Between 1950 and 1980, about half of Yokoshima Island disappeared beneath the East China Sea. The island lies about 1 km off the coast of Nagasaki and was mined for coal during the late 19th and early 20th centuries. We analyzed the geology of the island and surrounding seafloor to investigate how it became submerged. Two low-cost techniques were used to view underwater structures: a commercial drone

This study proposed an approach for the preliminary risk assessment of slopes with a potential for large volume failure. In this framework, risk is the combined consideration of landslide hazard, exposure, and vulnerability. The level of hazard is classified according to the combination of landslide susceptibility (in space) and activity (in time). The incorporation of landslide susceptibility and

Accurate and precise characterization of the subsurface stratigraphic configuration (geological model) at a given site is crucial to geotechnical engineering work. The uncertainty in the derived stratigraphic configuration can be significant, due to the strata's complexity and inherent spatial variability coupled with the limited availability of borehole data. The characterization and reduction of

The failure of landslide dams is a sudden geological disaster, and thus their formation and failure greatly threaten the security of people's lives and property. In this research, the influences of different flume gradients, dam heights, and downstream slope angles relative to the flume bed on the overtopping breaching process of noncohesive landslide dams are explored through 12 sets of model experiments

Expansive soils are widely distributed in the Danjiangkou Reservoir region (DRR), China. In recent years, with a rise in the reservoir water level (RWL), reservoir-related expansive soil landslides have gradually become a serious issue in this area. However, few studies on reservoir-related expansive landslides have been reported. Taking the Jingang landslide as a case study, a detailed analysis was

An optimal strategy for building realistic geological models must combine different geophysical techniques, each with its advantages and limitations. However, dealing with multiple geophysical datasets to derive a geological interpretation is not straightforward since geophysical parameters are not always functionally related. In this work, we propose an innovative approach consisting of using machine

Rapid-moving landslides occurred in many locations during the 2009 Padang earthquake, Sumatra. We interpreted satellite images, performed field surveys, in situ dynamic cone penetration tests, and laboratory analyses for mineralogy and physical and mechanical properties. We found that landslides occurred at 159 locations in an area of 64 km2, and these areas had pumice fall deposits overlying paleosols

The subsurface in areas affected by the Pleistocene glaciations often reveal very complex architectures and because of this, the near-surface geology is generally difficult to map and model in high detail. A number of geophysical methods focus on the uppermost part of the subsurface and are capable of mapping details, but no single method has hitherto been able to provide the detail, the data density

Bentonite is a key material for the construction of Engineered Barrier Systems (EBSs) in deep geological repositories (DGRs) for radioactive waste. Modelling of gas migration in saturated bentonite, as well as the accompanied hydromechanical (HM) processes is crucial for conducting a performance assessment for the safety of a deep geological repository (DGR). The objective of this paper is to review

Compacted block composed of 70% crushed Callovo-Oxfordian claystone and 30% MX80 bentonite has been proposed as a possible material for sealing a potential repository of radioactive waste. In this study, the compaction property of the bentonite/claystone mixtures with various bentonite fractions and water contents were first investigated to define an appropriate protocol for the fabrication of blocks

Effective thermal conductivity of clay (λeff) has essential applications in disciplines such as environmental and earth science, agriculture and engineering. Much work has been done pertaining to model thermal conductivity of clay, but no work was found to collate and synthesize these works. This study aimed to conduct an extensive review of the predictive models for thermal conductivity of clay and

Landslide susceptibility assessment is essential for regional landslide risk assessment and mitigation. Most past studies involved cell-based analysis that takes landslide incidents as geo-spatial points. Nevertheless, given that a landslide is a two-dimensional polygon on maps and a three-dimensional object in the real world, an object-wise assessment is more logical. Fusing with artificial intelligence

This paper evaluates existing geospatial liquefaction models using the observed land performance across four events of the Canterbury Earthquake Sequence and analyses the influence of region specific input variables on the models' potential to predict liquefaction manifestation. The aggregated performance for each event is assessed using receiver operating characteristic (ROC) analysis and the liquefaction

