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The role of ornithogenic factor in the formation of soils and soil cover patterns in continental and maritime Antarctica is considered. The results of long-term soil studies at key sites in coastal oases of East Antarctica (Larsemann Hills, the Haswell Islands) and on the Subantarctic islands (King George Island, Livingston Island, the Argentine Islands) are summarized. The influence of the penguin rookeries on the morphology and physicochemical properties of soils is shown. These rookeries determine the vast spatial zones of biogeochemical influence on the environment around themselves. Special attention is paid to the phenomenon of ornithochory, which is maintained by the flying seabirds (skuas, albatrosses, terns, petrels, etc.) and is manifested in redistribution of vegetation, soil material, and meso- and microbiota to the areas that were previously free of vegetation and soil cover (periglacial areas, fresh moraines, rocky outcrops, etc.).

Rainfall is one of the most significant natural factors for inducing landslides. The shallow saturated zone formed in slopes during rainfall is an important factor in inducing shallow landslides. In this paper, the characteristics and influencing factors of the saturated zone in soil slopes, and the relationship between the soil surface permeability coefficient and the rainfall intensity are analyzed. In this research, the equation that characterizes the rainfall intensity by the soil saturation is built based on the Mualem-van Genuchten model, which mathematically describes the soil water characteristics of unsaturated soils. Using this model, the target saturation of the slope surface during rainfall can be determined accurately, with an average deviation of − 0.008. Based on the equations, the innovative critical curve model of the rainfall intensity−time required to form the shallow saturated zone is established and calculated. The influence of the soil material, slope angle, rainfall intensity and antecedent rainfall on the critical curve for the shallow saturated zone is analyzed. The results indicate that for slopes of 30°~40°, it is easy for the shallow saturated zone to form, and the previous rainfall after more than 16 days has little impact on the critical curve. Furthermore, an innovative landslide prediction model, based on the critical curve for the shallow saturated zone and I-D modeling, is proposed to provide benchmarks for the prediction-specific characteristics of deep or shallow landslides, which is verified by the case of the Madiwan landslide.

To explore the effect of drain board spacing on the vacuum preloading treatment effect, transparent soil material was selected to carry out indoor vacuum preloading model tests, and particle image velocimetry (PIV) technology was used to obtain the displacement field inside the soil under different drainage spacing. In this paper, a mixed solution of amorphous silica fume, white mineral oil and n-dodecane was used to prepare transparent soil, and model tests of vacuum preloading transparent soil were carried out under drainage spacing of 200 mm, 300 mm, and 400 mm. The test results show that the displacement field of soil with different spacing of drainage is obviously different. Obvious "concave" settlement will occur on the soil surface under 200 mm spacing, and obvious "W" type settlement will occur under 400 mm spacing. 300 mm is the best spacing of drainage; the range of the "soft soil zone" is small, and the uneven settlement of the soil surface is not obvious. According to the influence range of a single drainage, the spacing of drainage should be reasonably designed to ensure the lap and connection of "soil piles" and improve the effect of vacuum preloading treatment.

The instability of soil slopes is directly related to the shear parameters of the soil material and groundwater, which usually causes some uncertainty. In this study, a novel method, the e...

The work presents the results of research on erosion and landform changes of a bottom of a dry erosive-accumulation valley in Elizówka in 1958, 1970 and 2016. The changes have been examined with the use of geodetic topographic surveys techniques. The research field was a 480-metres long part of the valley bottom. The topographic surveys in 1958 and 1970 were conducted with longitudinal (parallel to the bottom of the valley) and cross (every 20 metres) sections method. In 2016 the modern measuring devices were used. All the results, together with coordinates of points and historical data were converted into GIS spatial layer. The altitude values formed the input data for interpolation of rasters showing changes of the topography in three periods. Three TIN models were also developed to distinguish erosion and accumulation zones plus the quantity of eroded and accumulated material. The valley on the majority of its length has been raised and has changed from V-shaped into U-shaped. Accumulation of the soil material led to levelling the bottom. Accumulation concentrates along a flow line, while soil washout mainly at the bottom of slopes. The thickest sediment layers were observed in the lowest part. For the whole 1958-2016 period a total of 3470 m3 soil material has been deposited on the area of about 1.62 ha, while in the same time only 130 m3 has been eroded (from 0.22 ha).

Rock freezing affects the soil complexes under maximal temperature gradients and forms a set of specific cryotrasological features in the solid soil matrix. When preserved these features serve as direct or indirect indicators of the past cryogenic conditions. Transformation of soil material on macro- and microscale belongs to the direct indicators whereas gleying in the well-drained positions, conditioned by the permafrost waterlogging is an indirect indicator. A variety of these features observed in the paleosols to the north of the European and West Siberian Loess belt was used by the authors to reconstruct the cryogenic environments of the late Pleistocene.

This research conducts dynamic time-history analysis and a modified cross-section racking deformation (MCSRD) method to analyze the collapse mechanism of the Daikai Subway during the 1995 Kobe earthquake using FLAC2D. A simplified approach to consider the nonlinear behavior of a structure element is imported and combined with the FLAC2D built-in nonlinear soil constitutive models to accurately consider the nonlinear interaction between the soil material and structure. Based on the proposed framework, the damage evolution process of the Daikai Subway station can be traced by the dynamic time-history analyses. The collapse pattern roughly agrees with field observation. Regarding the MCSRD method, the critical member of the “central column” is identified but the internal forces did not reach its limit state; this may be because inertial force is neglected, which is a characteristic of the pseudo-static method. Therefore, it is recommended to conduct dynamic time-history analysis for a shallow buried tunnel in soft soil because the inertial force may largely influence the seismic characteristics.

