Earthquake-induced Ground Failure Research Articles

Unmanned Aerial Photography Futures to explore surface deformations and their visualization on the geoportal “ActiveTectonics”

On the example of the Rita River delta and alluvial fan of the Shartlai River located on the northwestern coast of Lake Baikal, we show the possibilities of ultra-detailed aerial photography, which allows tracing surface discontinuities with displacements from a few centimeters. The software package "Agisoft Metashape" was applied for analyzing the multi-temporal digital elevation models with the same spatial resolution of 1,67 cm/pixel to fix possible changes in the earth's surface over the year for the local area of earthquake-induced ground failures at Cape Rytyi. It has been established that most of this part has sunk by an average of 5–10 cm per year, and in the axial parts of the faults, subsidence has reached 33 cm. The greatest accumulation of sediments (up to 40 cm thick in some places) occurred on the shore, which is mainly due to the geological activity of the waves of Lake Baikal. Based on the relationship between ruptures and alluvial fans of different ages, we concluded at least two rupturing paleoearthquakes at Cape Shartlai. On the author's geoportal "ActiveTectonics", we uploaded some materials of unmanned aerial photography and geological objects in the form of orthophotomaps, digital elevation models and 360° panoramas that significantly expands the possibilities of data perception which are the basis for scientific results and conclusions.

The correction factor of Monterey No. 0/30 sample with fines content liquefaction resistance between cyclic triaxial and cyclic hollow cylinder tests

Soil liquefaction is one of the most detrimental forms of earthquake-induced ground failure that can result in catastrophic damage to engineering structures. For the seismic safety evaluation of foundations and high-rise structures, it is the most critical way to assess liquefaction resistance. In this paper, an array number of isotropically consolidated undrained cyclic triaxial tests (CTT) and cyclic hollow cylinder tests (CHCT) have been performed to evaluate soil liquefaction resistance. Thirty-seven isotopically consolidated undrained cyclic triaxial tests and thirty-seven cyclic hollow cylinder tests were run on the uniform medium Monterey No. 0/30 sand and it is with four different percentages of fine content. By using cyclic triaxial and cyclic hollow cylinder tests for evaluating liquefaction resistance, it helps us better understand the relationship between two types of tests on uniform clean Monterey No. 0/30 sand and soil sample with five different percentages of fines content. Four different relative densities of 30%, 45%, 50%, and 60%, two confining pressure of 103 kpa and 207 kpa, and five cyclic stress ratios (0.15, 0.2, 0.25, 0.3, and 0.4) have been used for a series of cyclic triaxial tests and cyclic hollow cylinder tests. At the same relative densities of 30% and 60%, the correction factor between CTT and CHCT evaluated ranged from 0.46 to 0.63 on the uniform clean Monterey No. 0/30 sand. Statistical analyses were performed to formulate functional relationships for predicting the correction factor of soil liquefaction resistance between CTT and CHCT tests.

Developments in Seismic Vulnerability Assessment of Tunnels and Underground Structures

Underground structures are being constructed at an increasing rate in seismic prone areas, to facilitate the expanding needs of societies. Considering the vital role of this infrastructure in densely populated urban areas and interurban transportation networks, as well as the significant losses associated with potential seismically induced damage, its assessment against seismic hazard is of great importance for stakeholders, operators, and governmental bodies. This paper presents a state-of-the-art review of current developments in the assessment of seismic vulnerability of tunnels and underground structures. Methods for the development of fragility functions for the assessment of bored tunnels in rock or alluvial, and cut and cover tunnels and subways in alluvial, against ground seismic shaking and earthquake-induced ground failures are presented. Emphasis is placed on the estimation of the capacity of the examined structures, the selection of appropriate intensity measures to express seismic intensity, the development of rational probabilistic seismic demand models and the estimation of epistemic and aleatoric uncertainties, related to the seismic fragility of underground structures. Through the discussion, acknowledged gaps in the relevant literature are highlighted.

