps within a few minutes of the event based on prior information on magnitudes and hypocentral distances taking into considerations the local site characteristics.

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