Results of a detailed analysis of pedosediments—sediments composed of transported material of soil humus horizons—are discussed. Five main morphological features of pedosediments attesting to the origin of the transported soil material are identified; their allocation to certain types of pedosediments is shown. A map of pedosediments for a small catchment in Tula oblast has been developed on the basis of their morphological analysis. Three types of pedosediments are specified by their morphological features and location: (1) leveling, filling depressions; (2) covering, extending on the slopes of the ravine; and (3) protruding above the surface of the slope represented by “napash”—agrogenic earthwork at the edges of fields. The covering pedosediments formed on the slopes are shown to be predominant both by area (60%) and by the volume of accumulated material (45%). The leveling pedosediments at the bottom of the ravine occupy 25% of the area and retain about 35% of all sediments of the small catchment. Only 2% of the total material of pedosediments in the catchment belongs to protruding pedosediments. The formation and localization of these pedosediments are controlled by the formation of napashes. In general, the material of pedosediments redistributed within the small catchment constituted about 12% of the total mass of humus horizons of the soils-donors. Pedosediments play a significant role in the soil cover and occupy about 10% of the total catchment area.

This paper provides a record and analysis of a site in east-midland England, at which organic and soil material are found between two Middle Pleistocene tills. This is the first discovery of its kind in the area, and demonstrates unequivocally that the region was glaciated on two separate occasions, something that has long been inferred and articulated, but not actually demonstrated. The landforms, sediments and soils are studied with respect to their geomorphological, lithological, pedological, palaeobotanical and structural properties. The organic and soil material along with soil structures indicate, sequentially, a periglacial climate, a long period of warm temperate weathering and a cool temperate climate. Evaluation of this evidence in terms of existing published work identifies a number of problems with existing models and suggests that the most likely model for the glacial history of this part of midland England is an early Middle Pleistocene glaciation which is represented only by trace erratics, a Marine Isotope Stage (MIS) 12 age glaciation which moved across the area from the NW and deposited a chalk-free till, and an MIS 8 age glaciation that transported and deposited an upper chalky till from the NE.

An expansive soil slope of a high-speed railway under construction in Yunnan suffered a local collapse after a heavy rainfall. The expansive soil on this slope surface is prone to slip and collapse under the action of rainfall. The analysis of water sensitivity reveals the attenuation law of the shear strength of the expansive soil. With the increase in the water content, the shear strength of the expansive soil decreases significantly. Wet–dry cycles also significantly lower the shear strength of the expansive soil. In addition, a high-density electrical method test is performed on the expansive soil slope to determine the structural characteristics of the internal soil. The test results indicate that the internal soil of the slope exhibits poor mechanical properties and contains fissures and cracks, which are also the factors that caused the landslide. The finite element software, ABAQUS, is used to analyze the impact of rainfall on the expansive soil slope. The results reveal that the soil at a depth of approximately 2 m below the surface reaches complete saturation after 24 h of rainfall, and the plastic failure zone is mainly distributed on the surface and toe of the slope. Based on the electrical test results, the slope soil material is classified into saturated, fissured, and non-fissured soil zones. The stability analysis results reveal that the sliding surface is circular and in the shallow layer of the slope, and the sliding depth is 2–3 m. Although the depth of the landslide mass is not large, almost the entire slope surface soil undergoes plastic failure, resulting in a large area of ​slippage.

Analysis of an earthen dam, especially its slopes, is very important these days as its failure may cause huge loss of lives and properties. These days numerical models are used to check the stability of an earthen dam. Numerical models simulate all the parameters, which affect the safety of an earthen dam. The most important parameters are properties of the soils used for the construction of an earthen dam. For the numerical modeling in this study, a finite element analysis software is used, i.e. GEOSTUDIO 2007 (SEEP/W and SLOPE/W). The parameters considered in this analysis are the site and its foundation conditions, soil material characteristics and hazard potential associated with the particular site. To find the factor of safety, a numerical model of SLOPE/W and SEEP/W program of GEOSTUDIO software is tested for steady-state condition and sudden drawdown. The Morgenstern-Price method, based on limit equilibrium, which is incorporated in SLOPE/W to analyse the model for four cases, namely earth dam without berm and without a toe drain, earth dam with berm without a toe drain, earth dam without berm with a toe drain and earth dam with berm with a toe drain. The results showed that out of four cases, the best case to improve the factor of safety of the slope is the fourth case, i.e. earth dam with berm with a toe drain.

The discrete element modeling of rock and soil mass usually relies on tedious parameter adjustment and mechanical property testing operations to obtain appropriate mechanical parameters of the element. In this paper, based on the linear elastic contact theory, a discrete element model of rock samples was established based on discrete element software MatDEM with high-performance numerical analysis, and the actual mechanical properties of the model samples were predicted using a machine learning method, XGBoost algorithm. A certain amount of sample data sets was generated, and through numerical experiments, training, validation and test operation of the rock mechanical properties (compressive strength, Young's modulus, Poisson's ratio and tensile strength), the numerical model quantitative relationship between the actual and input mechanical properties was explored, showing the following results: (1) Based on the characteristics of the model 12000 rock samples and correlation analysis, the tag data shows that the input mechanical properties are positively correlated with the actual mechanical properties;(2) With the increase of the number of samples in the sample training data set, the training average error becomes smaller and smaller, and the error distribution becomes more and more stable.(3) The training results converge to the set threshold, and the prediction errors of mechanical parameters are all less than 4%, and the error distribution is stable, which proves that the machine learning method can quickly and accurately establish the rock model with specific mechanical properties., IOP Conference Series: Earth and Environmental Science, 861 (3), ISSN:1755-1315, ISSN:1755-1307

The advancement of technology opens up new opportunities to soil micromorphology. Although a description using an optical microscope of the fabric and the various constituents of soils will be always necessary to investigate soil evolution, the uncovered thin section leaves soil material on which analyses can be performed. Since the 1970s, it was possible to observe thin sections at high resolution with the scanning electron microscope in its backscattered electron mode (see “10.1007/978-3-030-67806-7_1#Sec7”). It was also possible to generate chemical images with electron microprobes. But these conventional techniques, as well as new ones, greatly improve the study of matter interactions in soils, not only by enhancing the spatial resolution with incredible precision but also by providing chemical and mineralogical images, which substantially increased the accuracy of micromorphological diagnostics. By coupling morphological and chemical approaches, including stable isotope imaging in soil material, the future of soil micromorphology will undoubtedly offer new opportunities to solve specific problems, especially in the field of organomineral interactions in soils. It is wise to say that soil micromorphology, with its analytical and holistic approaches, will make it possible to build the necessary solid foundations needed for investigations that are increasingly oriented towards nanoscale objects: it will remind us that the trees should not hide the forest.