Automatic detection of earthquake-induced ground failure effects through Faster R-CNN deep learning-based object detection using satellite images

The seismically induced ground failure is defined as any earthquake-generated process that leads to deformations within a soil medium, which in turn results in permanent horizontal or vertical displacements of the ground surface. As a result, relative movements occur on the ground and structures affected by these movements and thus they may be damaged. Determining earthquake-induced ground failure areas is important to carry out damage assessment studies more quickly and reliably and to prevent more destructive damages. Large earthquake-induced ground failure areas or limited access to the areas due to earthquake causes costly and unsafe fieldwork. Using satellite photographs, earthquake-induced ground failure areas can be easily and reliably detected and the fieldwork can be planned quickly. This study aimed at determining the postearthquake-induced ground failure areas and buildings or structures partially ruined (damaged) by using a deep learning-based object detection method, using Google Earth satellite images after an earthquake. The data set obtained after the earthquake occurred in the 2018 Palu region of Indonesia was used. This data set is divided into two parts for training and test areas. A descriptive approach is considered for detecting the earthquake-induced ground failure areas and damaged structures from collected images from Google Earth software using satellite photographs, using a pretrained Faster R-CNN. To demonstrate the effectiveness of the proposed method, the data set was first created with Google Earth Pro software and it was generated with 392 images for the earthquake-induced ground failure area and 223 images for the damaged area with a resolution of 1024 × 600 pixels. The analyses were carried out by taking into account different image scales. As a result of the analyses, it was concluded that the earthquake-induced ground failure effects (liquefied soil) and damaged structures can be detected to a large extent by using object detection-based deep learning methods.

2-2)防災面からみた地震と地盤災害(第2部 地震防災と地質学,C.地震と地盤災害-兵庫県南部地震の教訓-)

2-2)防災面からみた地震と地盤災害(第2部 地震防災と地質学,C.地震と地盤災害-兵庫県南部地震の教訓-)

Evaluation of Seismic Protection Methods for Buried Fuel Pipelines Subjected to Fault Rupture

Buried steel fuel pipelines are critical lifelines for the society and the economy, but are very vulnerable to earthquake-induced ground failure. Traversing seismic areas inevitably results to several pipe – fault crossings. Fault rupture forces a buried pipeline to undergo deformations that could be substantial and heavily endanger its integrity. Due to the grave consequences of a potential pipe failure, mitigating measures are commonly applied at pipe – fault crossings to reduce the effects of a potential fault activation. In this paper, a comparative review of several measures that are used in practice or have been proposed in the technical literature is presented. Numerical analyses are then carried out to compare the effectiveness of commonly used measures and to extract conclusions regarding their applicability. Results indicate that the most efficient among the evaluated measures are pipe placement within culverts and use of flexible joints. Trench backfilling with pumice is a moderately effective measure in terms of pipe protection, while steel grade upgrade, wall thickness increase and pipe wrapping with geotextile are found to be insufficient protection methods.

Surface Rupture and Geotechnical Features of The July 2, 2013 Tanah Gayo Earthquake

DOI:10.17014/ijog.3.2.95-105An assessment of surface rupture and collateral ground failures can help to evaluate the impact of future earthquakes. This paper presents the results of a field survey conducted to map the surface rupture and geotechnical phenomena associated with the ground shaking during the July 2, 2013 earthquakes in Tanah Gayo Highland. The objectives of this survey are to document and to characterize the surface ruptures as well as to identify types of earthquake-induced ground failures. Results of the survey identified four best sites of possible surface rupture. Two locations are obvious surface ruptures that can be traced on primary topographic feature of the active fault segment from the north to the south, crossing Pantan Terong Hill. The fault segment has a total mapped length of 19 km, with WNW trending zone and a dextral rupture offset. The ground shaking also resulted in landslides and liquefaction in areas underlain by very fine-grained tuffaceous sands. Based on the field survey, it can be concluded that the newly defined active fault segment, the Pantan Terong segment, is likely the segment that ruptured at the July 2, 2013 Tanah Gayo earthquake. Due to the soil types and unstable rocky slopes in the hilly Central Aceh region, large-scale landslides are primary risks during an earthquake event in this region.