Menard pressuremeter testing has been widely used in geotechnical engineering applications for 40 years and is an important technique in determining in-situ horizontal stress distributions. In this study, Menard pressuremeter testing is combined with a “cookie-cutter” insertion technique to determine horizontal stresses for a soft-rock in an operational Australian mine. The method presents an alternative

The blow count (N) measured from the standard penetration test is widely used to predict the shear wave velocity (Vs) of soils. As the N - Vs relationships vary from one region to another, the N - Vs relationship in a region is often determined based on the regional data. When there is no region-specific data or when the region-specific data is limited, such methods can hardly be applicable. In this

Steep gradient, bad natural ecological conditions, and lack of nutrient conditions necessary for vegetation growth led a large number of rock-slopes exposed and serious consequences felt with respect to ecological environment. The chemical material was used to improve the mechanical properties, erosion resistance and integrity of clayey soil, which could be the main materials in the artificial reconstruction

The 1999 Chi-Chi, Taiwan, earthquake (Mw 7.6) caused damage to 49 tunnels within 60 km of the epicenter, including the collapse of three mountain tunnels, ending the traditional perception that tunnels, and especially mountain tunnels, were earthquake-resistant. A series of studies that involved seismic damage investigation, physical model and numerical simulation experiments, numerical analyses and

The dip-slope Chiu-fen-erh-shan landslide, estimated to have a volume of 36 × 106 m3, was triggered by the Mw 7.6 Chi-Chi earthquake. The debris covered an area of 1.95 km2 and claimed 36 lives. Although different discrete element methods have been applied to simulate the postfailure behavior of the Chiu-fen-erh-shan landslide in the last two decades, the lateral and dip-slope rock movements, the impact

Understanding mechanical behavior at the soil–structure interface is fundamental for safety in engineering and is therefore an important consideration in structural design. Buildings can be deformed or severely damaged by shear forces from the action of earthquakes, waves, or winds. It is therefore necessary to understand the conditions which lead to structural failure at the soil–structure interface

On June 24, 2017, a catastrophic rock avalanche with a volume of 5.08 × 106 m occurred in Xinmo village, Maoxian County, Sichuan Province, SW China. Several studies focusing on the triggering factors, failure mechanism and dynamic process of the Xinmo landslide have been reported in the literature. However, there are few studies with detailed three-dimensional investigations based on numerical modeling

The co-seismic landslides and rock avalanches caused by the 2008 Wenchuan earthquake generated numerous poorly consolidated deposits over a vast area. Rainfall-induced initiation and remobilization of these deposits have resulted in many post-earthquake disasters, such as rapid erosion, flow slides, and debris flows, threatening the local residents. The hydraulic properties of the deposits dominate

This work proposes a theoretical framework for the permanent deformation calculation of unsaturated granular materials. The approach is based on the separation of the Soil Water Retention Curve (SWRC) into three linear phases. This representation makes unique the wetting and drying paths with a newly defined normalized suction s/s*. The same unique curves of permanent deformations with the normalized

The United States witnessed its deadliest landslide on March 22, 2014 in Oso, Washington. Forty-three people were killed and the direct financial damage exceeded 170 million dollars. The topography of the slope prior to this landslide was complex due to the occurrence of several historical landslides on the same slope and three-dimensional (3D) features of the slope. This paper utilizes an inverse

Compacted bentonite-sand blocks have been proposed to construct buffer barriers in high-level radioactive waste (HLW) repositories in order to isolate wastes. The bentonite-based blocks are usually manufactured by uniaxial compression in mould and exhibit anisotropic behavior, which may influence the buffer performance. This current paper aims at investigating the anisotropic hydro-mechanical behavior

Recent advances in satellite geodesy have improved our ability to map and monitor landslides globally with unprecedented resolution. Differential interferometry of space-borne synthetic aperture radar (DInSAR) imagery plays a major role in identifying surface displacements associated with slope instabilities and monitoring their spatiotemporal evolution. However, this technique involves several constraints

A loose slope structure and multiple free faces in a step-like landform are important engineering geological factors that cause multistage landslides. Tensile cracks that develop inside the slopes and the free faces created by excavation will have an impact on determining the location of potential multistage sliding surfaces. However, it is difficult to accurately locate sliding surfaces with tensile