In this study, large-scale triaxial compression tests are conducted on gravelly soil material. The experimental investigation shows that gravelly soil exhibits complicated volume-dilatation/contraction behaviours that are dependent on stress level. To better describe the mechanical behaviours, an elastoplastic constitutive model is proposed within the frameworks of generalised plasticity and the critical state soil mechanics. An evolution equation of the void ratio is incorporated into the model to describe the effect of a relatively dense or loose state on the volume-change behaviours. The model has 10 material constants that could be determined using a few large-scale conventional triaxial tests. The model is then used to simulate the mechanical behaviours of gravelly soil. Comparisons between the numerical simulations and the test data show that the model is capable of capturing the mechanical behaviours of gravelly soil under various confining pressures. This research can be beneficial for understanding the mechanical behaviours of gravelly soils.

Little is known about how Fe-Mn nodules vary in relation to pedogenetic horizons in soils derived from loess. In this investigation nodules were collected according to soil genetic horizons from a Fragiudalf in loess at Southeast Purdue Agricultural Center (SEPAC) in Indiana and physical, chemical, micro- and macromorphological features of nodules and their soil matrix were determined as a function of soil depth. The quantity, chemical composition, and micromorphology of the nodules varied with genetic horizons. The Ap horizon was found to contain the largest amount by weight of nodules (25.43 g/kg) and this was likely due to soil erosion. After the Ap horizon, the 2Btx1 and 2Btx2 horizons had the greatest content of Fe-Mn nodules by weight. Nodules had lower concentrations of SiO2, Al2O3, K2O, TiO2, MgO, Na2O, and CaO; in contrast Fe2O3, MnO, and P2O5 in nodules showed clearly greater concentrations than that in the corresponding soil material. The SiO2 content decreased with nodule size whereas Fe2O3 and MnO increased. The least depletion of SiO2 in nodules of 1–2 mm (N2) and 0.5–1 mm (N1) was in the Bt2 horizon, and was greatest in the 2Btx2. The Al2O3 had accumulated in the N2 and N1 nodules within the Ap horizon and in the N2 within the 2Btx2 while other horizons were depleted of Al2O3. Brown nodules had a small Mn/Fe ratio ( 1). The internal morphology of the nodules also varied with Mn/Fe ratios. The fungal hyphae or bacteria resulted in honeycomb, cell, cone, or dendritic structures. The cell and cone morphology required large Mn/Fe ratios, low pH, and high content of Ald. The scanning electron microscopy (SEM) analysis illustrated an elemental distribution trend such that the Mn was centralized in the nodule internal structure; whereas, Fe was concentrated towards the exterior. The band structure of nodules likely formed in response to seasonal wetting and drying as an accretionary process. Three basic formation stages for a well developed nodule can be inferred which correspond to different soil forming environments: 1) Fe enrichment for nucleus formation in wet soil, 2) Mn enrichment in an intense dry soil, and 3) Fe banding enrichment in a slightly dry soil. Nodule formation occurred synchronously with soil pedogenesis and can therefore be used as a proxy for understanding soil pedogenesis and the environment under which it occurred.

Archaeological studies are usually based on human-made artifacts or other remains of human activities. Where no such materials are preserved, soil properties can be used to detect past human activities. Archaeologists found some conspicuous features formed in a loess-paleosol succession comprising a sequence of Luvisol Bt horizons at the Shenyang Agriculture University Paleolithic Archaeological Site. The purpose of this study was to analyze the soil properties inside these features and in the surrounding soil material, to judge whether the soil features were related to human activities or not. Particle size distribution, major element composition and rare earth element contents inside the soil features and in the surrounding material were used to test the uniformity of the material inside and around the features. Soil organic carbon content, magnetic susceptibility and available phosphorus at the soil depth where the features occurred were used as indicators of potential human influence. Results showed that the conspicuous features had the same type of loess-like parent material as the surrounding soil, and also their chemical properties did not point to any human activities. We found two genetically different types of features. One type represents an initial stage of fragipan formation, whereas the other resulted from redox processes caused by perched water. In conclusion, this study proved that the soil features were not formed by human activities but by pedogenesis. Our approach is generally applicable to similar cases and research questions.

Background Three groups of factors related to topography, geology and hydrology have influence on the triggering of shallow landslides in soil material. In this paper a single representative factor (T-factor) for the topography is proposed, which can be used to define threshold values for the possibility of shallow soil slides. This study was carried out in the Dayi area, Guizhou Province, China. During a heavy rainfall event on June 6, 2011, 230 shallow soilslides were triggered. In some slopes, no shallow landslides were triggered even though some of the topographical factors point to unstable high probability. Results We isolated and analyzed the influence of the topography on the triggering of shallow landslides in catchments with almost identical hydrological and geological conditions and propose a new T-factor as a topographical indicator which is a combination of the slope angle, the upslope contributing area, the cross-section, and the free-face of a (potential) shallow landslide. Higher T-factor values are related to higher probabilities of shallow landsliding. The probability assessment with the topographical factor T was successfully validated in other areas of the USA and Japan. Conclusions Without information on the geological and rainfall conditions, a quick and primary prediction of shallow landsliding using the topographical factor T is proposed. Additionally a new R-factor is proposed as a rainfall indicator, which is a combination of the 1 hour rainfall and cumulative rainfall before the landslide event and the annual rainfall. Higher R-factor values are generally related to higher probabilities of shallow landsliding. The primary probability factor P, which is the combination of T and R, gives a final indication of the probability of shallow landsliding.