Pedestrian flow-path modeling to support tsunami evacuation and disaster relief planning in the U.S. Pacific Northwest

Successful evacuations are critical to saving lives from future tsunamis. Pedestrian-evacuation modeling related to tsunami hazards primarily has focused on identifying areas and the number of people in these areas where successful evacuations are unlikely. Less attention has been paid to identifying evacuation pathways and population demand at assembly areas for at-risk individuals that may have sufficient time to evacuate. We use the neighboring coastal communities of Hoquiam, Aberdeen, and Cosmopolis (Washington, USA) and the local tsunami threat posed by Cascadia subduction zone earthquakes as a case study to explore the use of geospatial, least-cost-distance evacuation modeling for supporting evacuation outreach, response, and relief planning. We demonstrate an approach that uses geospatial evacuation modeling to (a) map the minimum pedestrian travel speeds to safety, the most efficient paths, and collective evacuation basins, (b) estimate the total number and demographic description of evacuees at predetermined assembly areas, and (c) determine which paths may be compromised due to earthquake-induced ground failure. Results suggest a wide range in the magnitude and type of evacuees at predetermined assembly areas and highlight parts of the communities with no readily accessible assembly area. Earthquake-induced ground failures could obstruct access to some assembly areas, cause evacuees to reroute to get to other assembly areas, and isolate some evacuees from relief personnel. Evacuation-modeling methods and results discussed here have implications and application to tsunami-evacuation outreach, training, response procedures, mitigation, and long-term land use planning to increase community resilience.

Earthquake-induced ground failures in Italy from a reviewed database

Abstract. A database (Italian acronym CEDIT) of earthquake-induced ground failures in Italy is presented, and the related content is analysed. The catalogue collects data regarding landslides, liquefaction, ground cracks, surface faulting and ground changes triggered by earthquakes of Mercalli epicentral intensity 8 or greater that occurred in the last millennium in Italy. As of January 2013, the CEDIT database has been available online for public use (http://www.ceri.uniroma1.it/cn/gis.jsp ) and is presently hosted by the website of the Research Centre for Geological Risks (CERI) of the Sapienza University of Rome. Summary statistics of the database content indicate that 14% of the Italian municipalities have experienced at least one earthquake-induced ground failure and that landslides are the most common ground effects (approximately 45%), followed by ground cracks (32%) and liquefaction (18%). The relationships between ground effects and earthquake parameters such as seismic source energy (earthquake magnitude and epicentral intensity), local conditions (site intensity) and source-to-site distances are also analysed. The analysis indicates that liquefaction, surface faulting and ground changes are much more dependent on the earthquake source energy (i.e. magnitude) than landslides and ground cracks. In contrast, the latter effects are triggered at lower site intensities and greater epicentral distances than the other environmental effects.

Rock-falls and liquefaction related phenomena triggered by the June 8, 2008, Mw=6.4 earthquake in NW Peloponnesus, Greece

<p>A strong earthquake (M<sub>w</sub>=6.4) occurred in NW Peloponnesus, Greece, on June 8, 2008. The focal mechanism shows a transcurrent kinematics, and based on aftershocks distribution the causative fault is a dextral strike-slip NNE-SSW trending structure. The shock generated severe secondary environmental effects like rock-falls and liquefaction phenomena inducing structural damages and ground failures mainly along the fault strike. Evidence of liquefaction was observed in the area of Kato Achaia and Roupakia villages, while rock-falls were triggered mainly close to the epicentre at the foothills of the Skolis Mountain. Based on a quantitative methodological approach, the ground deformation and failures generated by the event have been investigated. In particular, based on an immediate post-event survey, we mapped in detail the distribution of the earthquake-induced ground failures, defining the areas prone to liquefaction and their associated potential. Moreover, a rock-fall hazard zonation in the area of Skolis Mountain has been developed based on the shadow angle approach, confirming the validity of the safety run-out distance models.</p>

Field evidence of seismites in Quaternary deposits of the Jijel (Eastern Algeria) coastal region

Jijel has been hit by a strong earthquake in 1856 that triggered a destructive tsunami. Field geological investigations show that the marine terrace deposits (Tyrrhenian or likely Eutyrrhenian) exhibit several types of soft sediment deformation features including sismoslumps, thixotropic bowls, thixotropic wedges, and diapir-like structures. In addition, paleo-liquefaction features represented by neptunian and injection dikes have been observed in the sand dune deposits (Aterian or Wurm). Furthermore, typical paleo-earthquake-induced ground failures including lateral spreading, paleo-landslides, and sand volcanoes have been observed in recent, likely, Holocene deposits. Such features, remarkably comparable to present-day earthquake-induced ground failures showing clearly repetitive occurrence of past events may constitute a precious material for future paleo-seismic investigation. The various features have been interpreted herein as seismites associated to strong earthquakes produced likely by the potentially active faults previously identified in the area.