Packer test is a tool that has been long developed and widely used for characterizing the permeability of formation. The flow in the tested formation tends to transition from laminar to non-Darcian regime with increasing flow velocity and hydraulic gradient. But as the non-Darcian effect becomes important, how the borehole inclination and groundwater level influence the interpretation of packer test

Freeze-thaw (FT) cycles in cold regions have a huge effect on the stability of surrounding rock. Sandstone in the Tongchuan area of northwestern China was used as the research object to study the changes in physical and mechanical properties of rocks after FT cycles. After analyzing the force of the internal pore boundary of the rock, it is found that the internal large pores are more likely to make

Thixotropy of soil is, after softening by remolding, a process of time-dependent return to a harder state under constant water content and constant volume conditions. This paper presents a critical review of previous investigations on the thixotropy of soft clay. Thixotropic behavior is primarily a structural effect accompanied by the spontaneous dissipation of excess internal energy, and some microstructural

The Integration of conventional 3D seismic data with high-resolution 2D seismic data and cone penetration test (CPT) data from geotechnical jack-up foundation reports has enabled a new late Quaternary geotechnical stratigraphy for the Southern Danish Central Graben area in the North Sea. The shallow subsurface has been subdivided into geotechnical units based on seismic appearance and soil behaviour

The FEBEX in situ test provided bentonite samples that had been submitted to the conditions of the engineered barrier of a nuclear waste repository for 18 years. These samples can be considered quite evolved from the microstructural point of view (aged, matured) when compared with samples prepared in the laboratory under shorter and more usual time scales. The barrier, composed of bentonite blocks

The Avignonet landslide in the Trièves area is made of Quaternary paraglacial sediments among which imbricated till, glacio-lacutrine and fluviatil layers. Numerous boreholes (drillings and corings) were conducted during the mid-1980s and the mid-2000s to assess the geological and geotechnical setting of the inhabited, southern part of this slow-moving earthslide. Heterogeneous paramaters available

Ex-ante and ex-post assessments are both essential in risk management, although ex-post assessments of engineering measures have not been widely reported. In this study, an ex-post benefit-cost assessment method was developed to enable the direct impact of remediation engineering measures for debris flows to be quantified. We propose three categories of parameters for calculating benefit and cost:

To investigate the seismic cumulative failure effect (SCFE) of a reservoir bank rock slope, the dynamic displacement response of the slope was analysed using shaking table tests. A plastic effect coefficient (PEC) is proposed to reflect the plastic deformation degree of the slope under the influence of earthquakes, and its applicability in analysing the SCFEs of slopes is verified by using the Arias

The aim of this paper is to demonstrate how the integration of differential interferometric synthetic aperture radar (D-InSAR) and levelling improves the monitoring of ground deformation phenomena, thereby enabling their complete understanding. The complementarity between D-InSAR and levelling is illustrated through a case study of the construction of a road tunnel beneath Glòries Square, Barcelona;

This study presents a multi-disciplinary approach for combining geological-geomorphological field mapping with different surface deformation monitoring techniques (i.e. extensometer, tachymetry, photogrammetry, airborne laser scanning (ALS), terrestrial laser scanning (TLS), uncrewed aerial vehicle (UAV)) to evaluate the impact of structural features on the formation process and deformation behaviour

Rockfall hazard in mountainous areas requires the construction of protective structures for the buildings or transport facilities. Reinforced soil embankments can be effective protections against rockfalls due to the combination of the damping characteristics of the soil and the tensile resistance of the reinforcements. Following the advances in soil reinforcements, the research is ongoing for this

The physics of water imbibition into initially unsaturated sandstone is critical to the understanding of displacement processes and fluid transport in the vadose zone. The distribution of water within rock is important due to its significant influence on rock mechanical behavior. Here, therefore, we used nuclear magnetic resonance (NMR) technology to visualize and quantify the dynamics of water infiltration

Local site effects can amplify seismic shaking and damage caused by earthquakes. Site factors (SF) are used in seismic design to account for these effects to modify ground motions from a reference rock site. Average shear wave velocity in the top 30 m of soil (Vs,30) is typically used to predict SF. However, recent studies have shown that using Vs,30 alone may be insufficient in quantifying SF under