Introduction: Due to the fact that the model experiment can simulate the flow process and movement law of fluid during the seepage experiment, seepage model experiment was widely applied to study the hydraulic characteristics of rock-soil mass and transportation of ground water and pollutants. While due to the opacity of the model medium in traditional seepage experiment, the flow process, diffusion law and occurrence state of fluid can not be observed intuitively during the experiment. Method: A new technique of seepage model experiment based on transparent rock-soil material (TRSM) was introduced in this paper, combined with optical observation method, digital imaging process technology and tracer technique, so as to realize the visual observation of seepage process. Results: The advantages and disadvantages compared with the traditional experiment were analyzed and the theoretical foundation for carrying out the seepage experiment based on TRSM was established.

The article describes various methods of assessment of load-bearing capacity (reliability) of a pile as a main element of pile foundation. It is shown that deterministic, probabilistic and possibilistic methods have a number of advantages and limitations. An actual task is to develop new approaches to assessment of foundations load-bearing capacity. The combined method providing the optimal assessment according to the given examples is developed in the article. Some features of the proposed methods are in the probability and possibility theories application to account uncertainty or incompleteness of initial data in quantifying the reliability of a pile. Presented in the article methods for a quantitative assessment of single piles reliability can be used for more complex computational models, including multielement pile foundations and more complex models of soil foundations. These methods have not been applied to piles reliability research so far and the article pre-sented is a pioneering one and has no analogues known to the authors.

Stress reduction factor, λ, is a dimensionless coefficient in two-dimensional (2D) analysis based on convergence confinement method (CCM) of tunnel which represents stress relaxation in the tunnel walls at different excavation steps. The aim of this paper is to look into the influencing factors on parameter λ around the tunnel walls using finite difference code in order to improve the accuracy of the CCM. For this purpose, four different ground types with various tunnel radii, depths and cross section shapes are considered. Finally, the 2D analysis using uniform and variable stress reduction factors determined in this paper is compared with the 3D analysis of the tunnel. The results of this study enhance our understanding of the role of geometrical and soil material parameters of tunnel on stress relaxation around tunnel walls. The tunnel depth, soil type and tunnel shape have great influence on λ. Variable stress reduction factor enables the convergence–confinement method to predict the realistic behavior of third dimension of the tunnel and can also be used as the best alternative to 3D models.

The deposition of excavated natural soils, e.g. in open pit mines or during land reclamation, produces in general lumpy soils with multimodal pore sizes. The mechanical behaviour of such soils is determined by interaction between the firm to stiff lumps and the soft to liquid soil material in the macrovoids between the lumps. The initial skeleton composed of lumps resembles a coarse grained soil. However, contrary to mineral grains, the macrograins (lumps) are not incompressible and time-independent. Due to rising overburden during the subsequent deposition of the excavated soil, a time-dependent deformation of the lumps takes place, being accompanied by a softening of the lumps’ surface. The space between the lumps, originally occupied by air, becomes gradually filled with that soft material. A constitutive description of the lumpy soils should take into account all the mentioned effects. In this paper, main ideas and fundamentals for the constitutive modelling of the relevant phases of lumpy soils are outlined. With help of a homogenization method, a material model suitable for practical applications can be obtained.

The yield criterion parameters of the soil material change with different values of the cohesion and the angle of frictionbecause of sustained rainfall infiltration. Based on the Mohr-Coulomb (M-C) and Drucker-Prager (D-P) yield criteria, some reasonable yield criteria selections were discussed for quantitative analysis of unsaturated soil slope stability. Moreover, a critical point was found at the effective angle of friction equaling to 16.5° by transformation of parameters related to unsaturated soil under sustained rainfall. When the effective angle of friction more than 16.5°through parameter transformation of different yield criteria under natural condition, the calculation result of the safety factor was such that: f(DP1) > f(M-C) > f(equivalent M-C) > f(DP2) > f(DP3). While the effective angle of friction less than 16.5° , through parameter transformation, the safety factors were in the following order: f(DP1) > f(M-C) > f(DP2) > f(equivalent M-C) > f(DP3). The calculated results from a case study showed that the equivalent M-C yield criterion should be the best at evaluating soil slope stability before rainfall; the DP2 yield criterion should be selected to calculate the soil slope stability at the effective angle of friction less than 16.5°under sustained rainfall. The yield criterion should be selected or adjusted reasonably to calculate the safety factor of unsaturated soil slopes before and during sustained rainfall.

Different hypotheses about the genesis of gilgai microtopography and corresponding soil complexes with clayey swelling soils are considered in this review. Their diversity is stipulated by specificities of the objects themselves and by the history of studies of the composition, properties, regimes, and landscape conditions of the areas with Vertisols in different countries. Most of the hypotheses about the genesis of Vertisols with the gilgai microtopography suggest that strong swelling–shrinking processes take place in these soils in the course of moistening–drying cycles; the origin of shear stress in the soils, its spatial patterns, and the particular ways of translocation of the soil material are discussed. At the early stage of Vertisol studies, a hypothesis about the leading role of the process of “self-swallowing” of the soils as a result of filling of open cracks with the material from the upper soil horizons was popular. However, numerous facts suggest that the intensity of this process is relatively low, so that it cannot play the major role in the gilgai formation and cyclic changes in the thickness and properties of the soil horizons in Vertisols. Another important mechanism is the uneven moistening and drying of the whole soil volume resulting in the irregular distribution of inner tensions in the soil with the development of shear stress and plastic deformation of the soil mass. The hypotheses suggested in the recent decades are based on the models of soil mechanics. A number of hypotheses consider possible alternation and duration of evolutionary stages of the development of Vertisols with the gilgai microtopography.