Archeoseismic study of damage in Roman and Medieval structures in the center of Cologne, Germany

The causes of damage observed in archeological records or preserved monuments are often difficult to be determined unequivocally, particularly when the possibility of secondary earthquake damage exists. Such secondary damage has been previously proposed for the Roman Praetorium, the governor’s palace in the center of Cologne. Ongoing excavations since 2007 revealed additional damage. The existing ground that has been uncovered and documented extends the affected area to 175 × 180 m. We present a comprehensive virtual model of the excavation area based on 200 3D laserscans together with a systematic analysis of the damage patterns and an improved model of the terrain during Roman/Medieval times including geotechnical parameters of the subsurface. Five locations with different damage patterns, including a Roman sewer, the octagonal central part of the Praetorium, a section with strongly inclined massive walls, a 13 m deep deformed well, a collapsed hypocaust, and damages in the Medieval mikveh are analyzed in detail. We use site-specific synthetic strong ground motion seismograms to test the possibility of earthquake-induced ground failures as a cause for the observed damage. This subsurface model is also used to test the possibility of hydraulically-induced damages by seepage and erosion of fine-grained material from stray sand. Heavy rainstorms can induce a direct stream of surface water through the fine sand layers to the ground water table. Simulated ground motion for assumed worst-case earthquake scenarios do not provoke slope instability at the level necessary to explain the structural damages.

Liquefaction identification using class-based sensor independent approach based on single pixel classification after 2001 Bhuj, India earthquake

A strong earthquake with magnitude 7.7 that shook the Indian Province of Gujarat on the morning of January 26, 2001 caused wide spread destruction and casualties. Earthquakeinduced ground failures, including liquefaction and lateral spreading, were observed in many areas. Optical remote sensing offers an excellent opportunity to understand the post-earthquake effects both qualitatively and quantitatively. The impact of using conventional indices from Landsat-7 temporal images for the liquefaction is empirically investigated and compared with class-based sensor independent (CBSI) indices, while applying possibilistic fuzzy classification as a soft computing approach via supervised classification. Five spectral indices, namely simple ratio (SR), normalized difference vegetation index (NDVI), transformed normalized difference vegetation index (TNDVI), soil-adjusted vegetation index (SAVI), and modified normalized difference water index (MNDWI) are investigated to identify liquefaction using temporal multi-spectral images. A soft-computing based fuzzy algorithm, which is independent of statistical distribution data assumption, is used to extract a single land cover class from remote sensing multi-spectral images. The result indicates that appropriately used indices can incorporate temporal variations, while extracting liquefaction with soft computing techniques for coarser spatial resolution with temporal remote sensing data. It is found that CBSI-NDVI with temporal data was good for extraction liquefaction while CBSI-TNDVI with temporal data was good for extraction water bodies.

Geotechnical aspects of the 2007 Niigataken Chuetsu-Oki, Japan earthquake

On 16 July 2007, an earthquake of magnitude 6.8 occurred with an epicentre off the west coast of Niigata Prefecture (Japan), causing widespread damage to buildings and other types of civil engineering structures due to ground shaking and earthquake-induced ground failures. Landsliding and soil liquefaction occurred extensively in various parts of the affected region. This paper presents the preliminary results of the post-earthquake damage investigation conducted at the affected areas after the earthquake, with emphasis on the seismic-induced ground failures and their effects on the built environment.

The influence of hazard models on GIS-based regional risk assessments and mitigation policies

Geographic information systems (GIS) are important tools for understanding and communicating the spatial distribution of risks associated with natural hazards in regional economies. We present a GIS-based decision support system (DSS) for assessing community vulnerability to natural hazards and evaluating potential mitigation policy outcomes. The Land Use Portfolio Modeler (LUPM) integrates earth science and socioeconomic information to predict the economic impacts of loss-reduction strategies. However, the potential use of such systems in decision making may be limited when multiple but conflicting interpretations of the hazard are available. To explore this problem, we conduct a policy comparison using the LUPM to test the sensitivity of three available assessments of earthquake-induced lateral-spread ground failure susceptibility in a coastal California community. We find that the uncertainty regarding the interpretation of the science inputs can influence the development and implementation of natural hazard management policies.