The Upper Cretaceous to Lower Paleocene Chalk Group in the North Sea comprises important reservoir targets for hydrocarbon and energy storage. The quantitative impacts of mineralogy, chalk diagenesis and oil saturation on petrophysics are often based on general trends that cannot be directly applied to reservoir engineering. The present study aims at identifying quantitatively the individual effects

The occurrence of rainfall-induced slope failures is mainly due to the infiltrated rainwater which reduces the shear strength of soil. The slope is initially observed in an unsaturated condition and it becomes wetted during rainfall. In other words, the infiltration of rainwater into the soil slope is a wetting process. As a result, the amount of the infiltrated rainwater is mainly governed by the

Traffic loads induce cyclic loading under influence of environmental factors, and is affected by the variation of moisture content and suction (s). These parameters are difficult to quantify, and the methods for determination are cumbersome. This paper presents extensive experimental studies used to obtain the resilient modulus-suction (MR-s) relationship of the treated subgrade soil. An optimum design

Predicting the geomechanical behaviour of rockmasses is key to the economic success and safety of rock engineering projects including surface and underground excavations. For these projects, unconfined compressive stress (UCS) laboratory testing provides fundamental geomechanical properties of intact rocks. It is currently standard practice for UCS testing to consider only homogeneous specimens that

Prediction of the area of possible inundation is critical for debris-flow hazard management. This is typically done with inundation modeling programs, but many of these models are not specific to predict post-wildfire debris flows, a particularly dangerous subset. For this research, deposition patterns from flows triggered by the 2003 Christmas Day storm in areas burned by the Old and Grand Prix Fires

Detailed knowledge of the behaviour of rocks under thermal stress is essential in a variety of fields such as the exploitation of oil and mineral resources, the geothermal sector, the storage of radioactive liquid waste, or even CO2 capture and storage. Granites are widely studied and exploited in these fields, and they show different reactions to high-temperature and thermal cycles due mainly to their

Mapping of structures, such as discontinuities, in an exposed rock mass is fundamental for slope stability analysis. This study investigates mobile laser scanning technology to identify structural discontinuity in a complex environment where the exposed rock face is partially covered with vegetation. The conventional terrestrial laser scanning and photogrammetry based approaches for structure identification

Temperature is one of the key factors affecting the permeability of water flow in loess, influencing its stability and, consequently, its geohazard potential. The traditional temperature calibration formula(TTCF) is widely used in the literature for calculating the permeability at some temperature, based on the permeability at 20 °C. However, its suitability has not been verified, especially for water

Mountainous regions are inherently susceptible to geohazards, such as landslides and debris flows, with the threat of natural disasters compounded by human activities (mainly settlements). Lessons learned from past events that involved the interactions between human activities and geohazards are helpful for future site selections of human settlements in mountainous regions. To this end, the events

Age is of great significance to understanding the causes of landslide instability and movement, and therefore, it is important to know when conducting a hazard assessment. To date, no detailed and comprehensive determination of the age of the Mahu giant landslide has been conducted. The Mahu giant landslide is located in the lower reaches of the Jinsha River and has a volume of 2.38 km3 and a maximum

Leitai is a cultural relic site consisting of a loess platform built during the Qianliang dynasty (1700 years ago), Han dynasty tombs (1800 years ago) built on the lower part of the loess platform, and the Leitai Taoist temple built on the upper part of the loess platform during the Ming dynasties (500 years ago). Thus, this site has considerable historical and cultural research value. Over hundreds

Podhale is a region in Poland at high risk of landslide. Sudden activation of landslides is the greatest threat to the local infrastructure. This work describes the joint use of electrical resistivity tomography (ERT) and aerial photogrammetry in the study of the active “Bachledzki Hill” landslide. In order to determine landslide dynamics, a digital version of stereo-pairs of aerial images from 1972

This paper presents a laboratory experimental investigation on the membrane behavior and diffusion properties of sand/sodium hexametaphosphate (SHMP)-amended bentonite backfill (referred as SHMP-SB backfill) in vertical cutoff walls for containment of lead-contaminated groundwater. A multi-stage chemico-osmotic test was conducted on the SHMP-SB backfill sample using lead nitrate (Pb(NO3)2) solution