Project relevance: For construction of roads and embankments, soil material must be compacted to its densest state, which will result in higher soil strength and long-term stability. To obtain the compaction characteristics of soil, engineers conduct a series of laboratory standard compaction tests and then use these data for field compaction. In this project, an embankment will be built as part of a pre-load method to consolidate the soft alluvial clay (more details about consolidation are given in Chapter 10) using the sand from Pit 1. We are required to interpret and analyse data from compaction tests on this sand. This section will introduce the concept of soil compaction and discuss how to determine compaction characteristics of soil.

The focus of this investigation lies in the qualitative and quantitative evaluation of the density changes in the direct vicinity of a pile installed by means of vibratory driving. This is visualised using an experimental model set up which allows image recording of changes in the granular soil material with a high geometric resolution. This is enabled by fitting the model test container with a large glass panel and installing a halved section of a steel pile with its cut edges directly along the glass panel. The Digital Image Correlation method (DIC) is applied in order to identify zones of density changes around the pile shaft during installation. Results show that different zones of densification and compaction develop around the pile shaft and that these zones differ again in there values between the inner and outer pile. The magnitude and expansion of these zones can be accurately determined which allows a transfer of the results to further numerical investigations. This experimental investigation aims to take a novel approach of allowing the refinement of the numerical soil model for the loading analysis by supplying the actual void ratios after pile installation. This will give a more realistic deformation behaviour as changes in the soil structure due to the installation are taken into account prior to loading.

Nowadays, expansive or swelling soils considered as a worldwide issue which poses several challenges to geotechnical engineers. Expansive soils are classified as a high-plasticity fine grained soils which mainly consists of clay minerals. This paper is intended to investigate the expansive soils characterizations along Tabriz Northern Highway (TNH) and their destructive effects. TNH with length of 17 km is constructed about 10 years ago. Geology formation of TNH and its around is consisted of different layers of mudstone, marlstone, and sandstone. The expansive soils formation is result of weathering of these rock layers. There are some challenges for TNH pavement such as: longitudinal and transverse fractures and cracks, the distortion and settlement of surface which is cause many accidents. Field studies are shown that the main reasons of TNH pavement problems are soil swelling and settlement of fill soils below pavement. For investigation of swelling characterization of soils, some samples were obtained and tested in laboratory. The test results indicate that the unified classifications of soils are mostly CL and clay material of soils is about 30%. Plasticity index of soils is placed between 7 and 23%. Swelling potential of soils along TNH is evaluated low to medium. In order to ground treatment, soil-cement is placed under road using the local soil material.

This research simulates vertical bearing capacity of Prestressed Concrete piles by the theory basis of finite difference method and relevant material constitutive model for its capacity can be affected by soil plug effect significantly. Its Q-s curves are acquired and analyzed. The research indicates that load-settlement relationship of PC piles is proportional function basically within its bearing property. Also the advantages of FLAC3D software are affirmed when analyzing piles settlement problems.

For the purposes of defining the parameters of the model behavior 'Koševo layers' geomechanical laboratory tests were performed such as classification test and deformability test in oedometar test and shear strength test in consolidated undrained conditions (CU test) and in consolidated drained conditions (CD test). Simulation of triaxial test in software package Plaxis was performed with several models. Model simulations with application of different models of soil behavior is trying to find out which model best supports the model behavior of the tested soil material. The paper presents the results of simulation of triaxial CD test with Soft Soil model in software package Plaxis, based on finite element method and a comparison with laboratory results.

The ‘Sailing Rocks’ of Death Valley, California are known worldwide, and the enigma of how they move over a desert ground without intervention of animal or human forces, still remains one of the great natural mysteries. There exist different theories about how these movements happen, the most recent was that ice-rafts build up below and around the rocks, which are then pushed forward by moving ice floes. Earlier theories regarding this phenomenon describe the influence of wind, and flows of melting water on fine soil material (Hypothesis of ‘Sailing Rocks’). We describe here the same phenomenon, observed not in a large rock weighing several hundreds of kilograms, but in a small pebble of about 2 cm in size. A clear analysis of the conditions under which its movement took place has allowed the formulation of the minimum conditions under which a rock starts moving. Ice rafts may be sufficient but are not necessary. Here we show that pebbles sail driven by the wind over a watery surface that covers an icy but water saturated substrate, similar to an aquaplaning car. The same physical rules apply whatever the scale, to this small system as well as to the large sailing rocks of Death Valley.

Severe and repeated earthquakes devastated Cyprus in antiquity, causing in many cases the abandonment of entire settlement sites. Yet, information regarding the level of seismic activity of historical seismicity in Cyprus is very limited and does not provide the evidence to arrive at reliable conclusions relative to hazard damage parameters such as the severity or occurrence frequency of a seismic event. Thereafter, the level of risk in which these monuments are exposed is unclear leading to an increased uncertainty regarding their safeguarding from future events. The paper aims at investigating the correlation between damage observed in underground ancient tombs and the historical seismic activity at the area based on in situ observations and expert opinion analysis. In addition, the paper aims to simulate the current state of the tomb's structure, and predict, through a seismic scenario, the propagation of damage from future large earthquake events. Underground monuments are chosen since, due to the nature of the seismic force, they are further “protected” and capable of surviving strong ground motions as they follow the displacement of the soil surrounding them. Typical examples of such structures in Cyprus are the hypogea in the necropolis of the “Tombs of the Kings”, located in Paphos area. Some of these monuments exhibit severe cracking of the rock-cut stone walls and evidence of collapse of vertical resisting members of skeleton structure. Paphos area is the most active seismic region in Cyprus based on the historical catalogue of events with evidence of a number of destructive earthquakes. The framework presented herein utilizes information regarding the current geometry of these structures as documented from topographical surveys, their depth, area of opening, size of resisting members along with information regarding the geotechnical conditions at the site to arrive at estimates of the displacement demand under various seismic scenarios. The predicted shear strain levels on the walls are compared with the strain capacity under tension of the soil material to identify the possibility of propagation of cracking of the walls based on a specific seismic scenario.