Earthquake losses due to ground failure

Ground shaking is widely considered to be the primary cause of damage to structures, loss of life and injuries due to earthquakes. Nonetheless, there are numerous examples of earthquakes where the losses due to earthquake-induced ground failure have been significant. Whereas ground shaking causes structural and non-structural damage, with associated loss of function and income, ground failure is less likely to cause spectacular structural collapses, but is frequently the cause of major disruptions, particularly to lifelines, which can lead to prolonged loss of function and income, even for undamaged areas. Those involved in earthquake loss modelling are currently presented with three choices with respect to the incorporation of ground failure: they can choose to ignore it, assuming that any estimation of losses caused by shaking would effectively subsume the impact of these secondary hazards; they can include ground failure in a simple manner, using published approaches based upon qualitative data and a large degree of judgement; or, they can opt for a detailed site- or region-specific assessment of damage due to ground failure, with the associated time and expense. This paper presents a summary of the principal features of earthquake losses incurred in damaging earthquakes over the last 15 years. Survey data are impartially analysed, considering both ground failure and ground shaking as sources of damage, and their relative contribution to overall damage in each section of the regional infrastructure is presented. There are many other variables influencing these contributions, including the size of the earthquake, the economic status of the affected region, local geology and terrain and the building stock, which have been considered. The findings of the study are discussed from the point of view of loss modelling and which components of a model should merit the most time and resource allocation. The general assumption that ground shaking is the principal cause of damage and loss is strongly supported by the study. However, there are a number of scenarios identified where the failure to appropriately include the effects of ground failure would lead to unrealistic loss projections. Such scenarios include the assessment of building losses in small zones rather than on a regional basis, and the incorporation of lifeline damage or disruption and indirect losses into a model.

Geotechnical Aspects of the January 13, 2001 El Salvador Earthquake

An earthquake of magnitude 7.6 occurred in the south-east coast of El Salvador on January 13, 2001, causing widespread damage to buildings and several kinds of civil engineering structures due to ground shaking and earthquake-induced ground failures, including several large-scale landslides. This paper discusses the results of the damage investigation conducted in the area after the earthquake, with emphasis on the general features of the earthquake and its effects on the ground damage, specifically the landsliding which occurred in natural slopes and the liquefaction of soil deposits. The occurrence of liquefaction in the alluvial plain exhibited several characteristics in common with those observed in other areas of similar condition. On the other hand, the main cause of slope failures in volcanic deposits was not clearly identified, and several possible sources of slope instability were pointed out.

Rapid assessment procedure to demarcate areas susceptible to earthquake-induced ground failures for environment management - a case study from parts of northeast India

Ground failures, such as landslide and the liquefaction of soil induced by earthquake and/or rainfall, not only pose a threat to human settlements but also degrade the environment. In order to be as prepared as possible, prior knowledge of the spatial distribution of areas vulnerable to these natural hazards and the critical locations for different degrees of risk is required. Information on the land cover, surface drainage, morphology, surface material, rock type, geological structure, lineament, rainfall and earthquake was used in developing a procedure to evaluate regions of potential ground failure. A case study from northeast India is presented to illustrate its value.

Earthquake-induced ground failures in Italy

The National Catalog of Ground Failures Induced by Strong Earthquakes in Italy (CEDIT), is described. The catalog holds data on ground failures triggered by the earthquakes that occurred in Italy in the last millennium and which had a nominal epicentral intensity equal to or greater than VIII in the Mercalli–Cancani–Sieberg (MCS) intensity scale. The ground effects reported in the catalog are the following: landslides, fractures, liquefaction, surface faulting, and topographic changes of the ground level (subsidence, settlements, tilting, and so on). Each effect is described in terms of seismological parameters of the triggering earthquake, site coordinates and administrative code, lithology and kinematic type of the ground failure. The catalog represents a tool to assess the susceptibility of geologic materials to ground shaking, and to validate predictive models of seismically induced ground displacements (scenarios of earthquake-induced geologic risks). In the context of this study, a simple statistical analysis of the database yielded useful relations between the parameters of the triggering earthquakes and the related effects.

Provisional seismic zoning for ground failures in portions of Los Angeles and Ventura counties following the 17 January 1994 Northridge earthquake

Abstract Provisional seismic hazard zones for earthquake-induced ground failures have been delineated for portions of the three-county area most affected by the Northridge earthquake using a simplified hazard assessment methodology. The procedure integrates surface geology, topography, and groundwater information using GIS technology. While not a replacement for “official” seismic hazard zones, which are based on a more detailed and comprehensive analysis of hazard, these provisional zones will assist in the immediate and cost-effective distribution of postearthquake hazard mitigation funds.