The principle of effective stress based on unsaturated soil material model and the boundary conditions of rainfall infiltration on the slope are introduced. The numerical model is built according to the example, and then the ABAQUS finite element program, which is combined with fluid-solid coupling, is used to simulate the problem of transient seepage field caused by rainfall infiltration. With the powerful post processing functions ability of ABAQUS program, we can observe the variation law with the time of pore-pressure distribution and displacement field and equivalent plastic strain. Moreover, the effect on the stability of slope under rainfall infiltration is analyzed.

Surface runoff, soil loss, suspended sediment concentration (SSC), texture of eroded soils and suspended sediment were determined on slightly eroded chernozems (mouldboard fall-ploughed) during years with different amounts of snow in three areas of southern West Siberia (Predsalairye, Priobye and Kuznetsk hollow). These areas have different geomorphological and climatic characteristics and soils. Observations were made from 1969 to 2007. The soil loss during very low-snow and low-snow years did not exceed 2 t ha− 1. After winters with normal amounts of snow, the runoff led to slight soil loss (2–5 t ha− 1). Soil losses in high-snow and very high-snow years varied from slight to severe (4.8–15.8 t ha− 1) depending on studied area. The main sediment exported during intensive snowmelt and the 1 mm of runoff transported from 35 to 150 kg ha− 1 of soil material. The removal of soil particles

Sheet and interrill erosion areas are sources of soil material rich in nutrients and pollutants. The loss of soil, nutrients and other chemicals from these areas is a matter of concern both in terms of maintaining soil productivity and the health of offsite environments. Many experiments on rainfall erosion have shown enrichment of fine material, nutrients and other chemicals in the sediment discharged for sheet and interrill erosion areas, but often these results were obtained over short periods of time. A qualitative mechanistic model of raindrop-induced saltation is used to illustrate how this transport mechanism influences the composition of sediment discharged by rain-impacted flow. Initially, fast moving particles are enriched in the sediment discharge but, over time, during a rainfall event, slower moving particles become more represented. Raindrop-induced saltation promotes the storage of material on the soil surface with a coarser composition than the original soil. Winnowing of material from this storage by the development of flow-driven saltation during high-intensity events can modify the composition of the sediment discharged later by raindrop-induced saltation. Given stable soil particles, the composition of the sediment discharged at the steady state is the same as the original soil. Enrichment is a non-steady-state phenomenon and failure to recognize the transient nature of enrichment may lead to inappropriate interpretation of the implications of the results from short-term experiments. Copyright © 2011 John Wiley & Sons, Ltd.

Water collection from undisturbed unsaturated soils to estimate in situ water and solute fluxes in the field is a challenge, in particular if soils are heterogeneous. Large sampling devices are required if preferential flow paths are present. We present a modular plate system that allows installation of large zero-tension lysimeter plates under undisturbed soils in the field. To investigate the influence of the lysimeter on the water flow field in the soil, a numerical 2-D simulation study was conducted for homogeneous soils with uni- and bimodal pore-size distributions and stochastic Miller-Miller heterogeneity. The collection efficiency was found to be highly dependent on the hydraulic functions, infiltration rate, and lysimeter size, and was furthermore affected by the degree of heterogeneity. In homogeneous soils with high saturated conductivities the devices perform poorly and even large lysimeters (width 250 cm) can be bypassed by the soil water. Heterogeneities of soil hydraulic properties result into a network of flow channels that enhance the sampling efficiency of the lysimeter plates. Solute breakthrough into zero-tension lysimeter occurs slightly retarded as compared to the free soil, but concentrations in the collected water are similar to the mean flux concentration in the undisturbed soil. To validate the results from the numerical study, a dual tracer study with seven lysimeters of 1.25×1.25 m area was conducted in the field. Three lysimeters were installed underneath a 1.2 m filling of contaminated silty sand, the others deeper in the undisturbed soil. The lysimeters directly underneath the filled soil material collected water with a collection efficiency of 45%. The deeper lysimeters did not collect any water. The arrival of the tracers showed that almost all collected water came from preferential flow paths.

The development of the bed bathymetry of an experimental dumping area was followed over three-and-a-half years by means of multibeam echosounder techniques. Two types of material were discharged in the bight of Mecklenburg in the Baltic Sea in approximately 20 m of water depth. One set of the discharges was 2900 m 3 of glacial till and the other set was a 2400 m 3 mixture of glacial till, sand and minor amounts of cohesive matter. Only approximately 2500 m 3 (86%) of the glacial till and 1500 m 3 (63%) of the mixed soil materials were deposited on the seabed. This means that already during the dumping process a considerable part of the sediment material drifted away. The glacial till formed crater-like rings of 30 m diameter with peaks up to 1.4 m above seabed, whereas the spatial structure of the mixed soil material was somewhat more diffuse, but with similar magnitudes in the peaks and troughs. The morphological changes were small and their quantification required a high measuring precision in the order of few cm in the vertical. The dominant processes of surface deformation was flattening of peaks and filling of troughs. The speed of this process decreased with horizontal scale: structures of less than 4 m horizontal extension had a trend to disappear within less than five years, whereas structures of larger than 8 m extension showed little change and are estimated to remain detectable for many decades. In contrast to the reworking of the matter inside the dumping structures, no net transport of material out of the dumping area could be detected. Extrapolating the observed morphological changes into the future it is estimated that without significant decrease in internal shear strength of the disposed till the structures will persist for at least 70 years. This can be attributed to the high internal stability of the dumped glacial till and the low hydrodynamic forces present at the seabed in this region.

Equivalent linear analyses are widely used for estimation of site response and safety status of rock-fill dams subjected to strong earthquakes. However, the average normalized curves incorporated in the equivalent-linear iterative process cannot precisely depict the variations of dynamic parameters with shearing strain for one type of soil material under a wide range of confining pressures. Thus, a modified approach for the determination of nonlinear properties for soil elements confined under a broad range of effective pressures in site response analyses for high rock-fill dams (>200 m) is proposed. In this approach, the normalized confining-pressure-interpolating curves (CPI curves) of each soil element under different effective stress are obtained by linearly interpolating or extrapolating by its in situ stress. By comparing the results obtained by equivalent linear analyses incorporating the average curves and the CPI curves, respectively, the impact of utilizing the recommended curves when determining nonlinear soil properties on site response analyses of high rock-fill dams (>200 m) is discussed. It is shown that the refinement in the determination of nonlinear properties during site response can be utilized in the near future by incorporating the results of this study in practice.

Hemispherical pan or dish-shaped trace fossils from the Cenozoic of the Central Patagonia are attributed to the burrowing action of cicadas. A new ichnotaxon, Feoich- nus challa igen. et isp. nov. is characterized by its hemispher- ical shape, mostly subvertical orientation, smoothed internal lining showing knobbly surface texture, and rough and irreg- ular external surface devoid of ornamentation. The wall is composed of a lining plus a layer of soil material consoli- dated passively by cicada excretions. In other specimens the wall shows a repetition of linings and soil layers reflecting changes in the position of the chambers. Grooves, which rep- resent traces of roots originally related to the feeding activi- ties of cicada nymphs, are located in the wall of many specimens of F. challa. These grooves are subvertical to sub- horizontal and show smooth surfaces with longitudinal stria- tions. The cicadan origin of these traces is supported by comparison of the fossils to modern cicada nymph chambers and by laboratory experiments. The most significant charac- ters that emerged from the comparison are the differential preservation of the basal part of the chambers, the interior lining with similar surface texture, and the presence of root traces in the wall and in the interior of the chamber. Addi- tional records of F. challa from the Cretaceous-Pliocene of the USA, the Oligocene of Ethiopia, and the Miocene of the United Arab Emirates and Kenya complete the current infor- mation yielded by the known body fossil record to help understand the evolutionary history of cicadas.

This review aims to give an overview of the potential hydrogeochemical information can have for landslide research and analyses the use of hydrogeochemical information to unravel the hydrological processes in landslide triggering. Landslides are well known for their data shortage; especially in case the hydrogeology is heterogeneous and difficult to measure. In this article we analyse the impact hydrogeochemical processes has on physical properties of the soil material and rock slopes, i.e. the relation with deformation rate and the relation of pore fluid composition and residual shear strength of soil material. Furthermore, the paper looks at the subsurface information that can be gained, i.e. the geological information of subsurface architecture and the hydrological information on origin of water, flow paths and travel times (using isotope analyses). Hydrochemical information used in both hard and soft rocks enables the display of clusters of water types, which is useful to identify contribution of different aquifers to the landslide area. Moreover, it can demonstrate the existence of lithologies and structures that are not visible with surface based geological investigations. Kinetic-based modelling is shown to be very useful in the interpretation of hydrogeochemical information. Lastly, it is shown that chemical information such as cation exchange properties coming from cored drilling is worthwhile for hydrological interpretations of landslides.

Micromorphology is the study of soil morphology over scales that range from the unaided eye to the submicroscopic. The essence of this field is that the soil material studied must be in an undisturbed state. Micromorphologists have developed a unique terminology and special techniques to identify and describe virtually any feature found in soils or weathered rock. Common features evaluated include macropores and soil structural aggregates, soil organisms including plant roots, and soil minerals in both the weathered and unweatered states. Micromorphology is used today to identify wetland soils, classify soils, and to evaluate how water and solutes move through soil. Presentation Information: Presentation Date: Monday, November 11, 2002 Presentation Time: 9:10 am

The Des-Bee-Dove Mine complex (owned by PacifiCorp and operated by Energy West Mining Company) had a long and rich mining history beginning in the 1880's. Since development of the mine surface facilities pre-dated SMCRA, initial construction did not include segregation and storage of soils. A total of approximately 13.8 hectares were disturbed prior to the commencement of reclamation in 1999. The goal of the reclamation project was to reclaim the mine site to within approximate original contour (AOC) using existing soil resources excavated on-site and achieve a diverse vegetative stand that would stabilize and protect the reclaimed slopes. Within this disturbed site, there were 14 portal openings necessitating elimination of approximately 762 meters of cut slopes. Also within this site was a 1.0 ha pad constructed into the side of steep canyon walls. This pad alone required approximately 36,000 m 3 to fill to AOC. With the cooperation of the Utah Division of Oil, Gas and Mining, a comprehensive soil management plan was developed. This plan assessed the quantity and quality of soils available for final reclamation throughout the mine site. The assessment involved excavating a series of trenches, placing them in strategic locations. These trenches were not only utilized to assess the quantity and quality of available substitute soil material, but also to ascertain the characteristics of the subsurface geology. Knowing this geology, approximate locations of natural drainages, rock faces, and drops were determined. By June 2003, approximately 215,000 m 3 of spoil and suitable soil were moved and placed to achieve the final reclaimed contour. Approximately 272 kg of native seed along with 3,500 bare root and containerized plants were manually planted. All work occurred on slopes with an approximate grade of 2 horizontal to 1 vertical. Today, three years after the completion of final reclamation, the Des-Bee-Dove Mine complex supports a broad vegetative cover that has protected and stabilized the reclaimed surface. Perennial grasses and woody plant species have begun to outnumber the exotic annuals. As desirable plant species progressively dominate the site, vegetative diversity increases significantly.

Heppia arenacea M. Schultz and Lempholemma polycarpum M. Schultz are described as new and placed in the Lichinaceae. Heppia arenacea occurs in soil-crust communities in southern Yemen and on Socotra. It colonizes both calcareous soil-crusts over limestone as well as soils originating from basaltic rocks. The sand-coloured, squamulose thallus, the erumpent, dark red apothecia and the incorporation of soil material into the thallus are diagnostic characters. Lempholemma polycarpum occurs on inclined limestone boulders in south-eastern Yemen. It is characterized by an umbilicate-lobate thallus with radiating, tongue-shaped, furcate lobes which bear numerous, small, immersed apothecia with punctiform discs.

This research describes the design and construction of an artificial rain simulator system and the results obtained with regards to suction-rainfall response of a cut slope in unsaturated residual soil of weathered sandstone of various weathering grades. From the field measurements, the shallow tensiometers are found to record an immediate initial increase in matric suction within the first 20 min of the simulated rain before a gradual drop in suction takes place. However no such initial spikes in suction readings were recorded by the deeper tensiometers. With constant rainfall for the next 130 min, a clear drop in soil suction was observed in all cases illustrating the effect of net infiltration process. Positive pore water pressure was even recorded by some of the deeper tensiometers. The suction recorded by the shallow tensiometers was always higher than those of the deeper tensiometers, indicating a reduction in suction with depth below the ground surface. In term of weathering grades, residual soil of weathered sandstone of weathering grade III has the highest infiltration rate indicating the more porous nature of this soil material. Like wise there is a steeper drop in suction during the rain at the said location.

Advanced numerical modes used for the description of performance of geosynthetic reinforced soil structures in terms of displacements corresponding to working loads well below collapse levels has created the need for material models for the geosynthetic and geosynthetic-soil interaction accounting for stiffness, yielding and strength properties. A direction dependent isotropic hardening, elastic-plastic-creep model for the geosynthetic, an elastic-perfectly plastic direction and normal stress dependent geosynthetic-soil interaction model, and a bounding surface plasticity model for soil material have been used in a finite element model of a geosynthetic pullout test. Predictions from the model have been compared to a series of pullout tests where it is seen that the model provides reasonable predictions of load-displacement pullout behavior. Systematic removal of material model components has shown that geosynthetic creep properties have a noticeable but minor impact on load-displacement predictions, while geosynthetic plasticity properties have a more significant role for load simulations where the material approaches rupture during pullout. Replacement of the bounding surface plasticity model for the soil material with a linear elastic model resulted in no significant differences in predictions.

The Bayesian probability model, using the weight-of-evidence method, was applied to the task of evaluating landslide susceptibility using GIS data. The location chosen for the study was the Janghung area in Korea, which suffered substantial landslide damage following heavy rain in 1998. Using the location of the landslides as well as topographic factors such as soil, forest and land use, the weight-of-evidence method was used to calculate each factor's rating. Tests of conditional independence were performed for the selection of the factors, allowing the large number of combinations of factors to be analyzed. For each factor rating, the contrast values, W+ and W–, were overlaid for landslide susceptibility mapping. The results of the analysis were verified using the observed landslide locations and, among the combinations, the slope, aspect, curvature, soil material and wood types show the best results.

The paper presents a comparative micromorphological analysis of the range of soil materials used to make the pottery of the hilly Galilee during the Roman period, and the ceramic products made from these materials. The four soil units that served as raw material for most of the pottery made in this period and region are examined along with pottery derived from each of them. For each soil unit, the soil characteristics and processes are described, followed by a presentation of the micromorphological characteristics of the soil material and those of the pottery made from that material. The contribution of the aeolian dust component to the soil materials is discussed as well as the identification of the tempering materials (nonplastics or other soil materials) added to the pottery paste. The study demonstrates the close correlation in microfabric between the pottery and original soil materials, sheds light on the raw material selection and modification practices of the potters of Roman Galilee, and has significant implications for provenance studies, using chemical analysis, on the pottery of this period and region. © 2002 Wiley Periodicals, Inc.

The paper presents proposals for the assessment of subsoil stiffness based on results of the seismic cone penetration test. Correlations between penetration parameters and constrained modulus were determined for three genetically different groups of cohesive soils. For the analyzed soil material quantitative estimation was also conducted for the parameter, which determines the relationship between the constrained modulus and initial shear modulus. A marked trend was shown for this parameter with the soil behavior type index used in the classification of soils in the cone penetration test.

Data about the background concentration of potentially toxic elements in soils are indispensable for establishing legislative limits, risk thresholds and, in general, assess the intensity of the pollution. Crude earth buildings are diffuse in the Mediterranean area and may be used as archives for original concentration of various metals. The building technique uses local soil which is mixed with water, let dry in formworks and covered with plaster. This has protected the soil material from external additions. The aim of this work was to evaluate the crude earth walls as repositories of the original concentration of some metals. Six crude earth walls were investigated in a location in northwestern Italy. Their concentration in Cd, Cu, Cr, Ni, Pb and Zn were measured and compared with those of surrounding soil profiles. Also, the results were compared with those of the Province. Organic carbon and pH seem to confirm the different evolution of the soils in the field with respect to that in the wall while iron oxides were not useful in discriminating the samples. Cadmium and Pb appeared to be the most reliable for the evaluation of the accumulated contamination evaluated while Cr and Ni are influenced by the lithogenic substratum.

This paper presents a method for evaluating sinkhole potential based on eleven sinkhole characteristics that may be found during a subsurface investigation. In brief, the characteristics address the density of soil material at different depths, drilling properties, stratigraphic conditions and ground water levels. Each of the eleven-sinkhole characteristics is discussed in detail so the investigator can identify each characteristic during the subsurface investigation. Once the total number of sinkhole characteristics are identified the Sinkhole Score for the site is determined. The Sinkhole Score is the number of sinkhole characteristics found compared to the number of sinkhole characteristics possible. Also discussed is the Weighted Sinkhole Score, which is a modification to the Sinkhole Score that accounts for the importance of each characteristic. The significance of the sinkhole scoring method is discussed in determining the likelihood that a sinkhole has impacted existing construction or could impact future site development. The paper also discusses other factors that can cause sinkhole-like distress and discusses methods of detection.